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Nikon Super CoolScan 4000 ED - some questions

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Anonymous
September 12, 2005 1:51:45 PM

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

Does anybody here have some experience with this scanner? I have
a few questions.

I got this scanner to scan all my slides and am not quite sure
about the optimal settings.

1. I find that this scanner, like practically every other, isn't
as sharp as the manufacturer states. It cannot nearly reproduce
a good slide in all of its resolution. Sharp, fine text, for
example becomes mushy and, in extreme cases, unreadable.

I conclude therefore that it serves no purpose to set the
scanner to its full native resolution. The pictures would only
be bigger and unsharp. So I reduced the resolution from 4,000 to
2,400 dpi. Even at that resolution the results are clearly very
unsharp.

Does this make sense?

2. Has anybody experimented with the sharpening function, the
one called unsharp masking? Does this in fact compensate for a
scanner shortcoming or does it only exaggerate edges? What did
you find to be the best settings?

3. When scanning with 8 bits per color, rather than the full
color depth, does it still make sense to do multiple passes per
slide? Or is the sensor noise lower than what can be represented
in 8 bits per color?

4. While scanning, the scan software uses 100% of an Athlon 64
3000+ processor. Is this normal? Is the processor really the
bottleneck? Anything I could set up differently to make it scan
faster?

5. Any other hints?

Hans-Georg

--
No mail, please.
Anonymous
September 12, 2005 1:51:46 PM

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

Regarding 'sharpness'. I have used a Nikon 5000ED (same res as your
4000), and have found that it easily resolves grain. If your scanner is
not dirty or malfunctioning, or just not focused, it should be quite
sharp. Can you see the grain when view at 'actual pixels'? Also, if
your slides are heavily curved, that may be the problem. There can be
depth of field issues.

You may want to post your questions to 'comps.periphs.scanners' as that
is where the scanner community mostly is.

W
September 13, 2005 5:07:34 AM

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

Hans-Georg Michna wrote:

> Does anybody here have some experience with this scanner? I have
> a few questions.
>
> I got this scanner to scan all my slides and am not quite sure
> about the optimal settings.
>
> 1. I find that this scanner, like practically every other, isn't
> as sharp as the manufacturer states. It cannot nearly reproduce
> a good slide in all of its resolution. Sharp, fine text, for
> example becomes mushy and, in extreme cases, unreadable.
>


Sounds like you have focus problems or the film isn't flat. Read the manual
on the software, use the "ctrl" while clicking the focus button and you can
select different spots to focus on. If they vary a bunch (over 20-30
points), you'll never get the whole thing sharp.

>
> 3. When scanning with 8 bits per color, rather than the full
> color depth, does it still make sense to do multiple passes per
> slide?

I'd only do this if you have REALLY dense area's that show noise.

>
> 4. While scanning, the scan software uses 100% of an Athlon 64
> 3000+ processor. Is this normal? Is the processor really the
> bottleneck? Anything I could set up differently to make it scan
> faster?

Do you have AV software running? That can cause all sorts of problems from
what I've read with scanning.

I have the big brother LS 8000 and it scans everything I can see of the
film..

--

Stacey
Related resources
Anonymous
September 14, 2005 3:27:45 AM

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

In article <6qcai117rp7s50tjqk19fjha9209ecdbi3@4ax.com>, Hans-Georg
Michna <hans-georgNoEmailPlease@michna.com> writes
>Does anybody here have some experience with this scanner? I have
>a few questions.
>
Yup, years of experience with it. ;-)

>I got this scanner to scan all my slides and am not quite sure
>about the optimal settings.
>
>1. I find that this scanner, like practically every other, isn't
>as sharp as the manufacturer states.

Well that raises an interesting question: Do you know what "as sharp as
the manufacturer states" should look like? If you don't (and too many
people think it means you should get adjacent black and white pixels -
it doesn't!) how can you determine that it isn't as sharp as it should
be?

>It cannot nearly reproduce
>a good slide in all of its resolution. Sharp, fine text, for
>example becomes mushy and, in extreme cases, unreadable.
>
OK, you clearly have a problem with focus or dirt. The LS-4000 is
particularly fussy about film flatness, so if your film is curved by a
couple of millimetres then it will not maintain focus across the entire
frame.

Assuming your film is flat, is the scanner set to focus automatically
before each scan or preview is made? If you have inadvertently switched
this option off in the preferences section then the scanner will just
hold the last focus position it had - which could be miles (well, not
quite that far) from the correct focus position.

You can set the auto-focus on any particular part of the image using the
focus position icon in the scan software, or manually adjust the focus
through a range of values - though I have never found a real use for
this latter control other than assessing the amount of film curvature.

>I conclude therefore that it serves no purpose to set the
>scanner to its full native resolution.

I conclude the opposite - that you have a problem, not that the scanner
is incapable of delivering its native resolution.

>The pictures would only
>be bigger and unsharp. So I reduced the resolution from 4,000 to
>2,400 dpi. Even at that resolution the results are clearly very
>unsharp.
>
>Does this make sense?
>
Yes - it suggests you either aren't focussing or your scanner has
dirt/dust on the mirrors.

The easiest diagnosis of dirt/dust is to scan a frame edge against a
white background on slide film. eg. the black gap between two lighter
frames or the edge of the slide mount with light subject matter at the
edge of the frame. If you have dirty mirrors or optics then you will
notice a smearing of the lighter portions of the image into the black
frame. If this is the problem then there is no alternative to having
the scanner stripped and cleaned - something you can do yourself if you
are confident of working with optical instruments, but otherwise it is
better to pay someone who is.

>2. Has anybody experimented with the sharpening function, the
>one called unsharp masking? Does this in fact compensate for a
>scanner shortcoming or does it only exaggerate edges? What did
>you find to be the best settings?
>
All scanners have shortcomings in terms of their image sharpness, it is
a fact of life and USM is one method of compensating for this. I find
that something around 5% intensity, 5% halo width and 5-10 levels of
threshold fairly acceptable, but often scan without any USM.

>3. When scanning with 8 bits per color, rather than the full
>color depth, does it still make sense to do multiple passes per
>slide? Or is the sensor noise lower than what can be represented
>in 8 bits per color?
>
Yes, it still makes sense to use multisampling - this scanner does not
do multiple passes, it multisamples in a single pass. The reason why
this is still worth doing is because the noise is, of course, more than
the quantisation noise of the 14-bit ADC and this is for a linear scan.
Gamma compensation for normal use results in the noise from all sources,
including this quantisation, being amplified in the shadows. However
you will need a fairly dense film to be able to show the difference -
and you haven't a hope if you are getting scattered light from dirty
optics. Also, measurements show that for near saturated scans,
corresponding to shadows on negatives, the photon noise itself is
equivalent to just over 8-bits for the CCD. This can be improved by
multisampling, to over 10-bits at 16x. You will probably see more gain
from multisampling negatives than slides, because the dynamic range of
the scanner is very good.

>4. While scanning, the scan software uses 100% of an Athlon 64
>3000+ processor. Is this normal? Is the processor really the
>bottleneck? Anything I could set up differently to make it scan
>faster?
>
No idea, I don't use Athlons.

>5. Any other hints?

RTFMs - if you don't have copies then download them from the Nikon
website. There are two - one for the scanner itself and one for the
Nikonscan software.

Obtain and install the latest firmware update (v1.10)

Obtain and install the latest version of NikonScan (v4.02)
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 14, 2005 3:59:31 AM

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

On 12 Sep 2005 06:41:18 -0700, "winhag@yahoo.com"
<winhag@yahoo.com> wrote:

>Regarding 'sharpness'. I have used a Nikon 5000ED (same res as your
>4000), and have found that it easily resolves grain. If your scanner is
>not dirty or malfunctioning, or just not focused, it should be quite
>sharp. Can you see the grain when view at 'actual pixels'? Also, if
>your slides are heavily curved, that may be the problem. There can be
>depth of field issues.

It does show grain, but there is a lot of softness. An edge that
is fairly sharp on the slide covers several pixels, something
like 4, on the scan. Slides are in glass, but taking them out
doesn't give any better results. They should at least be sharp
in the center, but they never quite are.

I must admit that I have yet to see any scanner that reproduces
a one pixel wide line as a one pixel line. Gues I need 8,000 dpi
to get a sharp 4,000 dpi picture.

>You may want to post your questions to 'comps.periphs.scanners' as that
>is where the scanner community mostly is.

Thanks! That's a useful hint. Will do this.

Hans-Georg

--
No mail, please.
Anonymous
September 14, 2005 3:59:34 AM

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

On Tue, 13 Sep 2005 01:07:34 -0400, Stacey <fotocord@yahoo.com>
wrote:

>Hans-Georg Michna wrote:

>> 1. I find that this scanner, like practically every other, isn't
>> as sharp as the manufacturer states. It cannot nearly reproduce
>> a good slide in all of its resolution. Sharp, fine text, for
>> example becomes mushy and, in extreme cases, unreadable.

>Sounds like you have focus problems or the film isn't flat. Read the manual
>on the software, use the "ctrl" while clicking the focus button and you can
>select different spots to focus on. If they vary a bunch (over 20-30
>points), you'll never get the whole thing sharp.

Stacey,

thanks for your reply! I had already tried that, but except for
a few far out of focus scans this is not the case. The autofocus
works well and the results are repeatable.

I think that this scanner is no better than any other and
exaggerates its resolution by a factor of 2. Scanning at 2,000
dpi, rather than its rated 4,000, yields reasonably, though
still not perfectly sharp pictures.

Try this. Put a piece of paper into a slide and scan the edge.
Then check how many pixels it covers. It's at least 4 to 4 grey
pixels between the black and the white area, rather than 1 or
perhaps 2.

>> 3. When scanning with 8 bits per color, rather than the full
>> color depth, does it still make sense to do multiple passes per
>> slide?

>I'd only do this if you have REALLY dense area's that show noise.

Thanks, thought so. I don't do it. It seems that the noise from
the film overwhelms the noise from the sensor, at least when I
scan at 2,000 dpi, half the rated resolution. Thus four pixels
become one and a lot of noise is cancelled out.

>> 4. While scanning, the scan software uses 100% of an Athlon 64
>> 3000+ processor. Is this normal? Is the processor really the
>> bottleneck? Anything I could set up differently to make it scan
>> faster?

>Do you have AV software running? That can cause all sorts of problems from
>what I've read with scanning.

No AV running in the background.

>I have the big brother LS 8000 and it scans everything I can see of the
>film..

Nice! Ever looked at the processor load? I have this impression
that the processor load is genuine, because any further load
actually slows the scan. Those scanners do make use of the
processor.

I have now, after a few tests, switched on the Digital ICE4 and
am deeply impressed. Never switched it off again.

Hans-Georg

--
No mail, please.
Anonymous
September 14, 2005 4:12:36 AM

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

In article <bciei11t1b1c53mptu1j1058sbc0ci2npm@4ax.com>, Hans-Georg
Michna <hans-georgNoEmailPlease@michna.com> writes
>
>Try this. Put a piece of paper into a slide and scan the edge.
>Then check how many pixels it covers. It's at least 4 to 4 grey
>pixels between the black and the white area, rather than 1 or
>perhaps 2.

Precisely the point I was making in my other post - you *don't* know
what the manufacturer's specification should look like!

Resolving something does *NOT* mean reproducing it at 100% contrast -
which would be the case of having the single pixel transition between a
black and white edge you think you should be getting!

No visible optic in itself can achieve that, let alone one of limited
size in a scanner at 4000ppi (2000cy/in) resolution! The lens has a
finite MTF as does the CCD - all of which reduce the rate of change of
edges. Just for reference, a *perfect* f/4 lens will only be capable of
resolving 2000lppi at around 75% of the contrast of the full black to
white transition - and that is peak green light, it will be worse at the
red end. I don't know what the f/# is of the lens in the LS-4000, but I
doubt it is much faster than f/4.

A quick look at some published measurements from a number of LS-4000
scanners shows them to be among the best resolving units available, with
MTF-50 figures around 22-25cy/mm. That means that the scanner will
reproduce a bar pattern (more accurately a sine wave) of 560-640lppi at
50% of the contrast of the original. Since the scanner is capable of
resolving 2000lppi, then 4 pixels to achieve full contrast transition is
a reasonable comparison. However, the scanner could still be capable of
*resolving* 2000lppi even if it took 10 or 20 pixels to transition peak
white to black - unlikely, but certainly possible.

Your general dissatisfaction with scanners appears to be down to a
misunderstanding of what the manufacturers are offering in their
specifications.

What I find more surprising is that you have somehow convinced yourself
that so much more information is available on the film to begin with!
Try this for comparison: view your scanned edge transition or text on
your screen at 100% magnification, so that you can see the softness you
are concerned about. Typical displays these days are around 96ppi - so
the image size from a full scanned 35mm frame would be around
40x60inches. Now, go into a projection room and project your slide at
that same size and view it from the same distance as you do the monitor
- about 10-12". The original will, of course, look a little sharper
but, if your scanner is functioning correctly, it won't be that much
sharper and it will surprise you just how little information that the
scanner is not capable of lifting off the film.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
September 14, 2005 5:08:01 AM

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

Hans-Georg Michna wrote:

> I have now, after a few tests, switched on the Digital ICE4 and
> am deeply impressed. Never switched it off again.
>

Yep, it's amazing how well it works! I suppose since I'm scanning mostly
6X4.5 and 6X9 film the rez issues don't seem bad? I have done some 8X10
prints from 35mm film scans and they look really good, about as far as I'd
ever go with 35mm film anyway..
--

Stacey
September 14, 2005 5:13:36 AM

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

Hans-Georg Michna wrote:

> On 12 Sep 2005 06:41:18 -0700, "winhag@yahoo.com"
>
> I must admit that I have yet to see any scanner that reproduces
> a one pixel wide line as a one pixel line.

Stop pixel peeping and look at the prints..

--

Stacey
Anonymous
September 15, 2005 10:47:35 PM

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

On Wed, 14 Sep 2005 01:13:36 -0400, Stacey <fotocord@yahoo.com>
wrote:

>Hans-Georg Michna wrote:

>> I must admit that I have yet to see any scanner that reproduces
>> a one pixel wide line as a one pixel line.

>Stop pixel peeping and look at the prints..

Stacey,

no need to. I can compare the original slide under a magnifying
glass with the scan. The results from the Nikon 4000 ED don't
even come close to reproducing the sharpness of the slide.

But then this is still a relatively cheap scanner, probably
meant for the ambitious amateur, and for that it may be good
enough.

Hans-Georg

--
No mail, please.
Anonymous
September 15, 2005 10:47:36 PM

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

On Tue, 13 Sep 2005 23:27:45 +0100, Kennedy McEwen
<rkm@nospam.demon.co.uk> wrote:

>In article <6qcai117rp7s50tjqk19fjha9209ecdbi3@4ax.com>, Hans-Georg
>Michna <hans-georgNoEmailPlease@michna.com> writes

>>Does anybody here have some experience with this scanner? I have
>>a few questions.

>Yup, years of experience with it. ;-)

Kennedy,

thanks for your very interesting replies! I'll try to comment on
both in this message.

>Well that raises an interesting question: Do you know what "as sharp as
>the manufacturer states" should look like? If you don't (and too many
>people think it means you should get adjacent black and white pixels -
>it doesn't!) how can you determine that it isn't as sharp as it should
>be?

I think we can lay this question to rest. What I understand when
I read 4,000 dpi is that those pixels represent the scanned
picture optimally. For example, a perfect black-white edge
should have only one row of grey pixels. But in the real world
they don't do that.

No sense discussing this much, things are as they are. I already
wrote in my first message that all scanners I know exaggerate
their resolution this way.

>>It cannot nearly reproduce
>>a good slide in all of its resolution. Sharp, fine text, for
>>example becomes mushy and, in extreme cases, unreadable.

>OK, you clearly have a problem with focus or dirt. The LS-4000 is
>particularly fussy about film flatness, so if your film is curved by a
>couple of millimetres then it will not maintain focus across the entire
>frame.

Glass frames, but when I take the film out or scan non-glass
frames, the results are the same. I tested that, of course.

>Assuming your film is flat, is the scanner set to focus automatically
>before each scan or preview is made? If you have inadvertently switched
>this option off in the preferences section then the scanner will just
>hold the last focus position it had - which could be miles (well, not
>quite that far) from the correct focus position.

I'm fully aware of when the scanner performs its autofocus
procedure. I keep finding some slides that are out of focus and
have to rescan them. Some came out that way because there is no
contrast in the center, and I have to choose a different focus
point, but for most the reason is inexplicable, since a
subsequent scan under identical conditions produces a normally
sharp picture. No big deal.

>The easiest diagnosis of dirt/dust is to scan a frame edge against a
>white background on slide film. eg. the black gap between two lighter
>frames or the edge of the slide mount with light subject matter at the
>edge of the frame. If you have dirty mirrors or optics then you will
>notice a smearing of the lighter portions of the image into the black
>frame. If this is the problem then there is no alternative to having
>the scanner stripped and cleaned - something you can do yourself if you
>are confident of working with optical instruments, but otherwise it is
>better to pay someone who is.

Thanks for this information! It is very useful and interesing!

In my case the scanner seems to be fine and not too dirty.

>[...] Also, measurements show that for near saturated scans,
>corresponding to shadows on negatives, the photon noise itself is
>equivalent to just over 8-bits for the CCD. This can be improved by
>multisampling, to over 10-bits at 16x. You will probably see more gain
>from multisampling negatives than slides, because the dynamic range of
>the scanner is very good.

Interesting again. I wasn't sure about how many photons each
sensor pixel gets, but we're apparently near the limit.

>RTFMs - if you don't have copies then download them from the Nikon
>website. There are two - one for the scanner itself and one for the
>Nikonscan software.

Did that already. Needed the manual for some information.

>Obtain and install the latest firmware update (v1.10)

v1.10 was already loaded.

>Obtain and install the latest version of NikonScan (v4.02)

Had to do that anyway, because v3 doesn't run on Windows XP.


On Wed, 14 Sep 2005 00:12:36 +0100, Kennedy McEwen
<rkm@nospam.demon.co.uk> wrote:

>In article <bciei11t1b1c53mptu1j1058sbc0ci2npm@4ax.com>, Hans-Georg
>Michna <hans-georgNoEmailPlease@michna.com> writes

>[Precise, interesting and useful information snipped]

>Your general dissatisfaction with scanners appears to be down to a
>misunderstanding of what the manufacturers are offering in their
>specifications.

Let's say an unfulfilled hope that those 4,000 pixels per inch
should reproduce the information on the slide as well as
possible. Guess I'd have to buy an 8,000 or 16,000 dpi scanner
to get a real 4,000 dpi resolution.

But I understand your points and have to accept that the scanner
manufacturers do it the way we see here.

>What I find more surprising is that you have somehow convinced yourself
>that so much more information is available on the film to begin with!
>Try this for comparison: view your scanned edge transition or text on
>your screen at 100% magnification, so that you can see the softness you
>are concerned about. Typical displays these days are around 96ppi - so
>the image size from a full scanned 35mm frame would be around
>40x60inches. Now, go into a projection room and project your slide at
>that same size and view it from the same distance as you do the monitor
>- about 10-12". The original will, of course, look a little sharper
>but, if your scanner is functioning correctly, it won't be that much
>sharper and it will surprise you just how little information that the
>scanner is not capable of lifting off the film.

Here the truth is obvious. I look at a slide that contains some
small black text on a white background, and I see that the slide
reproduces that text impressively sharply.

Then I scan the slide at 4,000 dpi, and the text is barely
readable or not readable any more, even though the number of
pixels per letter would easily suffice to have it readable. In
fact, there is a lot of cross-feed from one pixel to the next,
either because the optics are not sharp enough, could also be
out of focus, or because there is some cross-feed on the sensor.

But as I wrote, effectively a 4,000 dpi scanner like this is
unable to reproduce the full sharpness of a slide, and I have to
accept that grudgingly.

I'm still under the impression that this scanner produces
reasonably sharp pictures at 2,000 dpi. Of course raising the
resolution always adds some information to the result, but
raising it to the native 4,000 dpi yields rather little. Egdes,
for example, don't become any sharper.

Let me post an example. Please have a look at

http://www.michna.com/temp/images/india0203_detail_2000...
http://www.michna.com/temp/images/india0203_detail_4000...

The first, 2,000 dpi scan was scanned earlier and taken from
http://www.michna.com/photos/ . It was an automatic scan through
the slide feeder. The second, 4,000 dpi scan I have taken just
now for comparison.

The samples show that the autofocus seems to be imperfect,
because the higher resolution scan is actually less sharp than
the 2,000 dpi scan. That's another factor one has to put up
with.

The text on the bus is readable, but when you look at the
original slide, there is no comparison. Unfortunately I can't
show it to you, but the text is pitch-black and perfectly sharp,
totally incomparable to the scans. The scanner does not
reproduce the quality of the slide by far. The film is
Ektachrome 100, by the way. If the camera can do it, why not the
slide scanner?

Anyway, what you can see is that it serves no purpose to scan at
4,000 dpi. The pictures do not contain significantly more
information than 2,000 dpi scans.

Hans-Georg

--
No mail, please.
Anonymous
September 16, 2005 4:43:38 AM

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

In article <l33ji118l0n73b8379v1jso381hnna5fo1@4ax.com>,
Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> wrote:
>Anyway, what you can see is that it serves no purpose to scan at
>4,000 dpi. The pictures do not contain significantly more
>information than 2,000 dpi scans.

For comparison, here are a couple of scans on my LS-4000:

<http://misc.hq.phicoh.net/edge/Image1a.tif&gt;
and
<http://misc.hq.phicoh.net/edge/Image1b.tif&gt;
are 4000 ppi crops
<http://misc.hq.phicoh.net/edge/Image1f.tif&gt;
gives and overview of the entire frame.

<http://misc.hq.phicoh.net/edge/Image2a.tif&gt;
is a crop of a scan of a razor blade. See
<http://misc.hq.phicoh.net/edge/notes.txt&gt;
for more details


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency
Anonymous
September 16, 2005 9:42:24 AM

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

In article <l33ji118l0n73b8379v1jso381hnna5fo1@4ax.com>, Hans-Georg
Michna <hans-georgNoEmailPlease@michna.com> writes
>
>Kennedy,
>
>thanks for your very interesting replies! I'll try to comment on
>both in this message.
>
>>Well that raises an interesting question: Do you know what "as sharp as
>>the manufacturer states" should look like? If you don't (and too many
>>people think it means you should get adjacent black and white pixels -
>>it doesn't!) how can you determine that it isn't as sharp as it should
>>be?
>
>I think we can lay this question to rest. What I understand when
>I read 4,000 dpi is that those pixels represent the scanned
>picture optimally. For example, a perfect black-white edge
>should have only one row of grey pixels. But in the real world
>they don't do that.
>
>No sense discussing this much, things are as they are. I already
>wrote in my first message that all scanners I know exaggerate
>their resolution this way.

It is worth noting that this interpretation of resolution, whilst not
unique to yourself, is incorrect. Two forms of resolution take place in
scanners - sampling resolution (which I prefer to call sampling density
to avoid confusion) and optical resolution. Sampling resolution or
density is the headline number that the manufacturers hit you with and
is basically the number of pixels that the scanner samples per inch. It
doesn't say anything about the actual performance of the scanner or how
distinct any pixel is from adjacent pixels. That comes down to optical
resolution and, as I am sure you have guessed, manufacturers are less
than vociferous in making customers, let alone potential customers,
aware of that. There are good reasons for this - people are stupid and
will buy a scanner from a manufacturer that claims 4,000ppi resolution
than one who offers only 1500cy/in resolution.

However even optical resolution isn't anything close to your estimate.
Optical resolution is based on the century old Rayleigh criterion - how
far apart can two point sources be when the system just manages to
distinguish them as separate objects rather than a single coalesced
mass. So, your single grey pixel across an edge isn't realistic at all.
You might have two black dots the size of several pixel size on a white
background and move them closer together scanning at each separation.
When you get each dot with a few light pixels in between then you will
probably get a good contrasty signal. However that isn't the optical
resolution - you have to move the dots closer still until they can just
be identified as separate instead of a single rectangular blob. At this
point, the signal between them will be just marginally lighter than the
dots themselves. That distance, or rather the number of such distances
in a reference unit, is the optical resolution.

Bear in mind that even a perfect lens won't image an edge as perfect as
you describe - it will always blur due to diffraction. A real lens will
add blur from aberrations, but overcoming diffraction means using as big
an aperture as possible. However, even an infinite aperture will only
resolve (and I mean the Rayleigh version here) about half a wavelength
of light - about 50,000ppi.

So, as you see, reading 4000ppi or 4000dpi on a scanner data sheet and
thinking you will get what you are looking for is just wrong on (at
least) two counts. They are quoting sampling density as resolution, not
optical resolution. It is industry standard, whether we like it or find
it useful or not. But, even if the manufacturers came out and said what
the optical resolution of their scanners were - and the Coolscan 4000 is
pretty close to the equivalent of 4000ppi optical resolution - it still
wouldn't be what you are expecting, and nor would 10,000ppi; perhaps
50,000ppi might be close but there isn't that much information on the
film so don't hold your breath or your wallet to pay for that humungous
lens that it would need! ;-)

>
>>>It cannot nearly reproduce
>>>a good slide in all of its resolution. Sharp, fine text, for
>>>example becomes mushy and, in extreme cases, unreadable.
>
>>OK, you clearly have a problem with focus or dirt. The LS-4000 is
>>particularly fussy about film flatness, so if your film is curved by a
>>couple of millimetres then it will not maintain focus across the entire
>>frame.
>
>Glass frames, but when I take the film out or scan non-glass
>frames, the results are the same. I tested that, of course.
>
OK, worth bearing in mind for the future though - if you get this focus
problem fixed then the next one you will hit is film flatness. :-(

>>Assuming your film is flat, is the scanner set to focus automatically
>>before each scan or preview is made? If you have inadvertently switched
>>this option off in the preferences section then the scanner will just
>>hold the last focus position it had - which could be miles (well, not
>>quite that far) from the correct focus position.
>
>I'm fully aware of when the scanner performs its autofocus
>procedure. I keep finding some slides that are out of focus and
>have to rescan them. Some came out that way because there is no
>contrast in the center, and I have to choose a different focus
>point, but for most the reason is inexplicable, since a
>subsequent scan under identical conditions produces a normally
>sharp picture. No big deal.
>
OK, this is a bit worrying - especially the comment about "contrast in
the center" causing focus problems. The autofocus works on the film
grain, not on the image itself. The only time it should fail is if
there is no film grain at the autofocus position, eg. a completely
transparent emulsion. Even then, minor dust and scratches on the
emulsion surface should be enough to focus on. This suggests that the
optical system is not focussing well enough at its optimum position for
the grain to be resolved very well at all - which confirms your
complaint.

BTW - are you aware than the autofocus point can be moved to any point
in the image? This is particularly useful once you resolve your focus
problem and only have to deal with film flatness - it lets you get the
optimum focus on the part of the frame you think needs it, not just in
the middle.

>>The easiest diagnosis of dirt/dust is to scan a frame edge against a
>>white background on slide film. eg. the black gap between two lighter
>>frames or the edge of the slide mount with light subject matter at the
>>edge of the frame. If you have dirty mirrors or optics then you will
>>notice a smearing of the lighter portions of the image into the black
>>frame. If this is the problem then there is no alternative to having
>>the scanner stripped and cleaned - something you can do yourself if you
>>are confident of working with optical instruments, but otherwise it is
>>better to pay someone who is.
>
>Thanks for this information! It is very useful and interesing!
>
>In my case the scanner seems to be fine and not too dirty.
>
There are a couple of examples of dirty optics scans on the net if you
search google for Coolscan dirty optics including:
http://www.vad1.com/photo/dirty-scanner/
which has links to cleaning these if you find this becomes an issue.

>>[...] Also, measurements show that for near saturated scans,
>>corresponding to shadows on negatives, the photon noise itself is
>>equivalent to just over 8-bits for the CCD. This can be improved by
>>multisampling, to over 10-bits at 16x. You will probably see more gain
>>from multisampling negatives than slides, because the dynamic range of
>>the scanner is very good.
>
>Interesting again. I wasn't sure about how many photons each
>sensor pixel gets, but we're apparently near the limit.

Not what it means. Photon noise is just the random variation on the
arrival of photons at the sensor. This is just like tossing coins - if
you only have one coin then there is just as much chance of getting a
tail (0) as a head (1) - so the noise is the same as the signal. If you
have 100 coins then the chances are the same, but for each time you toss
100 coins the number of heads will vary by less than the 50 heads you
get on average - it should average around 10, giving a signal to noise
of 5. 10,000 coins should give 5,000 heads, but the variation on each
run should average about 100, giving a signal to noise of about 50 and
so on.

So the fact that the photon noise is quite so low is a consequence of
the limitation of the CCD, not an indication that you are close to the
limits of what is achievable. Basically, it means that the CCD can only
detect and store the signal from a limited number of photons before it
saturates - around 100,000. If you could get a better CCD with more
storage capacity in each cell then you could expose for a longer time,
detect more photons and get better signal to noise. Since you are stuck
with whatever Nikon felt gave them the best trade-off between
performance and cost, the best you can do is to simulate a bigger
capacity CCD. That is all that multiscanning does.

>
>>RTFMs - if you don't have copies then download them from the Nikon
>>website. There are two - one for the scanner itself and one for the
>>Nikonscan software.
>
>Did that already. Needed the manual for some information.
>
>>Obtain and install the latest firmware update (v1.10)
>
>v1.10 was already loaded.
>
>>Obtain and install the latest version of NikonScan (v4.02)
>
>Had to do that anyway, because v3 doesn't run on Windows XP.
>
>
>>Your general dissatisfaction with scanners appears to be down to a
>>misunderstanding of what the manufacturers are offering in their
>>specifications.
>
>Let's say an unfulfilled hope that those 4,000 pixels per inch
>should reproduce the information on the slide as well as
>possible. Guess I'd have to buy an 8,000 or 16,000 dpi scanner
>to get a real 4,000 dpi resolution.
>
>But I understand your points and have to accept that the scanner
>manufacturers do it the way we see here.
>
From the discussion above, I hope you now realise that this is not only
unfulfilled, but unrealistic in your terms, but I doubt there is much
more information actually on the film in the first place.

>>What I find more surprising is that you have somehow convinced yourself
>>that so much more information is available on the film to begin with!
>>Try this for comparison: view your scanned edge transition or text on
>>your screen at 100% magnification, so that you can see the softness you
>>are concerned about. Typical displays these days are around 96ppi - so
>>the image size from a full scanned 35mm frame would be around
>>40x60inches. Now, go into a projection room and project your slide at
>>that same size and view it from the same distance as you do the monitor
>>- about 10-12". The original will, of course, look a little sharper
>>but, if your scanner is functioning correctly, it won't be that much
>>sharper and it will surprise you just how little information that the
>>scanner is not capable of lifting off the film.
>
>Here the truth is obvious. I look at a slide that contains some
>small black text on a white background, and I see that the slide
>reproduces that text impressively sharply.
>
>Then I scan the slide at 4,000 dpi, and the text is barely
>readable or not readable any more, even though the number of
>pixels per letter would easily suffice to have it readable. In
>fact, there is a lot of cross-feed from one pixel to the next,
>either because the optics are not sharp enough, could also be
>out of focus, or because there is some cross-feed on the sensor.
>
>But as I wrote, effectively a 4,000 dpi scanner like this is
>unable to reproduce the full sharpness of a slide, and I have to
>accept that grudgingly.
>
Fuji Velvia, for example, goes out to 160lp/mm if the original contrast
is about 1000:1 - but even then, the contrast on the film will only be
about 15% - lower contrast detail will be lost. 160lp/mm is equivalent
to a little over 8000ppi. At a more typical 1.6:1 contrast, Velvia can
only resolve 4000ppi, again reproducing around 15% contrast on the film
(1.15:1). There are marginally higher resolution colour films around,
but not generally available, but this is just the film - the camera lens
and any defocus or shake during exposure will limit the image resolution
further.

So, unless your images often contain very fine detail at a very high
contrast and you shot them with top of the range lenses at their optimum
aperture and used a tripod for everything then it is unlikely there is
much more than 4000ppi on the film itself.

Of course whatever is on the film will be compromised by using a similar
performance scanner and some examples suggest that 5400ppi available
from the Konica Minolta DSE-5400 can pull a bit more off the film than
the 4000ppi Nikons when it is present.
See http://www.xs4all.nl/~bvdwolf/main/foto/scan/se5400/se5...


>I'm still under the impression that this scanner produces
>reasonably sharp pictures at 2,000 dpi. Of course raising the
>resolution always adds some information to the result, but
>raising it to the native 4,000 dpi yields rather little. Egdes,
>for example, don't become any sharper.
>
They may not look like it to you, but if you run some measurements, they
certainly are.


>Let me post an example. Please have a look at
>
>http://www.michna.com/temp/images/india0203_detail_2000...
>http://www.michna.com/temp/images/india0203_detail_4000...
>
Well, just as an instance, in the 4000ppi scan I can easily read
"MYSORE" on the back of the bus and the text below that is almost
legible. It certainly isn't as legible in the 2000ppi scan even after
scaling it back up to the same size, although it is discernible, but the
text below that certainly isn't. In particular, look at the definition
of the R in "MYSORE". Information is present in the 4000ppi scan that
is not there on the 2000ppi scan, though I have to say, it is a lot less
than I have seen on my LS-4000 with similar exercises.

Incidentally, these images show some evidence of the dirty optics I was
referring to earlier - look at how the white of the bus advert has
bloomed out into adjacent areas, such as the black hair of the guy with
the light shirt. Its possible that the original slide is like that
given the type of shot, but I would not be surprised at the scanner
being the source.

Also, what scanner settings did you use for these because both show
rather a lot of posterisation and, given the format, I don't think that
is a compression artefact.

>
>The samples show that the autofocus seems to be imperfect,
>because the higher resolution scan is actually less sharp than
>the 2,000 dpi scan. That's another factor one has to put up
>with.
>
Autofocus is undertaken at the same resolution irrespective of the
resolution of the final scan. If you are getting inconsistent focus it
isn't because you are changing resolution.

>The film is
>Ektachrome 100, by the way. If the camera can do it, why not the
>slide scanner?
>
Well, I bet if you compared the camera to the actual scene (impractical
in all but set tests of course) then you would notice the same
shortfalls on the camera. Any instrument will only make the best
interpretation of the information it has and no instrument is perfect.
Your camera is interpreting the scene and produces what you see on the
film - a lot less than what is in the scene though. However you are
then presenting that to the scanner - it doesn't have the original scene
to work with, so its interpretation of the image will be further
degraded. That will always happen whether your scanner is 4000ppi or
40000ppi.

>Anyway, what you can see is that it serves no purpose to scan at
>4,000 dpi. The pictures do not contain significantly more
>information than 2,000 dpi scans.
>
I disagree, and your examples have not changed my view.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 16, 2005 3:26:15 PM

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

In article <dgdv02$koh$1@nnrp.gol.com>, David J. Littleboy
<davidjl@gol.com> writes
>
>*: The US$3500 question I'm agonizing with this month is whether 12MP of 5D
>pixels are (a) really "worth more" than 16MP (645) of these fairly nice 2200
>ppi pixels (I'm pretty sure 12MP wins hands down here), and (b) whether I
>will be _un_happy enough with those 12MP pixels printed at 224 ppi (13x19)
>compared to 28MP (6x7) of those fairly nice pixels printed at 312 ppi (also
>13x19). This (b) part is hard.
>
Whilst not agonizing (other things have been causing that much more
literally recently) I am going through a similar debate myself, having
rejected the digital camera route for anything more than toys thus far
due to combinations of cost and performance. The 5D is likely to break
the rule I had previously set myself of waiting till the 1Ds
became affordable within my priorities.

I am fairly confident that 5D output printed at 13x19" will be perfectly
acceptable even though the source resolution will be around 220ppi - the
sample images available at 100 & 200ASA look so noise free that
resampling sensibly to the printer native resolution will pretty much
artefact free. 220ppi is only just below the resolution of an unaided
human eye, so nobody will notice the pixel deficiency from the sensor
unless comparing it directly to something else with aided vision. It is
more a question of whether optics are really up to that sort of
enlargement - 14x scaling (excluding crops) is really asking a lot.

>If the flipping 5D had 16.7MP (250 ppi at
>13x19) I wouldn't be worrying this. Aaaaaaaaaaaarg.

Yes you would - you'd just be at the next layer of the onion and
worrying about the optical scaling, wishing the 5D was a 645 format
camera instead of 35mm.

The question I have to ask myself is more along the lines of does the
quality of the 5D justify investing 7-10k of UKP on a complete new set
of optics and accessories. The answer is probably yes, but its a hard
one to implement.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 16, 2005 8:20:40 PM

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

On Fri, 16 Sep 2005 00:43:38 +0200, philip@pch.home.cs.vu.nl
(Philip Homburg) wrote:

><http://misc.hq.phicoh.net/edge/Image2a.tif&gt;
>is a crop of a scan of a razor blade.

Philip,

good example! Instead of the ideal one grey pixel between the
black and white areas it has six. In other words, the scan is
very decidedly unsharp. You can reduce the resolution by a
factor of 2, 4, or even 6 without losing much information.
That's also what I observe.

The scanner is incomparably worse than the camera and the film I
used to take photos.

I guess that's just how it is. I don't quite understand why a
scanner of a quality comparable to a camera has to be many times
more expensive than a camera, but I can't change it. Perhaps it
is because many more cameras are made than film scanners.

Hans-Georg

--
No mail, please.
Anonymous
September 16, 2005 8:20:40 PM

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

On Fri, 16 Sep 2005 05:42:24 +0100, Kennedy McEwen
<rkm@nospam.demon.co.uk> wrote:

>It is worth noting that this interpretation of resolution, whilst not
>unique to yourself, is incorrect. Two forms of resolution take place in
>scanners - sampling resolution (which I prefer to call sampling density
>to avoid confusion) and optical resolution. Sampling resolution or
>density is the headline number that the manufacturers hit you with and
>is basically the number of pixels that the scanner samples per inch. It
>doesn't say anything about the actual performance of the scanner or how
>distinct any pixel is from adjacent pixels. That comes down to optical
>resolution and, as I am sure you have guessed, manufacturers are less
>than vociferous in making customers, let alone potential customers,
>aware of that. There are good reasons for this - people are stupid and
>will buy a scanner from a manufacturer that claims 4,000ppi resolution
>than one who offers only 1500cy/in resolution.

Kennedy,

yes, I'm fully aware of this. That's why I reduced my scan
resolution from 4,000 ppi first to 2,400 ppi, then to 2,000 ppi.
Of course I lose some information that way, I'm fully aware of
that too, but not enough to warrant the much larger files.

>The autofocus works on the film
>grain, not on the image itself. The only time it should fail is if
>there is no film grain at the autofocus position, eg. a completely
>transparent emulsion. Even then, minor dust and scratches on the
>emulsion surface should be enough to focus on. This suggests that the
>optical system is not focussing well enough at its optimum position for
>the grain to be resolved very well at all - which confirms your
>complaint.

Interesting! I guess I will have to have the scanner cleaned and
checked. However, perhaps the errors happened because the
scanner focussed on the glass surface, rather than on the film.
I use GePe anti-Newton glass frames.

>BTW - are you aware than the autofocus point can be moved to any point
>in the image? This is particularly useful once you resolve your focus
>problem and only have to deal with film flatness - it lets you get the
>optimum focus on the part of the frame you think needs it, not just in
>the middle.

Yes, I used that function in a few cases. Do you happen to know
under which circumstances the scanner puts the autofocus point
back in the center? I'd like it back when I scan the next
picture, but I couldn't find out, so I always moved it back by
hand, which may be unnecessary.

>Not what it means. Photon noise is just the random variation on the
>arrival of photons at the sensor. [...]

>So the fact that the photon noise is quite so low is a consequence of
>the limitation of the CCD, not an indication that you are close to the
>limits of what is achievable. Basically, it means that the CCD can only
>detect and store the signal from a limited number of photons before it
>saturates - around 100,000. If you could get a better CCD with more
>storage capacity in each cell then you could expose for a longer time,
>detect more photons and get better signal to noise. Since you are stuck
>with whatever Nikon felt gave them the best trade-off between
>performance and cost, the best you can do is to simulate a bigger
>capacity CCD. That is all that multiscanning does.

Thanks for the very good explanation! I'm learning.

> From the discussion above, I hope you now realise that this is not only
>unfulfilled, but unrealistic in your terms, but I doubt there is much
>more information actually on the film in the first place.

Oh, but there is! When I look at the photo, from which I took
the two samples, through a magnifying glass, the text on the bus
is absolutely black and sharp, incomparably better than the
light grey fuzzy stuff in the scans. I can only surmise that the
optical quality of the scanner optics is way below that of the
camera lens through which I took the photo.

>Fuji Velvia, for example, goes out to 160lp/mm if the original contrast
>is about 1000:1 - but even then, the contrast on the film will only be
>about 15% - lower contrast detail will be lost. 160lp/mm is equivalent
>to a little over 8000ppi. At a more typical 1.6:1 contrast, Velvia can
>only resolve 4000ppi, again reproducing around 15% contrast on the film
>(1.15:1). There are marginally higher resolution colour films around,
>but not generally available, but this is just the film - the camera lens
>and any defocus or shake during exposure will limit the image resolution
>further.
>
>So, unless your images often contain very fine detail at a very high
>contrast and you shot them with top of the range lenses at their optimum
>aperture and used a tripod for everything then it is unlikely there is
>much more than 4000ppi on the film itself.

Wish I could send you the original slide! This was Ektachrome
100 shot through a good Canon lens. Too bad I have no way of
scanning through a microscope to show you what's actually on the
slide.

But assuming the film contains good 4,000 ppi information, but
the scanner's optics are obviously way below that, the
phenomenon is already explained.

>In article <l33ji118l0n73b8379v1jso381hnna5fo1@4ax.com>, Hans-Georg
>Michna <hans-georgNoEmailPlease@michna.com> writes

>>I'm still under the impression that this scanner produces
>>reasonably sharp pictures at 2,000 dpi. Of course raising the
>>resolution always adds some information to the result, but
>>raising it to the native 4,000 dpi yields rather little. Egdes,
>>for example, don't become any sharper.

>They may not look like it to you, but if you run some measurements, they
>certainly are.

Of course the 4,000 ppi scans contain more information than the
2,000 ppi scans, but the difference appears small to me,
particularly when compared to the roughly 4 times larger file
size.

>>Let me post an example. Please have a look at
>>
>>http://www.michna.com/temp/images/india0203_detail_2000...
>>http://www.michna.com/temp/images/india0203_detail_4000...

>Also, what scanner settings did you use for these because both show
>rather a lot of posterisation and, given the format, I don't think that
>is a compression artefact.

The 2,000 ppi scan was stored in JPEG format at the highest
quality setting. The 4,000 ppi scan was never compressed, only
converted from TIFF to PNG, so it does not contain any
compression artefacts. I converted both to PNG to avoid losing
quality again after cropping.

I guess that there are much better scanners that can easily
resolve 4,000 ppi to the pixel. I'd guess they'd be advertised
as 8,000 ppi at least, probably even 16,000 ppi. Do you happen
to know such scanners? What do they cost?

Hans-Georg

--
No mail, please.
Anonymous
September 16, 2005 9:15:55 PM

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

"Kennedy McEwen" <rkm@nospam.demon.co.uk> wrote:
>>
> BTW - are you aware than the autofocus point can be moved to any point in
> the image? This is particularly useful once you resolve your focus
> problem and only have to deal with film flatness - it lets you get the
> optimum focus on the part of the frame you think needs it, not just in the
> middle.

It's even better than that. You can use the AF system to measure the
position of the film at enough points on the film to determine the range of
distances, and then set the focus manually to the center of that range and
get everything on the frame in focus.

>>Anyway, what you can see is that it serves no purpose to scan at
>>4,000 dpi. The pictures do not contain significantly more
>>information than 2,000 dpi scans.
>>
> I disagree, and your examples have not changed my view.

The salient term in there is "significant", and we may have different
definitions. I _think_ that scanning at 4000 ppi, applying noise reduction
and a tad of sharpening, and then downsampling to 2200 ppi or so will
produce better pixels* than just scanning at 2000 ppi. I think. But in
general, most scans can be bicubic downsampled to 1/2 the scanning density
and then bicubic upsampled to the original scanning density without
_significant_ loss of information.

*: The US$3500 question I'm agonizing with this month is whether 12MP of 5D
pixels are (a) really "worth more" than 16MP (645) of these fairly nice 2200
ppi pixels (I'm pretty sure 12MP wins hands down here), and (b) whether I
will be _un_happy enough with those 12MP pixels printed at 224 ppi (13x19)
compared to 28MP (6x7) of those fairly nice pixels printed at 312 ppi (also
13x19). This (b) part is hard. If the flipping 5D had 16.7MP (250 ppi at
13x19) I wouldn't be worrying this. Aaaaaaaaaaaarg.

David J. Littleboy
davidjl@stream.of.conciousness.com
Tokyo, Japan
Anonymous
September 16, 2005 9:31:37 PM

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

In article <0cili1lj34g5fa06ieeurkfsobruim7vbh@4ax.com>,
Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> wrote:
>On Fri, 16 Sep 2005 00:43:38 +0200, philip@pch.home.cs.vu.nl
>(Philip Homburg) wrote:
>good example! Instead of the ideal one grey pixel between the
>black and white areas it has six. In other words, the scan is
>very decidedly unsharp. You can reduce the resolution by a
>factor of 2, 4, or even 6 without losing much information.
>That's also what I observe.

Check out Image3a.tif and Image1a.tif as well. I accidentally left ICE
on (which of course doesn't work with a razer blade).

Image1a suggests that manually focussing the scanner is not really an
option.

>The scanner is incomparably worse than the camera and the film I
>used to take photos.

No, the scanner is good enough for color film.


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency
Anonymous
September 17, 2005 12:03:40 AM

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

"Kennedy McEwen" <rkm@nospam.demon.co.uk> wrote:
> David J. Littleboy <davidjl@gol.com> writes
>>
>>*: The US$3500 question I'm agonizing with this month is whether 12MP of
>>5D
>>pixels are (a) really "worth more" than 16MP (645) of these fairly nice
>>2200
>>ppi pixels (I'm pretty sure 12MP wins hands down here), and (b) whether I
>>will be _un_happy enough with those 12MP pixels printed at 224 ppi (13x19)
>>compared to 28MP (6x7) of those fairly nice pixels printed at 312 ppi
>>(also
>>13x19). This (b) part is hard.
>>
> Whilst not agonizing (other things have been causing that much more
> literally recently) I am going through a similar debate myself, having
> rejected the digital camera route for anything more than toys thus far due
> to combinations of cost and performance.

We're more on the same page than I expected<g>. (Although I purchased a 300D
for family snaps and low-light work.)

> I am fairly confident that 5D output printed at 13x19" will be perfectly
> acceptable even though the source resolution will be around 220ppi - the
> sample images available at 100 & 200ASA look so noise free that resampling
> sensibly to the printer native resolution will pretty much artefact free.
> 220ppi is only just below the resolution of an unaided human eye, so
> nobody will notice the pixel deficiency from the sensor unless comparing
> it directly to something else with aided vision.

I hope you're right...

> It is more a question of whether optics are really up to that sort of
> enlargement - 14x scaling (excluding crops) is really asking a lot.

Here, though, I'm more sanguine. The resolution (not the "limiting
resolution" but the "apparent resolution when test charts are viewed at 100%
on the screen") is about 40 lp/mm, and that's not too painful. The 17-40 is
going to be a tad soft in the corners at 17, but I'm expecting it to be fine
in the 20 to 24mm range. And any prime 35mm or longer will be fine.

>>If the flipping 5D had 16.7MP (250 ppi at
>>13x19) I wouldn't be worrying this. Aaaaaaaaaaaarg.
>
> Yes you would - you'd just be at the next layer of the onion and worrying
> about the optical scaling, wishing the 5D was a 645 format camera instead
> of 35mm.

Well, actually, no. I really don't need anything more than 13x19, so 16.7MP
would be perfect. (But lens infelicities would raise their ugly head more
than with 12MP.)

> The question I have to ask myself is more along the lines of does the
> quality of the 5D justify investing 7-10k of UKP on a complete new set of
> optics and accessories. The answer is probably yes, but its a hard one to
> implement.

I planned ahead. When I bought my 300D last year, I bought the lenses I'd
need for the 5D. (Well, all except the 85/1.8: the Tamron 28-75/2.8 will
have to do in the short term, but my wife wants the 300D, and that's the
lens she'll want on it.)

David J. Littleboy
Tokyo, Japan
Anonymous
September 18, 2005 7:28:15 PM

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

I don't think you have to worry about the 5D at 13"x19". I have prints
made from the 20D. 12"x18" no sweat. Even 20"x30" are impressive. I
realize the ppi number is something like 115 here. But practically (and
I am sure there is some image dependance) the end result is what
counts. (I upsample to 300ppi then USM) I think the 20D can create
images in many ways superior to 35mm film. The 5D should be quite
impressive!!


David J. Littleboy wrote:
> "Kennedy McEwen" <rkm@nospam.demon.co.uk> wrote:
> > David J. Littleboy <davidjl@gol.com> writes
> >>
> >>*: The US$3500 question I'm agonizing with this month is whether 12MP of
> >>5D
> >>pixels are (a) really "worth more" than 16MP (645) of these fairly nice
> >>2200
> >>ppi pixels (I'm pretty sure 12MP wins hands down here), and (b) whether I
> >>will be _un_happy enough with those 12MP pixels printed at 224 ppi (13x19)
> >>compared to 28MP (6x7) of those fairly nice pixels printed at 312 ppi
> >>(also
> >>13x19). This (b) part is hard.
> >>
> > Whilst not agonizing (other things have been causing that much more
> > literally recently) I am going through a similar debate myself, having
> > rejected the digital camera route for anything more than toys thus far due
> > to combinations of cost and performance.
>
> We're more on the same page than I expected<g>. (Although I purchased a 300D
> for family snaps and low-light work.)
>
> > I am fairly confident that 5D output printed at 13x19" will be perfectly
> > acceptable even though the source resolution will be around 220ppi - the
> > sample images available at 100 & 200ASA look so noise free that resampling
> > sensibly to the printer native resolution will pretty much artefact free.
> > 220ppi is only just below the resolution of an unaided human eye, so
> > nobody will notice the pixel deficiency from the sensor unless comparing
> > it directly to something else with aided vision.
>
> I hope you're right...
>
> > It is more a question of whether optics are really up to that sort of
> > enlargement - 14x scaling (excluding crops) is really asking a lot.
>
> Here, though, I'm more sanguine. The resolution (not the "limiting
> resolution" but the "apparent resolution when test charts are viewed at 100%
> on the screen") is about 40 lp/mm, and that's not too painful. The 17-40 is
> going to be a tad soft in the corners at 17, but I'm expecting it to be fine
> in the 20 to 24mm range. And any prime 35mm or longer will be fine.
>
> >>If the flipping 5D had 16.7MP (250 ppi at
> >>13x19) I wouldn't be worrying this. Aaaaaaaaaaaarg.
> >
> > Yes you would - you'd just be at the next layer of the onion and worrying
> > about the optical scaling, wishing the 5D was a 645 format camera instead
> > of 35mm.
>
> Well, actually, no. I really don't need anything more than 13x19, so 16.7MP
> would be perfect. (But lens infelicities would raise their ugly head more
> than with 12MP.)
>
> > The question I have to ask myself is more along the lines of does the
> > quality of the 5D justify investing 7-10k of UKP on a complete new set of
> > optics and accessories. The answer is probably yes, but its a hard one to
> > implement.
>
> I planned ahead. When I bought my 300D last year, I bought the lenses I'd
> need for the 5D. (Well, all except the 85/1.8: the Tamron 28-75/2.8 will
> have to do in the short term, but my wife wants the 300D, and that's the
> lens she'll want on it.)
>
> David J. Littleboy
> Tokyo, Japan
Anonymous
September 19, 2005 2:05:15 PM

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

On Fri, 16 Sep 2005 17:31:37 +0200, philip@pch.home.cs.vu.nl
(Philip Homburg) wrote:

>Check out Image3a.tif and Image1a.tif as well. I accidentally left ICE
>on (which of course doesn't work with a razer blade).

Philip,

http://misc.hq.phicoh.net/edge/Image3a.tif is better, but still
has around 4 grey (or even green) pixels between the black and
the white areas, rather than the perfect 1 grey pixel.

In other words, you have to reduce the resolution by a factor of
2 to 4 to achieve a really sharp picture.

But I think we've discussed this exhaustively now. The scanner
optics aren't good enough to fill the sensor pixels with a
perfect picture.

Hans-Georg

--
No mail, please.
Anonymous
September 19, 2005 2:15:17 PM

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

In article <t0ssi11akgvjhtm4jhk7evm92i3k666tep@4ax.com>,
Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> wrote:
>But I think we've discussed this exhaustively now. The scanner
>optics aren't good enough to fill the sensor pixels with a
>perfect picture.

I understand that you are willing to ignore the very sharp transition in
the other image because it doesn't help your case. Well, it is not my problem.
Happy scanning.


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency
Anonymous
September 19, 2005 5:38:54 PM

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

On Mon, 19 Sep 2005 10:15:17 +0200, philip@pch.home.cs.vu.nl
(Philip Homburg) wrote:

>In article <t0ssi11akgvjhtm4jhk7evm92i3k666tep@4ax.com>,
>Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> wrote:

>>But I think we've discussed this exhaustively now. The scanner
>>optics aren't good enough to fill the sensor pixels with a
>>perfect picture.

>I understand that you are willing to ignore the very sharp transition in
>the other image because it doesn't help your case. Well, it is not my problem.
>Happy scanning.

Philip,

do you mean the upper edge of the dark area in picture
http://misc.hq.phicoh.net/edge/Image1a.tif ? That is indeed
satisfactory. I wasn't sure how this was done and hadn't looked
at that picture again.

How come some edges are sharp and others aren't?

I happened to stumble over one of my slides that was cropped by
means of a paper frame in the slide. I scanned the edges, and
they showed relatively good results, essentially two grey pixel
rows plus some smaller effect on the adjacent rows.

This was done with ICE enabled. I don't think ICE generally
reduces sharpness.

Hans-Georg

--
No mail, please.
Anonymous
September 19, 2005 7:09:48 PM

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

In article <lq7ti1thpk2reo0ber91fch7anoq1eisom@4ax.com>,
Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> wrote:
>do you mean the upper edge of the dark area in picture
>http://misc.hq.phicoh.net/edge/Image1a.tif ? That is indeed
>satisfactory. I wasn't sure how this was done and hadn't looked
>at that picture again.
>
>How come some edges are sharp and others aren't?

The problem with the razor blade is that autofocus doesn't work with
the LS-4000. In theory a razor blade is good because it is sharp, but it is
possible that in practice you want the edge of a film strip.

Without autofocus, it looks like it is almost impossible to get good focus
on an LS-4000.

>This was done with ICE enabled. I don't think ICE generally
>reduces sharpness.

ICE does have a small effect on sharpness.


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency
Anonymous
September 20, 2005 4:06:36 AM

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

In article <t0ssi11akgvjhtm4jhk7evm92i3k666tep@4ax.com>, Hans-Georg
Michna <hans-georgNoEmailPlease@michna.com> writes
>On Fri, 16 Sep 2005 17:31:37 +0200, philip@pch.home.cs.vu.nl
>(Philip Homburg) wrote:
>
>>Check out Image3a.tif and Image1a.tif as well. I accidentally left ICE
>>on (which of course doesn't work with a razer blade).
>
>Philip,
>
>http://misc.hq.phicoh.net/edge/Image3a.tif is better, but still
>has around 4 grey (or even green) pixels between the black and
>the white areas, rather than the perfect 1 grey pixel.
>
Hans-George - 1 grey pixel in the transition between black and white is
*NOT* ideal, nor is it desirable. For an explanation of this, see my
response to your question of how many grey pixels are acceptable in the
similarly titled thread you have started in comp.periphs.scanners.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 20, 2005 4:17:01 AM

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

In article <1127082495.780650.230130@g47g2000cwa.googlegroups.com>,
"winhag@yahoo.com" <winhag@yahoo.com> writes
>I don't think you have to worry about the 5D at 13"x19". I have prints
>made from the 20D. 12"x18" no sweat. Even 20"x30" are impressive. I
>realize the ppi number is something like 115 here. But practically (and
>I am sure there is some image dependance) the end result is what
>counts. (I upsample to 300ppi then USM) I think the 20D can create
>images in many ways superior to 35mm film.

I have seen some 20D images at 13x19" and they are less than ideal -
certainly less sharp than David will be getting from 645 film and
definitely less than his 6x7cm shots. I am sure it is a matter of
acceptability thresholds, experience and expectations as to whether you
find the results impressive or not. As I mentioned, x14 enlargement is
pushing it for 35mm optics - x22 from these 1.6x multipliers is beyond
the pale for close inspection.

However, since David already has a similar frame and pixel count dSLR to
the Canon 20D in his Canon 350D, I don't think he would be agonising
over the question of whther the 5D would be good enough for his need if
the results from either 20D or 350D were already good enough.

>The 5D should be quite
>impressive!!
>
That's what I am hoping for, but pixel count isn't the only issue at
these print sizes.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 22, 2005 6:36:18 AM

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

Kennedy McEwen <rkm@nospam.demon.co.uk> writes:

> In article <1127082495.780650.230130@g47g2000cwa.googlegroups.com>,

> "winhag@yahoo.com" <winhag@yahoo.com> writes

>>I don't think you have to worry about the 5D at 13"x19". I have
>>prints made from the 20D. 12"x18" no sweat. Even 20"x30" are
>>impressive. I realize the ppi number is something like 115 here. But
>>practically (and I am sure there is some image dependance) the end
>>result is what counts. (I upsample to 300ppi then USM) I think the
>>20D can create images in many ways superior to 35mm film.

> I have seen some 20D images at 13x19" and they are less than ideal -
> certainly less sharp than David will be getting from 645 film and
> definitely less than his 6x7cm shots. I am sure it is a matter of
> acceptability thresholds, experience and expectations as to whether
> you find the results impressive or not. As I mentioned, x14
> enlargement is pushing it for 35mm optics - x22 from these 1.6x
> multipliers is beyond the pale for close inspection.

I have seen a 20x24 from a D30, yes, you read that right, that was
acceptable. Wedding semi-formal, sepia printed, with squared off
`pixelation'. Worked well... The sepia was the key I think.

--
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
September 22, 2005 6:36:19 AM

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

On Thu, 22 Sep 2005 02:36:18 +0800, prep@prep.synonet.com wrote:

>I have seen a 20x24 from a D30, yes, you read that right, that was
>acceptable. Wedding semi-formal, sepia printed, with squared off
>`pixelation'. [...]

Paul,

why not upscale it smoothly, using suitable software? pxl
SmartScale comes to mind, or Genuine Fractals, or at least
Qimage.

Hans-Georg

--
No mail, please.
Anonymous
September 22, 2005 11:58:11 PM

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

If you are concerned about the 35mm optics, You could always get an
adapter and put medium format glass on your 5D.
Regarding your other comments ('20D images at 13"x19" being less than
ideal), I am coming from the 35mm film world. From what I have seen,
20D @ 13x19 will generally beat 35mm film at 13x19 from a perception
point of view, and I don't want to think of how grainy/fuzzy the 35mm
film shots would look at 20"x30" (although to be honest I never had the
guts to try it :)  ).



Kennedy McEwen wrote:
> In article <1127082495.780650.230130@g47g2000cwa.googlegroups.com>,
> "winhag@yahoo.com" <winhag@yahoo.com> writes
> >I don't think you have to worry about the 5D at 13"x19". I have prints
> >made from the 20D. 12"x18" no sweat. Even 20"x30" are impressive. I
> >realize the ppi number is something like 115 here. But practically (and
> >I am sure there is some image dependance) the end result is what
> >counts. (I upsample to 300ppi then USM) I think the 20D can create
> >images in many ways superior to 35mm film.
>
> I have seen some 20D images at 13x19" and they are less than ideal -
> certainly less sharp than David will be getting from 645 film and
> definitely less than his 6x7cm shots. I am sure it is a matter of
> acceptability thresholds, experience and expectations as to whether you
> find the results impressive or not. As I mentioned, x14 enlargement is
> pushing it for 35mm optics - x22 from these 1.6x multipliers is beyond
> the pale for close inspection.
>
> However, since David already has a similar frame and pixel count dSLR to
> the Canon 20D in his Canon 350D, I don't think he would be agonising
> over the question of whther the 5D would be good enough for his need if
> the results from either 20D or 350D were already good enough.
>
> >The 5D should be quite
> >impressive!!
> >
> That's what I am hoping for, but pixel count isn't the only issue at
> these print sizes.
> --
> Kennedy
> Yes, Socrates himself is particularly missed;
> A lovely little thinker, but a bugger when he's pissed.
> Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 23, 2005 12:08:07 PM

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

David,

I did as you suggested (i.e. printing out the image at 300ppi). There
is a difference but not a heck of alot! I even looked with a magnifying
glass. Clearly, the '12mp' image has more info and detail but I don't
agree that at sizes like 13"x19" an 8MP cam cannot produce a
perceptully 'sharp' image. It may just be that you have very high
expectations in this regard. It is an interesting comparison.
Anonymous
September 23, 2005 12:12:42 PM

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

My experience has been that color 35mm film scanned at 4000dpi many
times has issues even at 12"x18". Alot of times it depends on the
subject. For example portrait vs. landscape. There typically is alot
more 'expectation of detail' when a landscape is greatly enlarged. Do
you have any examples (even snippets) of the 20"x30" you can show?
Anonymous
September 23, 2005 4:12:41 PM

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

<winhag@yahoo.com> wrote in message
news:1127444291.144466.167650@o13g2000cwo.googlegroups.com...
> If you are concerned about the 35mm optics, You could always get an
> adapter and put medium format glass on your 5D.
> Regarding your other comments ('20D images at 13"x19" being less than
> ideal), I am coming from the 35mm film world. From what I have seen,
> 20D @ 13x19 will generally beat 35mm film at 13x19 from a perception
> point of view,

Print this guy out at 300 ppi to see what 12MP would look like at 13x19
compared to 6 and 8MP.

http://www.pbase.com/davidjl/image/49661213/original

Explanation at:
http://forums.dpreview.com/forums/read.asp?forum=1032&m...

David J. Littleboy
Tokyo, Japan
Anonymous
September 23, 2005 5:04:47 PM

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

winhag@yahoo.com wrote:

> Regarding your other comments ('20D images at 13"x19" being less than
> ideal), I am coming from the 35mm film world. From what I have seen,
> 20D @ 13x19 will generally beat 35mm film at 13x19 from a perception
> point of view, and I don't want to think of how grainy/fuzzy the 35mm
> film shots would look at 20"x30" (although to be honest I never had the
> guts to try it :)  ).

20x30 from asa 100-200 films look very good. try mystic color labs

>
>>Kennedy
>>Yes, Socrates himself is particularly missed;
>>A lovely little thinker, but a bugger when he's pissed.
>>Python Philosophers (replace 'nospam' with 'kennedym' when replying)
>
>
Anonymous
September 24, 2005 11:03:12 AM

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

I apologize for not reading the full thread. I would then pretty much
agree with your points. However, my guess
is that the 5D will not disappoint at 13"x19" regardless of what format
it is compared to. But of course this
is speculation on my part based on experience with 35mm film, medium
format film, and the 20D.
Anonymous
September 24, 2005 11:38:59 AM

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

"winhag@yahoo.com" <winhag@yahoo.com> writes:
>If you are concerned about the 35mm optics, You could always get an
>adapter and put medium format glass on your 5D.

That's generally a poor idea. Medium format glass will generally have
*lower* resolution than 35 mm camera glass, measured in lp/mm.

Medium format cameras take higher resolution *pictures* because they can
resolve more line pairs per picture width - but that's mostly because
the image is larger. Resolution per mm usually gets worse as you move
to longer focal length lenses designed for larger formats.

Dave
Anonymous
September 24, 2005 2:23:57 PM

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

In article <P3TYe.20321$265.10315@trndny07>, bob crownfield
<crownfield@verizon.net> writes
>winhag@yahoo.com wrote:
>
>> Regarding your other comments ('20D images at 13"x19" being less than
>> ideal), I am coming from the 35mm film world. From what I have seen,
>> 20D @ 13x19 will generally beat 35mm film at 13x19 from a perception
>> point of view, and I don't want to think of how grainy/fuzzy the 35mm
>> film shots would look at 20"x30" (although to be honest I never had the
>> guts to try it :)  ).
>
>20x30 from asa 100-200 films look very good. try mystic color labs
>
Not compared to the same size results from mid and large format films
they don't - and please be more careful on your quoting: although you
left my sig attached to your snipped quote, I did not write a single
word of what you quoted!
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 24, 2005 2:40:20 PM

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

In article <1127444291.144466.167650@o13g2000cwo.googlegroups.com>,
"winhag@yahoo.com" <winhag@yahoo.com> writes
>If you are concerned about the 35mm optics, You could always get an
>adapter and put medium format glass on your 5D.

And how is that going to help?

The issue isn't the fact that the optics are designed for 35mm, it is
that the format is 35mm or less and requires a more substantial
enlargement, magnifying the limitations of the optic when printed at
large scale.

In terms of performance at the focal plane, many mid and large format
optics are actually inferior to 35mm optics but, because the enlargement
required for any particular final image size is less, the end result
from those inferior lenses is still better, particularly in the corners.
A 20D image printed at 13x19 requires x22 enlargement, a 35mm frame x14,
but a 6x7cm frame only x7 - it is the enlargement that makes the biggest
difference in image quality and why, despite having smaller (6.4um
compared to 8.2um ie. higher resolution at the focal plane) pixels the
images from the 20D will be noticeably inferior to those from the 5D
shot with the same optic, in just the same way as 35mm images are better
than APS images and mid format is better than 35mm.

>Regarding your other comments ('20D images at 13"x19" being less than
>ideal), I am coming from the 35mm film world. From what I have seen,
>20D @ 13x19 will generally beat 35mm film at 13x19 from a perception
>point of view, and I don't want to think of how grainy/fuzzy the 35mm
>film shots would look at 20"x30" (although to be honest I never had the
>guts to try it :)  ).

You seem to have missed the point. David isn't comparing these cameras
to 35mm film - he is comparing them to 645 and 6x7 film. That is what
he is already using and it is how the results will compare with those
formats that he is concerned about. Read his original statement about
what he was agonising over. My comments were intended to point out that
although the sensor itself will be better than 35mm film, the lens won't
and the effect of that lens when printed at 13x19" will be inferior to
the effect of a mid format lens when enlarged to the same print size. If
you have never used mid and large format cameras then you will be
surprised by how much effect that actually has on the result.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
Anonymous
September 24, 2005 8:52:44 PM

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

"Dave Martindale" <davem@cs.ubc.ca> wrote:
> "winhag@yahoo.com" <winhag@yahoo.com> writes:
>>If you are concerned about the 35mm optics, You could always get an
>>adapter and put medium format glass on your 5D.
>
> That's generally a poor idea. Medium format glass will generally have
> *lower* resolution than 35 mm camera glass, measured in lp/mm.
>
> Medium format cameras take higher resolution *pictures* because they can
> resolve more line pairs per picture width - but that's mostly because
> the image is larger. Resolution per mm usually gets worse as you move
> to longer focal length lenses designed for larger formats.

Pretty much all of the 'name' lenses reported at the site below resolve a
lot more than the 40 lp/mm practical limiting resolution of the 5D sensor.
Of course, you need decent contrast at that resolution, so you should
probably see the 60 lp/mm Nyquist frequency for the sensor as the minimum
acceptable resolution.

http://www.hevanet.com/cperez/MF_testing.html

David J. Littleboy
Tokyo, Japan
Anonymous
September 24, 2005 10:16:12 PM

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

"David J. Littleboy" <davidjl@gol.com> writes:

>> Medium format cameras take higher resolution *pictures* because they can
>> resolve more line pairs per picture width - but that's mostly because
>> the image is larger. Resolution per mm usually gets worse as you move
>> to longer focal length lenses designed for larger formats.

>Pretty much all of the 'name' lenses reported at the site below resolve a
>lot more than the 40 lp/mm practical limiting resolution of the 5D sensor.
>Of course, you need decent contrast at that resolution, so you should
>probably see the 60 lp/mm Nyquist frequency for the sensor as the minimum
>acceptable resolution.

Sure, but any decent 35 mm camera lens will resolve that too.

My point was that, in general, it's not a good idea to switch to a lens
intended for a larger format to try to get more resolution. Those
lenses are designed for good sharpness and covering power *for the
format*, and that format achieves higher resolution than 35 mm
principally by having more image area than 35. But if you use a lens
designed for 4x5 (or 8x10) on a 35 camera, you aren't using the large
covering power of the lens, and you'll end up enlarging the image you
do capture by much more than a 4x5 plate. The lens and image format
are badly mismatched.

Even with the mythical aberration-free lens, resolution goes down with
aperture due to diffraction, and larger-format lenses tend to have
smaller maximum apertures.

As a general trend, lenses intended to cover larger formats resolve
more line pairs per picture height, but fewer line pairs per mm. Of
course, if you're comparing a $1000 single focal length medium format
view camera lens to a $200 zoom intended for 35mm, this isn't going to
be true. But try comparing to a good macro lens for 35 mm.

Dave
Anonymous
September 25, 2005 10:39:51 PM

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

I have been poking around on the web regarding tools like G. Fractals
and SmartScale. From what I have seen, they are expensive and
questionable in their value. Both G. Fractals and pxl SmartScale are
about $200. Do they really work better
than bicubic upsample followed by Unsharp Masking?
Anonymous
September 26, 2005 12:58:15 PM

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

On 25 Sep 2005 18:39:51 -0700, "winhag@yahoo.com"
<winhag@yahoo.com> wrote:

>I have been poking around on the web regarding tools like G. Fractals
>and SmartScale. From what I have seen, they are expensive and
>questionable in their value. Both G. Fractals and pxl SmartScale are
>about $200. Do they really work better
>than bicubic upsample followed by Unsharp Masking?

Certainly pxl SmartScale is hard to beat when it comes to
turning an unsharp high-contrast edge into a perfectly sharp
one. Whether that's desirable is an interesting question.

I would say, if the original edge (the one in nature) was sharp,
then the picture gains by reproducing it correctly. If not, then
not. (:-)

My Canon printer driver has a similar function. Enabling that
made an aerial photograph much better, because the white houses
on the dark ground came out perfectly sharp. That was a definite
improvement.

Hans-Georg

--
No mail, please.
!