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The future of ultra-compact cameras

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April 18, 2005 8:16:30 AM

Archived from groups: rec.photo.digital (More info?)

After many days of surfing and researching until my eyes and neck
hurts, I've finally decided on the Sony SD200. What I'm looking for
was a digicam that I could take with me everyday like I would with my
cellphone. It's my first digicam. I'm just disappointed at what's out
there. A lot of them claim they're ultra-compact but in reality,
they're not something you can carry with you all the time. The SD200
is only 131g with battery and SD card. That's the smallest and
realistically portable camera I could find. The downside is, it's only
3.2 MP. Hey, if I want to take something that I could make a poster
with, I'd buy a different camera but what are the chances I'll have
that with me when I need it? So I figure, better with a 3.2 MP than
nothing at all. The SD300 was my next choice but the price difference
isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
Can't go wrong with either of them but their movie ability isn't as
good, the Exilims lack AF assist lamp.

I wonder when we'll start seeing ultra-cameras that are in the 7 MP
range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
capability like the Canon's, AF assist lamp, image stabilization and
continuous shots ability? All that for under $400? Do you guys think
we'll see that in the next 2 years?
Anonymous
April 18, 2005 11:36:30 AM

Archived from groups: rec.photo.digital (More info?)

Megapixels are just marketing hype. What matters is sensor size.
Sensor size is like the diameter of a pizza. Megapixels is like how
many pieces you slice up the pizza into. A 7 megapixel compact camera
with a 1/3" sensor is like a 15 cm mini-pizza cut into 200 little 1cm
slices. The pizza manufacturer then advertises "200 slices will
satisfy the biggest appetite!" while making you look deep in the
technical specs to find out the total amount of pizza in the box.

Bottom line: you will not make clean poster-sized prints with an
ultra-pocket camera no matter what you do. Professionals who make
poster-size prints use big cameras with 1" or larger sensors for a
reason. With a very small camera, look for the lowest number of
megapixels you can find, not the highest.
Anonymous
April 18, 2005 5:55:28 PM

Archived from groups: rec.photo.digital (More info?)

Newbie wrote:
> After many days of surfing and researching until my eyes and neck
> hurts, I've finally decided on the Sony SD200. What I'm looking for
> was a digicam that I could take with me everyday like I would with my
> cellphone. It's my first digicam. I'm just disappointed at what's out
> there. A lot of them claim they're ultra-compact but in reality,
> they're not something you can carry with you all the time. The SD200
> is only 131g with battery and SD card. That's the smallest and
> realistically portable camera I could find. The downside is, it's only
> 3.2 MP. Hey, if I want to take something that I could make a poster
> with, I'd buy a different camera but what are the chances I'll have
> that with me when I need it? So I figure, better with a 3.2 MP than
> nothing at all. The SD300 was my next choice but the price difference
> isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
> whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
> Can't go wrong with either of them but their movie ability isn't as
> good, the Exilims lack AF assist lamp.
>
> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
> capability like the Canon's, AF assist lamp, image stabilization and
> continuous shots ability? All that for under $400? Do you guys think
> we'll see that in the next 2 years?
>
Yes. Very likely. Look back two years at what was available, and
compare it with now.


--
Ron Hunter rphunter@charter.net
Related resources
Anonymous
April 18, 2005 5:58:38 PM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
> Megapixels are just marketing hype. What matters is sensor size.
> Sensor size is like the diameter of a pizza. Megapixels is like how
> many pieces you slice up the pizza into. A 7 megapixel compact camera
> with a 1/3" sensor is like a 15 cm mini-pizza cut into 200 little 1cm
> slices. The pizza manufacturer then advertises "200 slices will
> satisfy the biggest appetite!" while making you look deep in the
> technical specs to find out the total amount of pizza in the box.
>
> Bottom line: you will not make clean poster-sized prints with an
> ultra-pocket camera no matter what you do. Professionals who make
> poster-size prints use big cameras with 1" or larger sensors for a
> reason. With a very small camera, look for the lowest number of
> megapixels you can find, not the highest.

Silly idea, silly comparison.
So, if he can find a really small camera with only 1 pixel, that would
be best, especially if the sensor was 2 inches on a side? Sigh.
While a larger sensor is currently 'better', in a technical sense, that
doesn't mean tomorrow's sensors won't be even better at the smaller size
than today's larger ones.


--
Ron Hunter rphunter@charter.net
Anonymous
April 18, 2005 5:58:39 PM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter <rphunter@charter.net> writes:
> > reason. With a very small camera, look for the lowest number of
> > megapixels you can find, not the highest.
>
> Silly idea, silly comparison.
> So, if he can find a really small camera with only 1 pixel, that would
> be best, especially if the sensor was 2 inches on a side? Sigh.
> While a larger sensor is currently 'better', in a technical sense,
> that doesn't mean tomorrow's sensors won't be even better at the
> smaller size than today's larger ones.

I don't think you can find a 1 pixel camera. But if there's a 1MP
digicam available then that's the one to buy. The SD200 is preferable
to the SD300, etc. If I could buy a D70 with a 1MP sensor and 6x the
usable ISO of the current D70, I would probably buy one. The 2.7MP
Nikon D1H still makes better large prints than any umpteen-megapixel
compact digicam, because of its large sensor area per pixel. The D70
does even better at low ISO than the D1H, but any sensor area per
pixel less than the D70's seems to result in worse enlargements, not
better (e.g. Canon 20d). Even the EOS-1DS mk II (24x36 sensor, 16MP)
is likely pushing it. There's careful optimization problems involved.
It's not just a matter of slicing the sensor into as many pixels as
one possibly can, as is done in small consumer cameras.
April 18, 2005 7:17:14 PM

Archived from groups: rec.photo.digital (More info?)

"Newbie" <chromallly@yahoo.com> wrote:

>After many days of surfing and researching until my eyes and neck
>hurts, I've finally decided on the Sony SD200.

??? I couldn't find that model, got a link? I'm thinking you ment a
canon. Sony does make a lot of pocket cameras.

I'd like to add steady shot to the movie mode wish list.

Wes


--
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Whiskey Echo Sierra Sierra AT Alpha Charlie Echo Golf Romeo Oscar Paul dot Charlie Charlie
Lycos address is a spam trap.
Anonymous
April 18, 2005 7:29:45 PM

Archived from groups: rec.photo.digital (More info?)

Nope, even if it was possible they wouldn't realize it.I say it again, if
you *really* want movies, get a good camcorder.IMHO cameras are for taking
pictures, and camcorders are specialized in taking movies (I have the Kodak
CX 7300 and sony ccd-tr425e

--
Tzortzakakis Dimitrios
major in electrical engineering, freelance electrician
FH von Iraklion-Kreta, freiberuflicher Elektriker
dimtzort AT otenet DOT gr
? "Newbie" <chromallly@yahoo.com> ?????? ??? ??????
news:1113822990.199057.92160@l41g2000cwc.googlegroups.com...
> After many days of surfing and researching until my eyes and neck
> hurts, I've finally decided on the Sony SD200. What I'm looking for
> was a digicam that I could take with me everyday like I would with my
> cellphone. It's my first digicam. I'm just disappointed at what's out
> there. A lot of them claim they're ultra-compact but in reality,
> they're not something you can carry with you all the time. The SD200
> is only 131g with battery and SD card. That's the smallest and
> realistically portable camera I could find. The downside is, it's only
> 3.2 MP. Hey, if I want to take something that I could make a poster
> with, I'd buy a different camera but what are the chances I'll have
> that with me when I need it? So I figure, better with a 3.2 MP than
> nothing at all. The SD300 was my next choice but the price difference
> isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
> whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
> Can't go wrong with either of them but their movie ability isn't as
> good, the Exilims lack AF assist lamp.
>
> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
> capability like the Canon's, AF assist lamp, image stabilization and
> continuous shots ability? All that for under $400? Do you guys think
> we'll see that in the next 2 years?
>
Anonymous
April 18, 2005 7:29:46 PM

Archived from groups: rec.photo.digital (More info?)

Dimitrios Tzortzakakis wrote:
> Nope, even if it was possible they wouldn't realize it.I say it again, if
> you *really* want movies, get a good camcorder.IMHO cameras are for taking
> pictures, and camcorders are specialized in taking movies (I have the Kodak
> CX 7300 and sony ccd-tr425e
>
> --
> Tzortzakakis Dimitrios
> major in electrical engineering, freelance electrician
> FH von Iraklion-Kreta, freiberuflicher Elektriker
> dimtzort AT otenet DOT gr
> ? "Newbie" <chromallly@yahoo.com> ?????? ??? ??????
> news:1113822990.199057.92160@l41g2000cwc.googlegroups.com...
>
>>After many days of surfing and researching until my eyes and neck
>>hurts, I've finally decided on the Sony SD200. What I'm looking for
>>was a digicam that I could take with me everyday like I would with my
>>cellphone. It's my first digicam. I'm just disappointed at what's out
>>there. A lot of them claim they're ultra-compact but in reality,
>>they're not something you can carry with you all the time. The SD200
>>is only 131g with battery and SD card. That's the smallest and
>>realistically portable camera I could find. The downside is, it's only
>>3.2 MP. Hey, if I want to take something that I could make a poster
>>with, I'd buy a different camera but what are the chances I'll have
>>that with me when I need it? So I figure, better with a 3.2 MP than
>>nothing at all. The SD300 was my next choice but the price difference
>>isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
>>whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
>>Can't go wrong with either of them but their movie ability isn't as
>>good, the Exilims lack AF assist lamp.
>>
>>I wonder when we'll start seeing ultra-cameras that are in the 7 MP
>>range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
>>capability like the Canon's, AF assist lamp, image stabilization and
>>continuous shots ability? All that for under $400? Do you guys think
>>we'll see that in the next 2 years?
>>
>
>
>
I didn't see any mention of video in his post..


--
Ron Hunter rphunter@charter.net
Anonymous
April 18, 2005 7:51:47 PM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
> Ron Hunter <rphunter@charter.net> writes:
>
>>>reason. With a very small camera, look for the lowest number of
>>>megapixels you can find, not the highest.
>>
>>Silly idea, silly comparison.
>>So, if he can find a really small camera with only 1 pixel, that would
>>be best, especially if the sensor was 2 inches on a side? Sigh.
>>While a larger sensor is currently 'better', in a technical sense,
>>that doesn't mean tomorrow's sensors won't be even better at the
>>smaller size than today's larger ones.
>
>
> I don't think you can find a 1 pixel camera. But if there's a 1MP
> digicam available then that's the one to buy. The SD200 is preferable
> to the SD300, etc. If I could buy a D70 with a 1MP sensor and 6x the
> usable ISO of the current D70, I would probably buy one. The 2.7MP
> Nikon D1H still makes better large prints than any umpteen-megapixel
> compact digicam, because of its large sensor area per pixel. The D70
> does even better at low ISO than the D1H, but any sensor area per
> pixel less than the D70's seems to result in worse enlargements, not
> better (e.g. Canon 20d). Even the EOS-1DS mk II (24x36 sensor, 16MP)
> is likely pushing it. There's careful optimization problems involved.
> It's not just a matter of slicing the sensor into as many pixels as
> one possibly can, as is done in small consumer cameras.

Lots of interacting aspects. Lens size, and quality, sensor size and
number of pixels, quality of the electronics and firmware in the camera.
All bear on the final product. Go too cheap on any of them, and
picture quality suffers. But, with improvements in technology, things
will get better.
n

--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 12:33:19 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter wrote:
> Paul Rubin wrote:
>
>> Megapixels are just marketing hype. What matters is sensor size.
>> Sensor size is like the diameter of a pizza. Megapixels is like how
>> many pieces you slice up the pizza into. A 7 megapixel compact camera
>> with a 1/3" sensor is like a 15 cm mini-pizza cut into 200 little 1cm
>> slices. The pizza manufacturer then advertises "200 slices will
>> satisfy the biggest appetite!" while making you look deep in the
>> technical specs to find out the total amount of pizza in the box.
>>
>> Bottom line: you will not make clean poster-sized prints with an
>> ultra-pocket camera no matter what you do. Professionals who make
>> poster-size prints use big cameras with 1" or larger sensors for a
>> reason. With a very small camera, look for the lowest number of
>> megapixels you can find, not the highest.
>
>
> Silly idea, silly comparison.
> So, if he can find a really small camera with only 1 pixel, that would
> be best, especially if the sensor was 2 inches on a side? Sigh.

There is a lot of truth in what Paul says.

> While a larger sensor is currently 'better', in a technical sense, that
> doesn't mean tomorrow's sensors won't be even better at the smaller size
> than today's larger ones.

Current quality cameras are photon noise limited. This is shown
at: Digital Cameras: Does Pixel Size Matter?
Factors in Choosing a Digital Camera
http://www.clarkvision.com/imagedetail/does.pixel.size....

Small pixels simply can't gather the number of photons of a large
sensor, even if the quantum efficiency were 100%. The way
ISO, is specified, along with f/ratio, fixes the number of
photons per square mm on the sensor area. That won't change
(e.g. in this millennium) as there are a finite number of photons
put out by the sun. Large sensor cameras, like the Canon 1D Mark II
(8.2 micron pixels) collect a maximum of about 52,000 electrons
(proportional to photons) in one pixel. The signal-to-noise
maximum for that camera is square root 52,000 = 228. It's
downhill from there with smaller sensors (see the above web page).

Roger
Anonymous
April 19, 2005 12:34:31 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter wrote:

> Newbie wrote:
>
>> After many days of surfing and researching until my eyes and neck
>> hurts, I've finally decided on the Sony SD200. What I'm looking for
>> was a digicam that I could take with me everyday like I would with my
>> cellphone. It's my first digicam. I'm just disappointed at what's out
>> there. A lot of them claim they're ultra-compact but in reality,
>> they're not something you can carry with you all the time. The SD200
>> is only 131g with battery and SD card. That's the smallest and
>> realistically portable camera I could find. The downside is, it's only
>> 3.2 MP. Hey, if I want to take something that I could make a poster
>> with, I'd buy a different camera but what are the chances I'll have
>> that with me when I need it? So I figure, better with a 3.2 MP than
>> nothing at all. The SD300 was my next choice but the price difference
>> isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
>> whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
>> Can't go wrong with either of them but their movie ability isn't as
>> good, the Exilims lack AF assist lamp.
>>
>> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
>> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
>> capability like the Canon's, AF assist lamp, image stabilization and
>> continuous shots ability? All that for under $400? Do you guys think
>> we'll see that in the next 2 years?
>>
> Yes. Very likely. Look back two years at what was available, and
> compare it with now.
>
>
No. The physical limit is here: the photon noise limit.
There is room for a small improvement if quantum efficiency can
be increased.

Roger
Anonymous
April 19, 2005 12:52:50 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter <rphunter@charter.net> writes:
> Lots of interacting aspects. Lens size, and quality, sensor size and
> number of pixels, quality of the electronics and firmware in the
> camera. All bear on the final product. Go too cheap on any of them,
> and picture quality suffers. But, with improvements in technology,
> things will get better.

But as things get better through technology, the meaning of "ultra
compact" will change. Instead of meaning a camera the size of a
cigarette pack, it will mean a camera the size of a cigarette lighter.
That means a 1/8" CCD instead of 1/3" etc., and all the while the
manufacturers will be advertising more and more megapixels and newbies
will keep expecting to make poster size prints with the things. And
when the lighter-size cameras are capable of such, ultra-compact will
come to mean a camera built into a shirt button. It never stops.
April 19, 2005 2:15:06 AM

Archived from groups: rec.photo.digital (More info?)

Newbie wrote:
> After many days of surfing and researching until my eyes and neck
> hurts, I've finally decided on the Sony SD200.

A little correction here, I meant Canon SD200. My eyes and neck still
hurts when I wrote my original thread :) 

I'm not expecting the ultra-compact to be the end-all answer to the
future of cameras. I just want them to do decent 8X10 pictures,
portable, take sharp pictures, good colors, good optical zoom, and take
pictures at low light. The Panasonic Lumix FX7 almost fit the bill. 5
MP, AF assist lamp, image stabilizer, 3x optical zoom. If they could
just shed 1 cu inch overall, shed 10g of weight, with the picture
quality of Canon SD series, that might be good enough. They can start
by shrinking the LCD down from 2.5" to 2". That should solve the
weight and dimension problem.

There are many many instances where I wish I had a camera with me.
When I'm walking, I'd see something amusing and wish I could preserve
it. Maybe a pigeon getting his head stuck on a bottle. With the
SD200, I wouldn't be caught empty handed anymore. On vacations and
events, I'd bring a different camera. I hope you guys get what I'm
trying to say here.
Anonymous
April 19, 2005 2:52:22 AM

Archived from groups: rec.photo.digital (More info?)

Newbie wrote:
> ...finally decided on the Sony SD200. What I'm looking for
> was a digicam that I could take with me everyday like I would
> with my cellphone....The SD200... is only 131g with battery and
> SD card....it's only 3.2 MP....SD300 was my next choice...The
> Exilim Z50, Lumix FX7 was my other 2 choices.
> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
> capability like the Canon's, AF assist lamp, image stabilization and
> continuous shots ability? All that for under $400? Do you guys
> think we'll see that in the next 2 years?



Nobody knows the answer and the manufacturers keep mum of course. If you
can't wait that long to find out, look at these models here. They do not
meet your requirement exactly but close.

Ricoh Caplio R1v (i.e. Rollei dr5 in Americas) or R2
or GX is even more interesting
Casio Exilim Pro EX-P505
or EX-Z750

One major deciding criterion in my choice of a carry-everywhere pocket-able
camera is the fun factor in using the machine. There are many ultra compact
or compact cameras that provide automatic configuration for different
settings and perform well (no, not "poster" sized), but few that also
provide a full range -- not a frustratingly half-hearted attempt (the
manufacturers' to safeguard the high end market) -- of user's customizable
adjustment to the configurations. To me, this latter is what doing
photography is about, which is missing in the all too familiar automatic,
preset point-and-shoot snap shooters.

--
Lin Chung.
[The Water Margins of Liang Shan Po were at the time of the Sung dynasty.
Replace that with "ntlworld" for emails.]
Anonymous
April 19, 2005 5:49:03 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:
> Ron Hunter wrote:
>
>> Paul Rubin wrote:
>>
>>> Megapixels are just marketing hype. What matters is sensor size.
>>> Sensor size is like the diameter of a pizza. Megapixels is like how
>>> many pieces you slice up the pizza into. A 7 megapixel compact camera
>>> with a 1/3" sensor is like a 15 cm mini-pizza cut into 200 little 1cm
>>> slices. The pizza manufacturer then advertises "200 slices will
>>> satisfy the biggest appetite!" while making you look deep in the
>>> technical specs to find out the total amount of pizza in the box.
>>>
>>> Bottom line: you will not make clean poster-sized prints with an
>>> ultra-pocket camera no matter what you do. Professionals who make
>>> poster-size prints use big cameras with 1" or larger sensors for a
>>> reason. With a very small camera, look for the lowest number of
>>> megapixels you can find, not the highest.
>>
>>
>>
>> Silly idea, silly comparison.
>> So, if he can find a really small camera with only 1 pixel, that would
>> be best, especially if the sensor was 2 inches on a side? Sigh.
>
>
> There is a lot of truth in what Paul says.
>
>> While a larger sensor is currently 'better', in a technical sense,
>> that doesn't mean tomorrow's sensors won't be even better at the
>> smaller size than today's larger ones.
>
>
> Current quality cameras are photon noise limited. This is shown
> at: Digital Cameras: Does Pixel Size Matter?
> Factors in Choosing a Digital Camera
> http://www.clarkvision.com/imagedetail/does.pixel.size....
>
> Small pixels simply can't gather the number of photons of a large
> sensor, even if the quantum efficiency were 100%. The way
> ISO, is specified, along with f/ratio, fixes the number of
> photons per square mm on the sensor area. That won't change
> (e.g. in this millennium) as there are a finite number of photons
> put out by the sun. Large sensor cameras, like the Canon 1D Mark II
> (8.2 micron pixels) collect a maximum of about 52,000 electrons
> (proportional to photons) in one pixel. The signal-to-noise
> maximum for that camera is square root 52,000 = 228. It's
> downhill from there with smaller sensors (see the above web page).
>
> Roger
I will take a 228:1 S/N ratio ANY DAY. Imagine if you could get that in
a stereo! What will improve is the lens, to get more photons focused on
the sensor, and the processing of the output from the sensor. Example.
Many DSLR cameras run a 'picture' from the covered sensor into memory,
and then when the sensor is exposed to the image, combine the prescan
with the image to eliminate noise. The results are quite significantly
improved. I am sure other methods of making the most of that S/N ratio
will be developed as signal processors become more sophisticated, and
the processing power of the internal electronics improves.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 5:49:04 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter <rphunter@charter.net> writes:
> > put out by the sun. Large sensor cameras, like the Canon 1D Mark II
> > (8.2 micron pixels) collect a maximum of about 52,000 electrons
> > (proportional to photons) in one pixel. The signal-to-noise
> > maximum for that camera is square root 52,000 = 228. It's
> > downhill from there with smaller sensors (see the above web page).
> > Roger
> I will take a 228:1 S/N ratio ANY DAY. Imagine if you could get that
> in a stereo!

In Zone System terms, that says even in the 1D Mark II, Zone 8 is
swamped by noise. You lose a couple more zones with an ultracompact.

> What will improve is the lens, to get more photons focused on the
> sensor, and the processing of the output from the sensor.
> Example. Many DSLR cameras run a 'picture' from the covered sensor
> into memory, and then when the sensor is exposed to the image,
> combine the prescan with the image to eliminate noise.

No that only gets rid of hot pixels. Noise is random and unpredictable.

> The results are quite significantly improved. I am sure other
> methods of making the most of that S/N ratio will be developed as
> signal processors become more sophisticated, and the processing
> power of the internal electronics improves.

There are physical limits that are as inescapeable as the speed of light.
That's what Roger was referring to.
Anonymous
April 19, 2005 5:50:54 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:
> Ron Hunter wrote:
>
>> Newbie wrote:
>>
>>> After many days of surfing and researching until my eyes and neck
>>> hurts, I've finally decided on the Sony SD200. What I'm looking for
>>> was a digicam that I could take with me everyday like I would with my
>>> cellphone. It's my first digicam. I'm just disappointed at what's out
>>> there. A lot of them claim they're ultra-compact but in reality,
>>> they're not something you can carry with you all the time. The SD200
>>> is only 131g with battery and SD card. That's the smallest and
>>> realistically portable camera I could find. The downside is, it's only
>>> 3.2 MP. Hey, if I want to take something that I could make a poster
>>> with, I'd buy a different camera but what are the chances I'll have
>>> that with me when I need it? So I figure, better with a 3.2 MP than
>>> nothing at all. The SD300 was my next choice but the price difference
>>> isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
>>> whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
>>> Can't go wrong with either of them but their movie ability isn't as
>>> good, the Exilims lack AF assist lamp.
>>>
>>> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
>>> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
>>> capability like the Canon's, AF assist lamp, image stabilization and
>>> continuous shots ability? All that for under $400? Do you guys think
>>> we'll see that in the next 2 years?
>>>
>> Yes. Very likely. Look back two years at what was available, and
>> compare it with now.
>>
>>
> No. The physical limit is here: the photon noise limit.
> There is room for a small improvement if quantum efficiency can
> be increased.
>
> Roger
I recall reading similar sentiments from experts in the field back when
they were saying 450 baud was the fastest modems would ever go... I
suspect the results will be similar to later results in that realm.
Technology has way of finding a way.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 5:53:06 AM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
> Ron Hunter <rphunter@charter.net> writes:
>
>>Lots of interacting aspects. Lens size, and quality, sensor size and
>>number of pixels, quality of the electronics and firmware in the
>>camera. All bear on the final product. Go too cheap on any of them,
>>and picture quality suffers. But, with improvements in technology,
>>things will get better.
>
>
> But as things get better through technology, the meaning of "ultra
> compact" will change. Instead of meaning a camera the size of a
> cigarette pack, it will mean a camera the size of a cigarette lighter.
> That means a 1/8" CCD instead of 1/3" etc., and all the while the
> manufacturers will be advertising more and more megapixels and newbies
> will keep expecting to make poster size prints with the things. And
> when the lighter-size cameras are capable of such, ultra-compact will
> come to mean a camera built into a shirt button. It never stops.

One thing will probably not change much, and that is the size prints
people will expect to get from their cameras. Not many users expect, or
want, a 20x30 of every picture, or ANY picture, for that matter. For
the vast majority, 4x6 is the largest print they will ever make. Some,
like me, won't print a significant number of their pictures at all.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 5:53:07 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter <rphunter@charter.net> writes:
> One thing will probably not change much, and that is the size prints
> people will expect to get from their cameras. Not many users expect,
> or want, a 20x30 of every picture, or ANY picture, for that matter.
> For the vast majority, 4x6 is the largest print they will ever make.
> Some, like me, won't print a significant number of their pictures at
> all.

I've seen 12x18 prints made from 320x240 pixel images. The prints
looked pretty soft from up close, but from a distance (which is how
you'd normally view such a print) they were way better than one might
expect.
Anonymous
April 19, 2005 5:55:16 AM

Archived from groups: rec.photo.digital (More info?)

Newbie wrote:
> Newbie wrote:
>
>>After many days of surfing and researching until my eyes and neck
>>hurts, I've finally decided on the Sony SD200.
>
>
> A little correction here, I meant Canon SD200. My eyes and neck still
> hurts when I wrote my original thread :) 
>
> I'm not expecting the ultra-compact to be the end-all answer to the
> future of cameras. I just want them to do decent 8X10 pictures,
> portable, take sharp pictures, good colors, good optical zoom, and take
> pictures at low light. The Panasonic Lumix FX7 almost fit the bill. 5
> MP, AF assist lamp, image stabilizer, 3x optical zoom. If they could
> just shed 1 cu inch overall, shed 10g of weight, with the picture
> quality of Canon SD series, that might be good enough. They can start
> by shrinking the LCD down from 2.5" to 2". That should solve the
> weight and dimension problem.
>
> There are many many instances where I wish I had a camera with me.
> When I'm walking, I'd see something amusing and wish I could preserve
> it. Maybe a pigeon getting his head stuck on a bottle. With the
> SD200, I wouldn't be caught empty handed anymore. On vacations and
> events, I'd bring a different camera. I hope you guys get what I'm
> trying to say here.
>
Vacations is when I want a small, light camera. Photography is
incidental to me on vacation, not the purpose.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 3:04:53 PM

Archived from groups: rec.photo.digital (More info?)

In article <1113822990.199057.92160@l41g2000cwc.googlegroups.com>,
"Newbie" <chromallly@yahoo.com> wrote:

> After many days of surfing and researching until my eyes and neck
> hurts, I've finally decided on the Sony SD200. What I'm looking for
> was a digicam that I could take with me everyday like I would with my
> cellphone. It's my first digicam. I'm just disappointed at what's out
> there. A lot of them claim they're ultra-compact but in reality,
> they're not something you can carry with you all the time. The SD200
> is only 131g with battery and SD card. That's the smallest and
> realistically portable camera I could find. The downside is, it's only
> 3.2 MP. Hey, if I want to take something that I could make a poster
> with, I'd buy a different camera but what are the chances I'll have
> that with me when I need it? So I figure, better with a 3.2 MP than
> nothing at all. The SD300 was my next choice but the price difference
> isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
> whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
> Can't go wrong with either of them but their movie ability isn't as
> good, the Exilims lack AF assist lamp.
>
> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
> capability like the Canon's, AF assist lamp, image stabilization and
> continuous shots ability? All that for under $400? Do you guys think
> we'll see that in the next 2 years?

IMO You're considering a single 'perfect' camera that will satisfy all
your needs. At present I'm using two - a Fuji S7000 and Fuji F440 and am
considering a third - the Panasonic FZ5. All these cameras were bought
for different reasons - the S7000 because it seemed a logical
replacement for my first digital (Sony S-70) while the F440 was bought
as a 'carry everywhere' camera - the Panasonic has image stabilization
and a 12x zoom - useful in many situations - it's only 5 megapixels
compared to the 6.3 (12.6 interpolated) of the S7000 but the other
advantages compensate for this apparent 'lack'.

If you wait for the ideal camera to come along, you'll wait forever and
lose the advantages of digital photography.

Choose a camera 'here and now' that satisfies most of your needs while
considering another 'wants list' for future purchases.
Anonymous
April 19, 2005 3:04:54 PM

Archived from groups: rec.photo.digital (More info?)

Stewy wrote:
> In article <1113822990.199057.92160@l41g2000cwc.googlegroups.com>,
> "Newbie" <chromallly@yahoo.com> wrote:
>
>
>>After many days of surfing and researching until my eyes and neck
>>hurts, I've finally decided on the Sony SD200. What I'm looking for
>>was a digicam that I could take with me everyday like I would with my
>>cellphone. It's my first digicam. I'm just disappointed at what's out
>>there. A lot of them claim they're ultra-compact but in reality,
>>they're not something you can carry with you all the time. The SD200
>>is only 131g with battery and SD card. That's the smallest and
>>realistically portable camera I could find. The downside is, it's only
>>3.2 MP. Hey, if I want to take something that I could make a poster
>>with, I'd buy a different camera but what are the chances I'll have
>>that with me when I need it? So I figure, better with a 3.2 MP than
>>nothing at all. The SD300 was my next choice but the price difference
>>isn't worth the extra 1 MP and the extra 15g weight. The SD500 is a
>>whopping 185g. The Exilim Z50, Lumix FX7 was my other 2 choices.
>>Can't go wrong with either of them but their movie ability isn't as
>>good, the Exilims lack AF assist lamp.
>>
>>I wonder when we'll start seeing ultra-cameras that are in the 7 MP
>>range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
>>capability like the Canon's, AF assist lamp, image stabilization and
>>continuous shots ability? All that for under $400? Do you guys think
>>we'll see that in the next 2 years?
>
>
> IMO You're considering a single 'perfect' camera that will satisfy all
> your needs. At present I'm using two - a Fuji S7000 and Fuji F440 and am
> considering a third - the Panasonic FZ5. All these cameras were bought
> for different reasons - the S7000 because it seemed a logical
> replacement for my first digital (Sony S-70) while the F440 was bought
> as a 'carry everywhere' camera - the Panasonic has image stabilization
> and a 12x zoom - useful in many situations - it's only 5 megapixels
> compared to the 6.3 (12.6 interpolated) of the S7000 but the other
> advantages compensate for this apparent 'lack'.
>
> If you wait for the ideal camera to come along, you'll wait forever and
> lose the advantages of digital photography.
>
> Choose a camera 'here and now' that satisfies most of your needs while
> considering another 'wants list' for future purchases.

I have the, for me, almost perfect camera. It does almost everything I
want. If it had IS, and a 10X optical zoom, then it would be perfect,
but ONLY if these features could be added without increasing its size,
or weight. Sometimes physical limitations are difficult to overcome.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 3:39:26 PM

Archived from groups: rec.photo.digital (More info?)

"Newbie" <chromallly@yahoo.com> writes:
> The A400 is huge. It's 165g without even factoring the memory card and
> batteries. I can't imagine carrying that with me everyday.

Oh, get a life. How much does your cellular phone weigh? How much do
your clothes weigh? If you want a tiny camera, try a Sony DSC-U20,
which can still make pretty good prints (2MP is enough for that--don't
believe the marketing hype for more pixels). If you just want
snapshots, try a cellphone camera.
Anonymous
April 19, 2005 7:39:12 PM

Archived from groups: rec.photo.digital (More info?)

Newbie wrote:
>>OK. This is another candidate:
>>http://www.digicamreview.co.uk/canon_powershot_a400_rev...
>
>
> The A400 is huge. It's 165g without even factoring the memory card and
> batteries. I can't imagine carrying that with me everyday.
>
With lithium battery, that would be about 8 oz. You could carry that in
your shirt pocket and forget it was there.
If you are worried about the weight of a flash card, you are way beyond
reason.


--
Ron Hunter rphunter@charter.net
Anonymous
April 19, 2005 8:36:55 PM

Archived from groups: rec.photo.digital (More info?)

Lin Chung wrote:
> Newbie wrote:
>> ...finally decided on the Sony SD200. What I'm looking for
>> was a digicam that I could take with me everyday like I would
>> with my cellphone....The SD200... is only 131g with battery and
>> SD card....it's only 3.2 MP....SD300 was my next choice...The
>> Exilim Z50, Lumix FX7 was my other 2 choices.
>> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
>> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
>> capability like the Canon's, AF assist lamp, image stabilization and
>> continuous shots ability? All that for under $400? Do you guys
>> think we'll see that in the next 2 years?
> Ricoh Caplio R1v (i.e. Rollei dr5 in Americas) or R2
> or GX is even more interesting
> Casio Exilim Pro EX-P505
> ...but few that also provide a full range...of user's customizable
> adjustment to the configurations....


OK. This is another candidate:
http://www.digicamreview.co.uk/canon_powershot_a400_rev...

I have none of these cameras, and, like you, I am still searching for my
first credible carried-everywhere pocketable 'PPA' (Personal Photographic
Assistant), Swiss army photographic 'knife'.

--
Lin Chung.
[The Water Margins of Liang Shan Po were at the time of the Sung dynasty.
Replace that with "ntlworld" for emails.]
April 19, 2005 10:07:00 PM

Archived from groups: rec.photo.digital (More info?)

> Oh, get a life. How much does your cellular phone weigh? How much
do
> your clothes weigh? If you want a tiny camera, try a Sony DSC-U20,
> which can still make pretty good prints (2MP is enough for
that--don't
> believe the marketing hype for more pixels). If you just want
> snapshots, try a cellphone camera.

My cellphone weighs 80g. There are already a lot of ultra-compact that
weighs less than the A400. The Z50, Z55, Z57, SD200, SD300, SD500,
FX7, Verve.... etc. etc. The SD200 that I got weighs 115g.

It's really up to the individual. If the A400 suits your needs, then
get one.
Anonymous
April 20, 2005 12:57:44 AM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
> Ron Hunter <rphunter@charter.net> writes:
>
>>>put out by the sun. Large sensor cameras, like the Canon 1D Mark II
>>>(8.2 micron pixels) collect a maximum of about 52,000 electrons
>>>(proportional to photons) in one pixel. The signal-to-noise
>>>maximum for that camera is square root 52,000 = 228. It's
>>>downhill from there with smaller sensors (see the above web page).
>>>Roger
>>
>>I will take a 228:1 S/N ratio ANY DAY. Imagine if you could get that
>>in a stereo!
>
>
> In Zone System terms, that says even in the 1D Mark II, Zone 8 is
> swamped by noise. You lose a couple more zones with an ultracompact.

In the case of electronic sensors, the signal-to-noise is the
square root of the number of electrons collected. So in the case of
DSLRs like the 1DII, 10 stops down from full well, you get 50 electrons,
with Poisson noise of 7 electrons, and at ISO 100, the read noise is
about 8 electrons, so the signal-to-noise is still about
50/sqr(8^2+7^2) = 5. This is much better than any film. See:
http://clarkvision.com/imagedetail/digital.signal.to.no...

>>What will improve is the lens, to get more photons focused on the
>>sensor, and the processing of the output from the sensor.
>>Example. Many DSLR cameras run a 'picture' from the covered sensor
>>into memory, and then when the sensor is exposed to the image,
>>combine the prescan with the image to eliminate noise.
>
>
> No that only gets rid of hot pixels. Noise is random and unpredictable.

Ron,
At a given f/stop, like f/4 you get the same number of photons
per square mm. No lens improvements will improve that.
Faster lenses are not the universal answer, as sometimes we
want depth of field.

>>The results are quite significantly improved. I am sure other
>>methods of making the most of that S/N ratio will be developed as
>>signal processors become more sophisticated, and the processing
>>power of the internal electronics improves.
>
>
> There are physical limits that are as inescapeable as the speed of light.
> That's what Roger was referring to.

Yes, that was what I was referring to. Quantum efficiency can be improved,
but for a long time we haven't seen it. But assuming improvements
there, we could see a perhaps factor of 2 improvement. That still
won't make the small sensors as good as current DSLRs.

Roger
Anonymous
April 20, 2005 1:05:53 AM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter wrote:

> Roger N. Clark (change username to rnclark) wrote:
>
>> Ron Hunter wrote:
>>
>>>
>>> Yes. Very likely. Look back two years at what was available, and
>>> compare it with now.
>>>
>>>
>> No. The physical limit is here: the photon noise limit.
>> There is room for a small improvement if quantum efficiency can
>> be increased.
>>
>> Roger
>
> I recall reading similar sentiments from experts in the field back when
> they were saying 450 baud was the fastest modems would ever go... I
> suspect the results will be similar to later results in that realm.
> Technology has way of finding a way.

Ron,
the 450 baud thing was not a physical limit. This is not the same
thing. Until someone rewrites the laws of physics, we have
physical limits. Photon counting statistics is one of them.
It says that the knowledge of the correct signal level has an
error of the square root of the number of photons counted.
That error appears as noise in digital camera images.
Modern high quality digital cameras (whether DSLRs or
small P&S) are photon noise limited.
see:
http://www.clarkvision.com/imagedetail/does.pixel.size....
http://clarkvision.com/imagedetail/digital.signal.to.no...

Roger
Anonymous
April 20, 2005 7:03:18 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:
> Paul Rubin wrote:
>
>> Ron Hunter <rphunter@charter.net> writes:
>>
>>>> put out by the sun. Large sensor cameras, like the Canon 1D Mark II
>>>> (8.2 micron pixels) collect a maximum of about 52,000 electrons
>>>> (proportional to photons) in one pixel. The signal-to-noise
>>>> maximum for that camera is square root 52,000 = 228. It's
>>>> downhill from there with smaller sensors (see the above web page).
>>>> Roger
>>>
>>>
>>> I will take a 228:1 S/N ratio ANY DAY. Imagine if you could get that
>>> in a stereo!
>>
>>
>>
>> In Zone System terms, that says even in the 1D Mark II, Zone 8 is
>> swamped by noise. You lose a couple more zones with an ultracompact.
>
>
> In the case of electronic sensors, the signal-to-noise is the
> square root of the number of electrons collected. So in the case of
> DSLRs like the 1DII, 10 stops down from full well, you get 50 electrons,
> with Poisson noise of 7 electrons, and at ISO 100, the read noise is
> about 8 electrons, so the signal-to-noise is still about
> 50/sqr(8^2+7^2) = 5. This is much better than any film. See:
> http://clarkvision.com/imagedetail/digital.signal.to.no...
>
>>> What will improve is the lens, to get more photons focused on the
>>> sensor, and the processing of the output from the sensor.
>>> Example. Many DSLR cameras run a 'picture' from the covered sensor
>>> into memory, and then when the sensor is exposed to the image,
>>> combine the prescan with the image to eliminate noise.
>>
>>
>>
>> No that only gets rid of hot pixels. Noise is random and unpredictable.
>
>
> Ron,
> At a given f/stop, like f/4 you get the same number of photons
> per square mm. No lens improvements will improve that.
> Faster lenses are not the universal answer, as sometimes we
> want depth of field.
>
>>> The results are quite significantly improved. I am sure other
>>> methods of making the most of that S/N ratio will be developed as
>>> signal processors become more sophisticated, and the processing
>>> power of the internal electronics improves.
>>
>>
>>
>> There are physical limits that are as inescapeable as the speed of light.
>> That's what Roger was referring to.
>
>
> Yes, that was what I was referring to. Quantum efficiency can be improved,
> but for a long time we haven't seen it. But assuming improvements
> there, we could see a perhaps factor of 2 improvement. That still
> won't make the small sensors as good as current DSLRs.
>
> Roger

Are you saying that you get the same number of photons at f4 as at f16?
If that were true, then cutting off the light completely would still
give you the same number of photons, which it certainly doesn't. Tell
any astronomer that he doesn't need more light collection ability, and
he will explain the error of your thinking.
If that were true, then a 8 inch reflector would be just as good as a
300 inch.


--
Ron Hunter rphunter@charter.net
Anonymous
April 20, 2005 7:06:06 AM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:
> Ron Hunter wrote:
>
>> Roger N. Clark (change username to rnclark) wrote:
>>
>>> Ron Hunter wrote:
>>>
>>>>
>>>> Yes. Very likely. Look back two years at what was available, and
>>>> compare it with now.
>>>>
>>>>
>>> No. The physical limit is here: the photon noise limit.
>>> There is room for a small improvement if quantum efficiency can
>>> be increased.
>>>
>>> Roger
>>
>>
>> I recall reading similar sentiments from experts in the field back
>> when they were saying 450 baud was the fastest modems would ever
>> go... I suspect the results will be similar to later results in that
>> realm. Technology has way of finding a way.
>
>
> Ron,
> the 450 baud thing was not a physical limit. This is not the same
> thing. Until someone rewrites the laws of physics, we have
> physical limits. Photon counting statistics is one of them.
> It says that the knowledge of the correct signal level has an
> error of the square root of the number of photons counted.
> That error appears as noise in digital camera images.
> Modern high quality digital cameras (whether DSLRs or
> small P&S) are photon noise limited.
> see:
> http://www.clarkvision.com/imagedetail/does.pixel.size....
> http://clarkvision.com/imagedetail/digital.signal.to.no...
>
> Roger

The 'laws' of physics are rewritten on a daily basis. As we learn more,
what we thought we knew before becomes greatly different. WE know so
little, that pronouncements about such things are often corrected in
only a year or two. I wouldn't be surprised to live to see quantum
sensors that produce an image we can't even imagine at this point.
Maybe even before we snap the shutter. Grin.


--
Ron Hunter rphunter@charter.net
Anonymous
April 20, 2005 12:01:18 PM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter wrote:

> Roger N. Clark (change username to rnclark) wrote:
>
>> Ron,
>> At a given f/stop, like f/4 you get the same number of photons
>> per square mm. No lens improvements will improve that.
>> Faster lenses are not the universal answer, as sometimes we
>> want depth of field.
>>
>> Roger
>
>
> Are you saying that you get the same number of photons at f4 as at f16?
> If that were true, then cutting off the light completely would still
> give you the same number of photons, which it certainly doesn't. Tell
> any astronomer that he doesn't need more light collection ability, and
> he will explain the error of your thinking.
> If that were true, then a 8 inch reflector would be just as good as a
> 300 inch.

No, I was saying at the same f/stop. For example, the 8x10 camera
with an f/4 lens, the 4x5 camera with the f/4 lens, the 35mm camera
with the f/4 lens, the ultra-compact camera with the f/4 lens
all collect the same number of photons per square mm in the
focal plane. The current optimum size for digital imaging is to have
pixels in the 6 to 8 micron range. That gives sufficient numbers
of photons onto each pixel in an image. There are other
reasons why this is good too, like lens performance, but
photon numbers is the main reason. Fix the pixel size
at no smaller than about 6 microns and then as you scale
the camera down, scale down the number of pixels. It is a
compromise. But if you want to scale down the pixels so you can
pack more of them, then the compromise is signal-to-noise, and
image quality. Simple physics. Until someone finds a way
to beat photon counting statistics, it is a fundamental
physical limit faced by camera manufacturers.

Roger
Anonymous
April 20, 2005 12:15:02 PM

Archived from groups: rec.photo.digital (More info?)

Ron Hunter wrote:

> The 'laws' of physics are rewritten on a daily basis. As we learn more,
> what we thought we knew before becomes greatly different. WE know so
> little, that pronouncements about such things are often corrected in
> only a year or two. I wouldn't be surprised to live to see quantum
> sensors that produce an image we can't even imagine at this point.
> Maybe even before we snap the shutter. Grin.

NO NO NO!
You have a misconception of laws of physics and scientific
discovery. Changing the laws of physics would be like
changing math so that 2 + 2 = 6.42. You find a way to
count 10,000 photons and know the signal level to better
than 100 photons (the noise), then you will have re-written
Poisson Statistics. The existence of a photon, electrons,
protons, their charges, the fields they produce and how
they interact, the speed of light, the Heisenberg
Uncertainty principle, E=mc^2, have been known for a long time
and are not changing. And not only that, modern physics is
showing how good all the fundamental physical laws are.
Probably the only cases of "rewriting" the laws of physics
was the introduction of quantum mechanics, and relativity.
But neither of these is actually a rewrite: they were simply a
greater understanding of physics under different conditions
and default to what we observe in the slow macroscopic
world we live in.

Roger
Anonymous
April 20, 2005 3:03:04 PM

Archived from groups: rec.photo.digital (More info?)

Both Roger and Ron are right in some sense, but concerning this
discussion Roger has the right conclusion.

Ron is, of course, right that the laws of physics (or better: what we
think that these laws are) may change. They changed fundamentally with
Einstein and again with Heisenberg (an yes: they were re-written!).
These were huge changes - but those will not happen every 20 years. In
the example, Ron mentions an increase of a modem speed - that's not a
change in the physics laws - that's only technical progress.

But even if our understanding of the physics laws will change in the
near future in a very fundamental way, it would be very unlikely that
e.g. this would completely throw away older knowledge (at least not for
most every day applications, as e.g. photography). It can not be ruled
out that it may still cause huge changes for our technologies - but
this would be on a very different timescale.
The discussion, so far, was more related to the nearer future (the next
10-20 years) and to progress in the technologies. All of this
technological progress will be within the framework of the Uncertainty
principle, E=mc^2, and Possion Statistics for counting photons.

.... therefore sensor size will still be very important in the next 10
years (at least!!)

Markus


Ron Hunter wrote:
> Roger N. Clark (change username to rnclark) wrote:
> > Ron Hunter wrote:
> >
> >> The 'laws' of physics are rewritten on a daily basis. As we learn

> >> more, what we thought we knew before becomes greatly different.
WE
> >> know so little, that pronouncements about such things are often
> >> corrected in only a year or two. I wouldn't be surprised to live
to
> >> see quantum sensors that produce an image we can't even imagine at

> >> this point.
> >> Maybe even before we snap the shutter. Grin.
> >
> >
> > NO NO NO!
> > You have a misconception of laws of physics and scientific
> > discovery. Changing the laws of physics would be like
> > changing math so that 2 + 2 = 6.42. You find a way to
> > count 10,000 photons and know the signal level to better
> > than 100 photons (the noise), then you will have re-written
> > Poisson Statistics. The existence of a photon, electrons,
> > protons, their charges, the fields they produce and how
> > they interact, the speed of light, the Heisenberg
> > Uncertainty principle, E=mc^2, have been known for a long time
> > and are not changing. And not only that, modern physics is
> > showing how good all the fundamental physical laws are.
> > Probably the only cases of "rewriting" the laws of physics
> > was the introduction of quantum mechanics, and relativity.
> > But neither of these is actually a rewrite: they were simply a
> > greater understanding of physics under different conditions
> > and default to what we observe in the slow macroscopic
> > world we live in.
> >
> > Roger
>
> Roger,
> You must remember that when I was in school, the nuclear age was
just
> beginning, and the 'laws' of physics changed DAILY. We didn't know
what
> they really were then, and we probably don't NOW. We still seem to
> think that light speed is a limit, but I would be willing to bet it
is
> NOT. For one thing, it is mutable. You can find reference to a
large
> number of scientists who gave lengthy explanations of why flying
faster
> than sound was impossible, physically. Before trains, people
believed
> that if you traveled faster than 20mph, you would die because you
> wouldn't be able to breathe.
>
> Don't be like the 'scientists' of the middle ages who took it as
"law"
> that spiders had 6 legs, because Socrates, or Aristotle, or some
other
> famous Greek SAID so. It limits thinking to things that have already

> been done.
>
>
> --
> Ron Hunter rphunter@charter.net
Anonymous
April 20, 2005 3:36:06 PM

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:
> Ron Hunter wrote:
>
>> The 'laws' of physics are rewritten on a daily basis. As we learn
>> more, what we thought we knew before becomes greatly different. WE
>> know so little, that pronouncements about such things are often
>> corrected in only a year or two. I wouldn't be surprised to live to
>> see quantum sensors that produce an image we can't even imagine at
>> this point.
>> Maybe even before we snap the shutter. Grin.
>
>
> NO NO NO!
> You have a misconception of laws of physics and scientific
> discovery. Changing the laws of physics would be like
> changing math so that 2 + 2 = 6.42. You find a way to
> count 10,000 photons and know the signal level to better
> than 100 photons (the noise), then you will have re-written
> Poisson Statistics. The existence of a photon, electrons,
> protons, their charges, the fields they produce and how
> they interact, the speed of light, the Heisenberg
> Uncertainty principle, E=mc^2, have been known for a long time
> and are not changing. And not only that, modern physics is
> showing how good all the fundamental physical laws are.
> Probably the only cases of "rewriting" the laws of physics
> was the introduction of quantum mechanics, and relativity.
> But neither of these is actually a rewrite: they were simply a
> greater understanding of physics under different conditions
> and default to what we observe in the slow macroscopic
> world we live in.
>
> Roger

Roger,
You must remember that when I was in school, the nuclear age was just
beginning, and the 'laws' of physics changed DAILY. We didn't know what
they really were then, and we probably don't NOW. We still seem to
think that light speed is a limit, but I would be willing to bet it is
NOT. For one thing, it is mutable. You can find reference to a large
number of scientists who gave lengthy explanations of why flying faster
than sound was impossible, physically. Before trains, people believed
that if you traveled faster than 20mph, you would die because you
wouldn't be able to breathe.

Don't be like the 'scientists' of the middle ages who took it as "law"
that spiders had 6 legs, because Socrates, or Aristotle, or some other
famous Greek SAID so. It limits thinking to things that have already
been done.


--
Ron Hunter rphunter@charter.net
Anonymous
April 20, 2005 8:41:41 PM

Archived from groups: rec.photo.digital (More info?)

Markus wrote:
> Both Roger and Ron are right in some sense, but concerning this
> discussion Roger has the right conclusion.
>
> Ron is, of course, right that the laws of physics (or better: what we
> think that these laws are) may change. They changed fundamentally with
> Einstein and again with Heisenberg (an yes: they were re-written!).
> These were huge changes - but those will not happen every 20 years. In
> the example, Ron mentions an increase of a modem speed - that's not a
> change in the physics laws - that's only technical progress.
>
> But even if our understanding of the physics laws will change in the
> near future in a very fundamental way, it would be very unlikely that
> e.g. this would completely throw away older knowledge (at least not for
> most every day applications, as e.g. photography). It can not be ruled
> out that it may still cause huge changes for our technologies - but
> this would be on a very different timescale.
> The discussion, so far, was more related to the nearer future (the next
> 10-20 years) and to progress in the technologies. All of this
> technological progress will be within the framework of the Uncertainty
> principle, E=mc^2, and Possion Statistics for counting photons.
>
> ... therefore sensor size will still be very important in the next 10
> years (at least!!)
>
> Markus
>

Five, maybe. Of course sensor size, or more accurately, pixel size,
will continue to be a factor, I suspect it will be less of one in five
years than it is today.



>
> Ron Hunter wrote:
>
>>Roger N. Clark (change username to rnclark) wrote:
>>
>>>Ron Hunter wrote:
>>>
>>>
>>>>The 'laws' of physics are rewritten on a daily basis. As we learn
>
>
>>>>more, what we thought we knew before becomes greatly different.
>
> WE
>
>>>>know so little, that pronouncements about such things are often
>>>>corrected in only a year or two. I wouldn't be surprised to live
>
> to
>
>>>>see quantum sensors that produce an image we can't even imagine at
>
>
>>>>this point.
>>>>Maybe even before we snap the shutter. Grin.
>>>
>>>
>>>NO NO NO!
>>>You have a misconception of laws of physics and scientific
>>>discovery. Changing the laws of physics would be like
>>>changing math so that 2 + 2 = 6.42. You find a way to
>>>count 10,000 photons and know the signal level to better
>>>than 100 photons (the noise), then you will have re-written
>>>Poisson Statistics. The existence of a photon, electrons,
>>>protons, their charges, the fields they produce and how
>>>they interact, the speed of light, the Heisenberg
>>>Uncertainty principle, E=mc^2, have been known for a long time
>>>and are not changing. And not only that, modern physics is
>>>showing how good all the fundamental physical laws are.
>>>Probably the only cases of "rewriting" the laws of physics
>>>was the introduction of quantum mechanics, and relativity.
>>>But neither of these is actually a rewrite: they were simply a
>>>greater understanding of physics under different conditions
>>>and default to what we observe in the slow macroscopic
>>>world we live in.
>>>
>>>Roger
>>
>>Roger,
>> You must remember that when I was in school, the nuclear age was
>
> just
>
>>beginning, and the 'laws' of physics changed DAILY. We didn't know
>
> what
>
>>they really were then, and we probably don't NOW. We still seem to
>>think that light speed is a limit, but I would be willing to bet it
>
> is
>
>>NOT. For one thing, it is mutable. You can find reference to a
>
> large
>
>>number of scientists who gave lengthy explanations of why flying
>
> faster
>
>>than sound was impossible, physically. Before trains, people
>
> believed
>
>>that if you traveled faster than 20mph, you would die because you
>>wouldn't be able to breathe.
>>
>>Don't be like the 'scientists' of the middle ages who took it as
>
> "law"
>
>>that spiders had 6 legs, because Socrates, or Aristotle, or some
>
> other
>
>>famous Greek SAID so. It limits thinking to things that have already
>
>
>>been done.
>>
>>
>>--
>>Ron Hunter rphunter@charter.net
>
>


--
Ron Hunter rphunter@charter.net
Anonymous
April 21, 2005 12:13:24 AM

Archived from groups: rec.photo.digital (More info?)

Markus wrote:

> Both Roger and Ron are right in some sense, but concerning this
> discussion Roger has the right conclusion.
>
> Ron is, of course, right that the laws of physics (or better: what we
> think that these laws are) may change. They changed fundamentally with
> Einstein and again with Heisenberg (an yes: they were re-written!).
> These were huge changes - but those will not happen every 20 years. In
> the example, Ron mentions an increase of a modem speed - that's not a
> change in the physics laws - that's only technical progress.
>
> But even if our understanding of the physics laws will change in the
> near future in a very fundamental way, it would be very unlikely that
> e.g. this would completely throw away older knowledge (at least not for
> most every day applications, as e.g. photography). It can not be ruled
> out that it may still cause huge changes for our technologies - but
> this would be on a very different timescale.
> The discussion, so far, was more related to the nearer future (the next
> 10-20 years) and to progress in the technologies. All of this
> technological progress will be within the framework of the Uncertainty
> principle, E=mc^2, and Possion Statistics for counting photons.

Marjus,
While this argument is really getting philosophical,
I would say that with Einstein and Heisenberg the laws of
physics were not rewritten. After all, we still have
Classical Newtonian physics; those laws were not thrown
away. We still have the duality nature of photons:
as particles and as waves. With Einstein and Heisenberg
we got grand extensions that expanded our understanding
into new realms, but we did not get a rewrite of
existing laws. And in fact, modern physics still defaults
to classical Newtonian physics in the slow macro world
of everyday experience we live in.

Roger
Anonymous
April 21, 2005 12:31:29 AM

Archived from groups: rec.photo.digital (More info?)

"Newbie" <chromallly@yahoo.com> ?????? ??? ??????
news:1113822990.199057.92160@l41g2000cwc.googlegroups.com...

> I wonder when we'll start seeing ultra-cameras that are in the 7 MP
> range, weighs 130g (fully equip) with 4X optical zoom, VGA movie
> capability like the Canon's, AF assist lamp, image stabilization and
> continuous shots ability? All that for under $400? Do you guys
> think we'll see that in the next 2 years?

You wont. Pesterbones with a built in camera will eat the low end of
the market in the next few years. As there are few who make both
cameras and phones, Sony is one of the few, market segmenting will not
work for long.

--
Paul Repacholi 1 Crescent Rd.,
+61 (08) 9257-1001 Kalamunda.
West Australia 6076
comp.os.vms,- The Older, Grumpier Slashdot
Raw, Cooked or Well-done, it's all half baked.
EPIC, The Architecture of the future, always has been, always will be.
Anonymous
April 21, 2005 12:49:29 AM

Archived from groups: rec.photo.digital (More info?)

[A complimentary Cc of this posting was sent to
Markus
<iandjohn@yahoo.com>], who wrote in article <1114020183.821926.220320@g14g2000cwa.googlegroups.com>:

> Both Roger and Ron are right in some sense, but concerning this
> discussion Roger has the right conclusion.

I'm pretty sure you mean well; however, *your* conclusion ;-) is
wrong. Roger's web site has a wealth of *extremely* useful data;
however, his conclusions on theoretical limits of the noise of digital
sensors are about an order of magnitude off. [His main problem is
that he uses terms "photon noise" and "electron noise"
interchangingly; this confusion moves the question of *actual* QE of
the sensors under his horizon; and with current sensor, QE is abysmal.]

See the recent thread on "theoretical limits" on this newsgroup with
for my estimates (partially based on Roger's raw data, partially on
independent data). What these calculations boil down is that the
performance of current half-frame sensors may be achieved (with
technology available today - at least in principle) with 2/3''
sensors.

Hope this helps,
Ilya
Anonymous
April 21, 2005 12:49:30 AM

Archived from groups: rec.photo.digital (More info?)

Ilya Zakharevich wrote:

> [A complimentary Cc of this posting was sent to
> Markus
> <iandjohn@yahoo.com>], who wrote in article <1114020183.821926.220320@g14g2000cwa.googlegroups.com>:
>
>
>>Both Roger and Ron are right in some sense, but concerning this
>>discussion Roger has the right conclusion.
>
>
> I'm pretty sure you mean well; however, *your* conclusion ;-) is
> wrong. Roger's web site has a wealth of *extremely* useful data;
> however, his conclusions on theoretical limits of the noise of digital
> sensors are about an order of magnitude off. [His main problem is
> that he uses terms "photon noise" and "electron noise"
> interchangingly; this confusion moves the question of *actual* QE of
> the sensors under his horizon; and with current sensor, QE is abysmal.]
>
> See the recent thread on "theoretical limits" on this newsgroup with
> for my estimates (partially based on Roger's raw data, partially on
> independent data). What these calculations boil down is that the
> performance of current half-frame sensors may be achieved (with
> technology available today - at least in principle) with 2/3''
> sensors.
>
> Hope this helps,
> Ilya

Ilya,
You continue to ignore multiple factors that I pointed out with
your and hand waving calculations. In numerous private emails,
I tried to help Ilya with calculating photons through the
atmosphere and to the camera to derive quantum efficiency
(a difficult thing to do even in the lab). His initial
really rough calculation was about a factor of 10 off.
I showed him multiple parts of his calculation that showed
factors of 2 hear, factors of two there, here a factor,
there a factor, and on and on. For example, his initial
calculation used a number for the bandwidth of the color filters
over sensor that I said from memory, but I gave
him the web link to the actual profiles. The bandwidth I
cited was off by a factor of 2. I corrected that number
and he waved his hands and comes up with the same number.
Same with his other errors. After I point out an error, he
waves his hands and comes up with the same number

He has not numerically integrated
over the solar response, the atmospheric transmission, the
surface reflectance, the lens transmittance, the sensor spectral
response, yet he thinks his answer is accurate. He is lucky
it is within a factor of ten. His conclusions that
on the order of 500,000 photons are incident on digital camera
sensors is simply not in line with any manufacturers data.
Somehow he is focused on proving his factor of ten yet
does not provide one credible reference that is in line with
these conclusions. He doesn't show rigorous calculation needed
for this problem.

On my pages I provide references with conclusions very close
to mine, independently derived. The full well capacities
of sensors I've tested are in line with manufacturers
specifications and with other independent tests.
Ilya has not shown any data or reference to data that
shows higher signal-to-noise results than I show.

Regarding electrons versus photons. It doesn't matter.
It is counting statistics. If a sensor is has a lower
quantum efficiency than 1 (duh!) those photons not converted
to electrons are not part of the Poisson statistics: it is
like they never existed for this problem. Only the photons
converted to electrons count in the Poisson statistics.

The QE of digital cameras is on the order of 30 to 50%. Film QE
is abysmal, not digital sensors. Back illuminated CCDs are
higher, and are primarily used in low light sensors (e.g.
by astronomers). If the full well of a digital camera pixel
is 50,000 electrons and the QE is 50%, then you need 100,000
photons to get 50,000 electrons. The noise is square root
50,000 not square root 100,000. What is important is
what you count, not what you miss.

Roger
http://www.clarkvision.com
April 21, 2005 4:17:43 AM

Archived from groups: rec.photo.digital (More info?)

"Newbie" <chromallly@yahoo.com> ruminated:
>After many days of surfing and researching until my eyes and neck
>hurts, I've finally decided on the Sony SD200. What I'm looking for
>was a digicam that I could take with me everyday like I would with my
>cellphone.

I suppose you mean the Canon SD200. I've used one for the
past six months. It has filled my needs well, and is far
better in every way than my previous compact camera, the
Canon S110.

Positives:
- Very fast in general operations--power on, focusing,
reviewing pictures, etc.

- 2+ fps continuous shot speed, for an unlimited # of frames

- Excellent movie mode, 640x480 30 fps

- Battery life is excellent (for a camera of this size), and
there is a very clever battery-life saving feature where the
motion sensor determines if the camera is in use or not to
decide whether the LCD should be on or off.


Negatives that could be improved upon without making the
camera larger:
- Annoying purple fringing on certain types of photos

- Since the camera's so light, it's hard to keep it steady
for photos. I wish the shutter release had a lighter
touch. In indoor conditions I usually use continuous-shot or
2-second timer delay to take photos (w/o flash), otherwise
there's a lot of blur due to unsteady hands from pressing
the shutter release.

- There are no manual controls for aperture and shutter
speed (except for long shutter speed)

- LCD is easy to scratch

There's decent competition from the ultra compact Panasonic,
Pentax, and Casio cameras.

Andrew
Anonymous
April 21, 2005 8:29:52 AM

Archived from groups: rec.photo.digital (More info?)

On Wed, 20 Apr 2005 20:13:24 -0600, in rec.photo.digital , "Roger N.
Clark (change username to rnclark)" <username@qwest.net> in
<42670C44.5030301@qwest.net> wrote:

>Markus wrote:
>
>> Both Roger and Ron are right in some sense, but concerning this
>> discussion Roger has the right conclusion.
>>
>> Ron is, of course, right that the laws of physics (or better: what we
>> think that these laws are) may change. They changed fundamentally with
>> Einstein and again with Heisenberg (an yes: they were re-written!).
>> These were huge changes - but those will not happen every 20 years. In
>> the example, Ron mentions an increase of a modem speed - that's not a
>> change in the physics laws - that's only technical progress.
>>
>> But even if our understanding of the physics laws will change in the
>> near future in a very fundamental way, it would be very unlikely that
>> e.g. this would completely throw away older knowledge (at least not for
>> most every day applications, as e.g. photography). It can not be ruled
>> out that it may still cause huge changes for our technologies - but
>> this would be on a very different timescale.
>> The discussion, so far, was more related to the nearer future (the next
>> 10-20 years) and to progress in the technologies. All of this
>> technological progress will be within the framework of the Uncertainty
>> principle, E=mc^2, and Possion Statistics for counting photons.
>
>Marjus,
>While this argument is really getting philosophical,
>I would say that with Einstein and Heisenberg the laws of
>physics were not rewritten. After all, we still have
>Classical Newtonian physics; those laws were not thrown
>away.

Newton's physics remains at a special case in a Universe with no mass
and objects of zero velocity. For small values Newton's physics
provides good enough answers, but it is wrong.

> We still have the duality nature of photons:
>as particles and as waves.

Still as in after Einstein.

>With Einstein and Heisenberg
>we got grand extensions that expanded our understanding
>into new realms, but we did not get a rewrite of
>existing laws. And in fact, modern physics still defaults
>to classical Newtonian physics in the slow macro world
>of everyday experience we live in.

The only physics that survived Einstein was the Maxwell Equations,
everything else changed.


--
Matt Silberstein

All in all, if I could be any animal, I would want to be
a duck or a goose. They can fly, walk, and swim. Plus,
there there is a certain satisfaction knowing that at the
end of your life you will taste good with an orange sauce
or, in the case of a goose, a chestnut stuffing.
Anonymous
April 21, 2005 11:21:11 AM

Archived from groups: rec.photo.digital (More info?)

[A complimentary Cc of this posting was sent to
Roger N. Clark (change username to rnclark)
<username@qwest.net>], who wrote in article <426709C9.40507@qwest.net>:
> > I'm pretty sure you mean well; however, *your* conclusion ;-) is
> > wrong. Roger's web site has a wealth of *extremely* useful data;
> > however, his conclusions on theoretical limits of the noise of digital
> > sensors are about an order of magnitude off.

> > See the recent thread on "theoretical limits" on this newsgroup with
> > for my estimates (partially based on Roger's raw data, partially on
> > independent data).

> You continue to ignore multiple factors that I pointed out with
> your and hand waving calculations. In numerous private emails,
> I tried to help Ilya with calculating photons through the
> atmosphere and to the camera to derive quantum efficiency

Apparently, you did not see the quoted about thread. As I pointed you
already, on google, it starts with

http://groups-beta.google.com/group/rec.photo.digital/m...

> His initial really rough calculation was about a factor of 10 off.

As the later, much simpler, calculation shows, it may have been off
about 1.5x .. 2x - but I did not intend it to be more precise than
this.

> On my pages I provide references with conclusions very close
> to mine, independently derived.

All what I could find discussed on your site is the electron count -
which is irrelevant to *theoretical limits*.

Of course, it is possible that I'm mistaken; if you can provide
other calculations of photon flow through "normal exposure" of 18%
gray for 100ISO, I will be very thankful. Especially if the answer
is much different...

> The full well capacities
> of sensors I've tested are in line with manufacturers
> specifications and with other independent tests.

I did not try to discredit your data about electron counts; most
probably your data is kosher; but it is not relevant to photon count.

> Regarding electrons versus photons. It doesn't matter.
> It is counting statistics. If a sensor is has a lower
> quantum efficiency than 1 (duh!) those photons not converted
> to electrons are not part of the Poisson statistics: it is
> like they never existed for this problem. Only the photons
> converted to electrons count in the Poisson statistics.

Sure; but the fault in your logic is that this paragraph discusses the
noise of *a particular sensor*. There is no doubt that a sensel which
gets less than 400 electrons for a particular exposure, cannot get S/N
above 20 for this pixel.

However, if you want to discuss "an ideal for a sensor", you need to
start with photon count, and only then proceed to electron count
(taking into account different inavoidable losses in different
components of the ).

> The QE of digital cameras is on the order of 30 to 50%.

The QE of a digital camera is a product of QE (i.e., transparency) of
the lens, QE of IR filter, QE of blur filter, average QE of cells of
the Bayer filter, and QE of the "photoelectric" part of the sensor.
OK, for interchangeable lens cameras one can forget about the first
factor; but all the others remain. In no way they can be as high as
30% with the current design.

> Film QE is abysmal,

Agreed; very much abysmal even in comparison with abysmal digital
sensors of today.

Hope this helps,
Ilya
Anonymous
April 22, 2005 1:14:04 AM

Archived from groups: rec.photo.digital (More info?)

Ilya Zakharevich wrote:

> Apparently, you did not see the quoted about thread. As I pointed you
> already, on google, it starts with
>
> http://groups-beta.google.com/group/rec.photo.digital/m...
>
>
> As the later, much simpler, calculation shows, it may have been off
> about 1.5x .. 2x - but I did not intend it to be more precise than
> this.

I did see this web page and I disagree with the content, method and
the way you you keep citing I am a factor of 10 off. In your
calculations, you use ultra precise numbers, like
"3.82082403851941e-20 W/m^2" and "spectral density
3065.57711860622 photon/(mkm*mkm^2)" for numbers that should at most
have one significant digit. You approximate complex curve
shapes by a single eye-balled average, with 15 significant
figures, as if to imply to others your calculations are precise.

You conclude that there are hundreds of thousands of photons
incident on a digital camera pixel. Your number of
"3065.57711860622" photons per square micron implies for the
Canon 1D Mark II sensor with 8.2 micron pixels, one would
have 8.2*8.2*3065 = 206,000 photons for an 18% gray card. or
206,000/0.18 = 1,140,000 photons full well But the measured
the full well is 52,000 electrons, so your implied quantum
efficiency = 50,000/1,140,000 = 0.05. Is this realistic?
No! Look up the quantum efficiency of CCD and CMOS detectors.
Here are some links:

http://www.ccd.com/ccd101.html

http://www.astro.psu.edu/xray/docs/cal_report/node89.ht...

http://www.src.le.ac.uk/instrumentation/solid_state/ccd...

CMOS sensors:
http://www-isl.stanford.edu/~abbas/group/papers_and_pub...

http://members.ozemail.com.au/~lovejoyt/300d.htm
Note this one concludes the Canon 300D in the red green
and value channels is 20, 40 and 40%, respectively.
Tested against a CCD with known QE, and assuming the IR block/AA
filter is 100% transmission, which it can't be. That means
the true efficiency must be on the order of ~25%, 45-50%,
45-50%.

So, your QE numbers are off by a factor of >4 to 10.

> I did not try to discredit your data about electron counts; most
> probably your data is kosher; but it is not relevant to photon count.

Actually it is. Electron count / QE = photons incident
on the sensor. Your page says:
"Poisson noise are often mixed up with electron Poisson noise,
thus erring close to an order of magnitude."
Photon count is not relevant to noise, strictly speaking.
It is electrons (converted from photons) that determines
noise. Like I said before, lost photons (not converted
to electrons) are like they never existed as far as the
final image and its noise is concerned.

> However, if you want to discuss "an ideal for a sensor", you need to
> start with photon count, and only then proceed to electron count
> (taking into account different inavoidable losses in different
> components of the ).

Not really. You only need to look at the QE. If the QE of
a canon cmos sensor (RGB) = 20, 40, 40%, then the system performance
could be improved by ~1/.25, ~1/.5 and ~1/.5 = 4, 2, 2,
assuming QE = 1 can be reached.

If this is what you are trying to say, then say it. Instead
you go on for pages of inaccurate calculations concluding the
wrong number of photons incident on detectors and wrong
quantum efficiencies.

You then scale your values to very small pixels as the theoretical
maximum: "0.768975" square micron. That is 0.88 micron square!
Your pixels will bleed signal into adjacent pixels due to diffraction.
If you use realistic numbers, and simply work from published
QE values, you get much different conclusions. And don't
forget diffraction!

> The QE of a digital camera is a product of QE (i.e., transparency) of
> the lens, QE of IR filter, QE of blur filter, average QE of cells of
> the Bayer filter, and QE of the "photoelectric" part of the sensor.

No, you mean system throughput. But that's just nomenclature.

Finally, on your page, you conclude one could get a
better S/N with a WYCW filters compared to an RGBG filters.
Like I said in my private email, work the propagation of
errors problem and show an example. You will find that
you don't win like you think.

Roger
Anonymous
April 22, 2005 1:14:05 AM

Archived from groups: rec.photo.digital (More info?)

"Roger N. Clark (change username to rnclark)" <username@qwest.net> writes:
> Tested against a CCD with known QE, and assuming the IR block/AA
> filter is 100% transmission, which it can't be. That means
> the true efficiency must be on the order of ~25%, 45-50%, 45-50%.

Digicams right now use filters over the R, G, and B pixels which each
throw away two thirds of the photons hitting that pixel, right? So
that would make the true efficiency around 10%.

What if we start seeing 3-ccd digicams with dichroic prisms instead of
filters, like serious video cameras have? Will that increase
efficiency?
Anonymous
April 22, 2005 2:56:27 AM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:

> "Roger N. Clark (change username to rnclark)" <username@qwest.net> writes:
>
>>Tested against a CCD with known QE, and assuming the IR block/AA
>>filter is 100% transmission, which it can't be. That means
>>the true efficiency must be on the order of ~25%, 45-50%, 45-50%.
>
>
> Digicams right now use filters over the R, G, and B pixels which each
> throw away two thirds of the photons hitting that pixel, right? So
> that would make the true efficiency around 10%.

The sensor quantum efficiency is unchanged by the filters put over the
sensor. System throughput is another story and includes the
transmission of the optics.

>
> What if we start seeing 3-ccd digicams with dichroic prisms instead of
> filters, like serious video cameras have? Will that increase
> efficiency?

You still need to split the light beams into three, and that
comes with a loss. The biggest would be color accuracy
if you used dichroic beam splitters, for example, which
is the only way to not lose a lot of light.
In high megapixel cameras, image alignment makes the
system extremely hard to do and keep stable with a
camera that is in use in field conditions. It would
also be larger than current systems.

Roger
Anonymous
April 22, 2005 2:56:28 AM

Archived from groups: rec.photo.digital (More info?)

"Roger N. Clark (change username to rnclark)" <username@qwest.net> writes:
> The sensor quantum efficiency is unchanged by the filters put over the
> sensor. System throughput is another story and includes the
> transmission of the optics.

Good point.

> You still need to split the light beams into three, and that comes
> with a loss. The biggest would be color accuracy if you used
> dichroic beam splitters, for example, which is the only way to not
> lose a lot of light. In high megapixel cameras, image alignment
> makes the system extremely hard to do and keep stable with a camera
> that is in use in field conditions. It would also be larger than
> current systems.

Hmm, multi-megapixel hybrid 3ccd video/still cameras with tiny little
ccd's seem to be all the rage now, as "3ccd" has become a consumer
marketing buzzword. Do they use something other than dichroic beam
splitters? Or are they subjecting themselves to image alignment
problems as well as sensor noise?

I wonder if anyone will start making monochrome digicams again. The
only serious one I know of was the Kodak DCS-660M, a 6MP camera that
cost something like $15K and is now discontinued. I'd like to buy a
monochrome D70 with a beefed up shutter, to use instead of a scanner
for document copying.
Anonymous
April 22, 2005 1:00:01 PM

Archived from groups: rec.photo.digital (More info?)

[A complimentary Cc of this posting was sent to
Roger N. Clark (change username to rnclark)
<username@qwest.net>], who wrote in article <42686BFC.5040308@qwest.net>:

> I did see this web page and I disagree with the content, method and
> the way you you keep citing I am a factor of 10 off. In your
> calculations, you use ultra precise numbers, like
> "3.82082403851941e-20 W/m^2" and "spectral density
> 3065.57711860622 photon/(mkm*mkm^2)" for numbers that should at most
> have one significant digit. You approximate complex curve
> shapes by a single eye-balled average, with 15 significant
> figures, as if to imply to others your calculations are precise.

Did I? If you read the article, you would see what I write on the topic:

[All intermediate numbers are given with quite high precision; of
course, due to approximations in assumptions, very few significant
digits are trustworthy.]

Moreover, I explained why "the eye-balled average" will do.

> 206,000/0.18 = 1,140,000 photons full well But the measured
> the full well is 52,000 electrons, so your implied quantum
> efficiency = 50,000/1,140,000 = 0.05. Is this realistic?

Yes.

> http://members.ozemail.com.au/~lovejoyt/300d.htm
> Note this one concludes the Canon 300D in the red green
> and value channels is 20, 40 and 40%, respectively.

No, this is not what the site says. These are *peak values*; you need
to multiply them by the effective width, which would be about 1/5 of
the visible spectrum. This would give efficiency of about 0.04, 0.08,
0.08. [You know where to find the shapes of spectral sensitivity
curves for the sensor, so you can easily get exact numbers.]

> > I did not try to discredit your data about electron counts; most
> > probably your data is kosher; but it is not relevant to photon count.

> Actually it is. Electron count / QE = photons incident
> on the sensor.

Since you do not know the "throughput QE" of the sensor assembly, this
is not useful in any way.

> Photon count is not relevant to noise, strictly speaking.
> It is electrons (converted from photons) that determines
> noise.

Actually, if you know the math - no (though this is not directly
related to the topic we discuss). See [P.S.] below.

> Like I said before, lost photons (not converted to electrons) are
> like they never existed as far as the final image and its noise is
> concerned.

Like I said before, this is only applicable if you consider *one
particular sensor*, but not relevant to describing possible
performance of other sensors. What is lost in one sensor is not lost
in another.

> If the QE of a canon cmos sensor (RGB) = 20, 40, 40%, then the
> system performance could be improved by ~1/.25, ~1/.5 and ~1/.5 = 4,
> 2, 2, assuming QE = 1 can be reached.

Well, since QEs are not what you cite, these numbers are not relevant.

> > The QE of a digital camera is a product of QE (i.e., transparency) of
> > the lens, QE of IR filter, QE of blur filter, average QE of cells of
> > the Bayer filter, and QE of the "photoelectric" part of the sensor.

> No, you mean system throughput. But that's just nomenclature.

Sorry, can't understand what you mean here... My calculations (as
stated many times) concert only number of photons which reach the
sensor.

If your calculations are about the number of photons which reach the
"photoelectric component" of the sensor, then these numbers are
irrelevant to the maximal possible sensitivity of the sensor (unless
the transparencies of IR filter, blur filter, Bayer filter are maximal
possible - which, as I had shown in my article, they are not).

> Finally, on your page, you conclude one could get a
> better S/N with a WYCW filters compared to an RGBG filters.
> Like I said in my private email, work the propagation of
> errors problem and show an example. You will find that
> you don't win like you think.

Like I said in my private email (and like it is written in the cited
article), in this claim you do not take into account that eye
sensitivity to chrominance noise is practically 0. So only luminance
noise matters.

You can do the "propagation of errors" calculation yourselves; since
you did not, here is one example: consider 7500 photons coming to RGB
Bayer matrix with transparency of each channel 33% (just a random
number - but of correct order of magnitude); assume QE=1. Each cell
gets 2500 photons; the noise is 50 photons. To simplify numbers,
assume that luminance is R+G+B; then one gets noise of 50*sqrt(3)
with the S/N of 50*sqrt(3).

Now consider a Bayer filter with Purple/Yellow/Cyan cells (Purple
passes R+B, Yellow R+G, Cyan G+B). Now each cell gets a sum of two
RGB channels, i.e., 5000 photons, with noise 50*sqrt(2). The formula
for luminance becomes (P+Y+C)/2; thus one gets noise 50*sqrt(3/2),
with S/N of 50*sqrt(3*2). Increase of sqrt(2); exactly as expected
with twice the number of photons coming to the sensor.

Hope this helps,
Ilya

P.S.

Here are the details on the relation of final noise to electron
count: The approximation that final noise is

sqrt(number of photons which generated output electrons)

works IF each photon generates 0 or 1 electrons. Since I do not know
all the details of the throughway between captured photons and ADC,
I cannot be exactly sure; but I suspect that ADC gets more than 1
electron for each electron generated in the sensor (i.e., that there
is some amplifier in between).

I doubt this amplifier "amplifies exactly" (like generating exactly
30 output electrons for every input electron); most probably it
would, e.g., generate 29, 30, or 31 output electrons. Then this
discrepancy is an additional source of "const*sqrt(count) noise"; so
any measurement of full well via estimations of sqrt-component of
the noise will be biased by this noise.
Anonymous
April 22, 2005 6:50:56 PM

Archived from groups: rec.photo.digital (More info?)

On 21 Apr 2005 22:06:43 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid&gt; wrote:

>Hmm, multi-megapixel hybrid 3ccd video/still cameras with tiny little
>ccd's seem to be all the rage now, as "3ccd" has become a consumer
>marketing buzzword. Do they use something other than dichroic beam
>splitters? Or are they subjecting themselves to image alignment
>problems as well as sensor noise?

I'm not edicated enough to throw around big words, but I do know that
video (even HD) doesn't meet the requirements of most P&S users have.
Wait, that didn't come out right...
Video (even HD) doesn't meet the requirements of the dedicated
amateur, much less a professional, unless low quality is what's
specifically wanted.
Yeah, that's better. :-)

--
Bill Funk
Change "g" to "a"
Anonymous
April 22, 2005 11:02:18 PM

Archived from groups: rec.photo.digital (More info?)

Big Bill wrote:
> On 21 Apr 2005 22:06:43 -0700, Paul Rubin
> <http://phr.cx@NOSPAM.invalid&gt; wrote:
>
>
>>Hmm, multi-megapixel hybrid 3ccd video/still cameras with tiny little
>>ccd's seem to be all the rage now, as "3ccd" has become a consumer
>>marketing buzzword. Do they use something other than dichroic beam
>>splitters? Or are they subjecting themselves to image alignment
>>problems as well as sensor noise?
>
>
> I'm not edicated enough to throw around big words, but I do know that
> video (even HD) doesn't meet the requirements of most P&S users have.
> Wait, that didn't come out right...
> Video (even HD) doesn't meet the requirements of the dedicated
> amateur, much less a professional, unless low quality is what's
> specifically wanted.
> Yeah, that's better. :-)
>
It depends on how you want to use the video. If you plan to project it
on a theater screen, BAD. If you plan to show it on a TV, then 640x480
is more than good enough.
Maybe when the technology gets good enough to scan 80MP at 30fps, and
store that data on your terabyte flash card, you will get what you want.
It will probably be a few years yet.


--
Ron Hunter rphunter@charter.net
!