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New lens technology?

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Anonymous
May 23, 2005 4:36:26 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

http://www.canada.com/national/nationalpost/news/story....


--
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-- e-meil: Remove FreeLunch.

More about : lens technology

Anonymous
May 23, 2005 6:46:29 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"Joseph Meehan" <sligojoe_Spamno@hotmail.com> writes:

> Alan Browne wrote:
>> http://www.canada.com/national/nationalpost/news/story....
>
> "Galstian said the lens would work in cellphone cameras that take
> notoriously poor quality images."
>
> Well after that bit of wisdom, I ignored the rest of the story. The
> best lens in the business is not going to help the pixel poor cell phone
> image.

My cell phone takes images which are *far* poorer than the pixel
limitations alone can excuse. Compare the first and second photos at
<http://www.dd-b.net/dd-b/SnapshotAlbum/data/2005/05310-...;;
the first one was taken with a Fuji S2, and resized to 700xwhatever.
The second was taken with my Nokia phone, and is the full original
size (640x480). There are lots of problems with that photo beyond
being limited to that small size!
--
David Dyer-Bennet, <mailto:D d-b@dd-b.net>, <http://www.dd-b.net/dd-b/&gt;
RKBA: <http://noguns-nomoney.com/&gt; <http://www.dd-b.net/carry/&gt;
Pics: <http://dd-b.lighthunters.net/&gt; <http://www.dd-b.net/dd-b/SnapshotAlbum/&gt;
Dragaera/Steven Brust: <http://dragaera.info/&gt;
Anonymous
May 23, 2005 7:51:17 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

David Dyer-Bennet wrote:
> My cell phone takes images which are *far* poorer than the pixel
> limitations alone can excuse. Compare the first and second photos at
> <http://www.dd-b.net/dd-b/SnapshotAlbum/data/2005/05310-...;;
> the first one was taken with a Fuji S2, and resized to 700xwhatever.
> The second was taken with my Nokia phone, and is the full original
> size (640x480). There are lots of problems with that photo beyond
> being limited to that small size!

Oh yeah. But without a cell phone, how would I get treasured concert pix
like this? http://photos1.blogger.com/blogger/1037/516/0/Image025-...

I think the problem was that I couldn't find a 3mm diameter UV filter.
Related resources
Can't find your answer ? Ask !
Anonymous
May 23, 2005 8:58:02 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Alan Browne wrote:
> http://www.canada.com/national/nationalpost/news/story....

"Galstian said the lens would work in cellphone cameras that take
notoriously poor quality images."

Well after that bit of wisdom, I ignored the rest of the story. The
best lens in the business is not going to help the pixel poor cell phone
image.

--
Joseph Meehan

Dia duit
Anonymous
May 23, 2005 9:08:04 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Joseph Meehan wrote:
> Alan Browne wrote:
>
>>http://www.canada.com/national/nationalpost/news/story....
>
>
> "Galstian said the lens would work in cellphone cameras that take
> notoriously poor quality images."
>
> Well after that bit of wisdom, I ignored the rest of the story. The
> best lens in the business is not going to help the pixel poor cell phone
> image.

Then you missed the rest that discsussed the potential for other camera
applications.

Cheers,
Alan



--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.
Anonymous
May 23, 2005 9:58:26 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
> On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
> <alan.browne@FreeLunchVideotron.ca> wrote:
>
>>
>>http://www.canada.com/national/nationalpost/news/story....
>
> That sounds a bit like the way our eyeballs focus. (Without the
> zooming capability of course).
>
> ..science mimicks nature...
>
> --
> Owamanga!
> http://www.pbase.com/owamanga

I saw a link last year like this. I think it used water and an electric
current.

The eye focuses with a jelly lens. the muscles surrounding it pull it
taught for distance focus and for close focusing relax. Once relaxed the
lens forms a more spherical shape which of course increases its refraction.
I'm not sure how this lens works exactly. I suppose electricity might cause
an expansion or contraction but i'm not sure how a laser would do it.
Perhaps it is heated, no that would normally make a sustance expand so that
would reduce the density. I'm not sure how a material would respond by
contracting. All in all it sounds expensive. Besides you nead a set of
lenses before you can zoom.
Anonymous
May 24, 2005 12:57:23 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Cynicor <j..tru.p.i.n...@speakeasy.net> writes:

> David Dyer-Bennet wrote:
>> My cell phone takes images which are *far* poorer than the pixel
>> limitations alone can excuse. Compare the first and second photos at
>> <http://www.dd-b.net/dd-b/SnapshotAlbum/data/2005/05310-...;;
>> the first one was taken with a Fuji S2, and resized to 700xwhatever.
>> The second was taken with my Nokia phone, and is the full original
>> size (640x480). There are lots of problems with that photo beyond
>> being limited to that small size!
>
> Oh yeah. But without a cell phone, how would I get treasured concert
> pix like this?
> http://photos1.blogger.com/blogger/1037/516/0/Image025-...

Boy, that *would* be hard to live without. I see your point.

> I think the problem was that I couldn't find a 3mm diameter UV filter.

Tape a bigger one on, covering the lens.
--
David Dyer-Bennet, <mailto:D d-b@dd-b.net>, <http://www.dd-b.net/dd-b/&gt;
RKBA: <http://noguns-nomoney.com/&gt; <http://www.dd-b.net/carry/&gt;
Pics: <http://dd-b.lighthunters.net/&gt; <http://www.dd-b.net/dd-b/SnapshotAlbum/&gt;
Dragaera/Steven Brust: <http://dragaera.info/&gt;
Anonymous
May 24, 2005 2:35:39 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian
lincoln <jessops@sux.com> writes
>
>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>> On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>> <alan.browne@FreeLunchVideotron.ca> wrote:
>>
>>>
>>>http://www.canada.com/national/nationalpost/news/story....
>>>8-d91e-4fb5-9856-68b72c5717e5
>>
>> That sounds a bit like the way our eyeballs focus. (Without the
>> zooming capability of course).
>>
>> ..science mimicks nature...
>>
>> --
>> Owamanga!
>> http://www.pbase.com/owamanga
>
>I saw a link last year like this. I think it used water and an electric
>current.
>
>The eye focuses with a jelly lens. the muscles surrounding it pull it
>taught for distance focus and for close focusing relax. Once relaxed the
>lens forms a more spherical shape which of course increases its refraction.
>I'm not sure how this lens works exactly. I suppose electricity might cause
>an expansion or contraction but i'm not sure how a laser would do it.
>Perhaps it is heated, no that would normally make a sustance expand so that
>would reduce the density. I'm not sure how a material would respond by
>contracting. All in all it sounds expensive. Besides you nead a set of
>lenses before you can zoom.
>
>
Actually, when you think about it, the human eye must be a zoom lens.
The effect of changing the curvature of the lens is to change its focal
length. Since the image distance is fixed, this also changes the
distance at which objects are in focus. So, what you need is not a set
of lenses, but an extendible eyeball!

David
--
David Littlewood
Anonymous
May 24, 2005 2:35:40 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"David Littlewood" <david@nospam.demon.co.uk> wrote in message
news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
> In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian lincoln
> <jessops@sux.com> writes
>>
>>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>>> On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>>> <alan.browne@FreeLunchVideotron.ca> wrote:
>>>
>>>>
>>>>http://www.canada.com/national/nationalpost/news/story....
>>>>8-d91e-4fb5-9856-68b72c5717e5
>>>
>>> That sounds a bit like the way our eyeballs focus. (Without the
>>> zooming capability of course).
>>>
>>> ..science mimicks nature...
>>>
>>> --
>>> Owamanga!
>>> http://www.pbase.com/owamanga
>>
>>I saw a link last year like this. I think it used water and an electric
>>current.
>>
>>The eye focuses with a jelly lens. the muscles surrounding it pull it
>>taught for distance focus and for close focusing relax. Once relaxed the
>>lens forms a more spherical shape which of course increases its
>>refraction.
>>I'm not sure how this lens works exactly. I suppose electricity might
>>cause
>>an expansion or contraction but i'm not sure how a laser would do it.
>>Perhaps it is heated, no that would normally make a sustance expand so
>>that
>>would reduce the density. I'm not sure how a material would respond by
>>contracting. All in all it sounds expensive. Besides you nead a set of
>>lenses before you can zoom.
>>
>>
> Actually, when you think about it, the human eye must be a zoom lens. The
> effect of changing the curvature of the lens is to change its focal
> length. Since the image distance is fixed, this also changes the distance
> at which objects are in focus. So, what you need is not a set of lenses,
> but an extendible eyeball!

Not really....It's field of view and magnification are fixed. It's auto
focus though. It would be interesting if there was an animal with a "zoom
eye". But I think it would have to have a multi-element lens, and I know of
no animal that has this......Perhaps in another few million years of
evolution.
Anonymous
May 24, 2005 4:31:49 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Cynicor wrote:
> David Dyer-Bennet wrote:
>
>> My cell phone takes images which are *far* poorer than the pixel
>> limitations alone can excuse. Compare the first and second photos at
>> <http://www.dd-b.net/dd-b/SnapshotAlbum/data/2005/05310-...;;
>> the first one was taken with a Fuji S2, and resized to 700xwhatever.
>> The second was taken with my Nokia phone, and is the full original
>> size (640x480). There are lots of problems with that photo beyond
>> being limited to that small size!
>
>
> Oh yeah. But without a cell phone, how would I get treasured concert pix
> like this?
> http://photos1.blogger.com/blogger/1037/516/0/Image025-...
>
> I think the problem was that I couldn't find a 3mm diameter UV filter.

I hear ya. Think that's bad? Try finding a 2-stop grad ND filter for
that puppy.

--
It Came From C. L. Smith's Unclaimed Mysteries.
http://www.unclaimedmysteries.net
Anonymous
May 24, 2005 4:50:52 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

William Graham wrote:
> "David Littlewood" <david@nospam.demon.co.uk> wrote in message
> news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>
>>In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian lincoln
>><jessops@sux.com> writes
>>
>>>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>>>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>>>
>>>>On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>>>><alan.browne@FreeLunchVideotron.ca> wrote:
>>>>
>>>>
>>>>>http://www.canada.com/national/nationalpost/news/story....
>>>>>8-d91e-4fb5-9856-68b72c5717e5
>>>>
>>>>That sounds a bit like the way our eyeballs focus. (Without the
>>>>zooming capability of course).
>>>>
>>>>..science mimicks nature...
>>>>
>>>>--
>>>>Owamanga!
>>>>http://www.pbase.com/owamanga
>>>
>>>I saw a link last year like this. I think it used water and an electric
>>>current.
>>>
>>>The eye focuses with a jelly lens. the muscles surrounding it pull it
>>>taught for distance focus and for close focusing relax. Once relaxed the
>>>lens forms a more spherical shape which of course increases its
>>>refraction.
>>>I'm not sure how this lens works exactly. I suppose electricity might
>>>cause
>>>an expansion or contraction but i'm not sure how a laser would do it.
>>>Perhaps it is heated, no that would normally make a sustance expand so
>>>that
>>>would reduce the density. I'm not sure how a material would respond by
>>>contracting. All in all it sounds expensive. Besides you nead a set of
>>>lenses before you can zoom.
>>>
>>>
>>
>>Actually, when you think about it, the human eye must be a zoom lens. The
>>effect of changing the curvature of the lens is to change its focal
>>length. Since the image distance is fixed, this also changes the distance
>>at which objects are in focus. So, what you need is not a set of lenses,
>>but an extendible eyeball!
>
>
> Not really....It's field of view and magnification are fixed. It's auto
> focus though. It would be interesting if there was an animal with a "zoom
> eye". But I think it would have to have a multi-element lens, and I know of
> no animal that has this......Perhaps in another few million years of
> evolution.
>
>
No? What about Eagles and other birds of prey? Their vision manages to
get that effect, somehow.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 4:50:53 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"Ron Hunter" <rphunter@charter.net> wrote in message
news:1hzke.13746$bD5.5412@fe07.lga...
> William Graham wrote:
>> "David Littlewood" <david@nospam.demon.co.uk> wrote in message
>> news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>>
>>>In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian
>>>lincoln <jessops@sux.com> writes
>>>
>>>>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>>>>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>>>>
>>>>>On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>>>>><alan.browne@FreeLunchVideotron.ca> wrote:
>>>>>
>>>>>
>>>>>>http://www.canada.com/national/nationalpost/news/story....
>>>>>>8-d91e-4fb5-9856-68b72c5717e5
>>>>>
>>>>>That sounds a bit like the way our eyeballs focus. (Without the
>>>>>zooming capability of course).
>>>>>
>>>>>..science mimicks nature...
>>>>>
>>>>>--
>>>>>Owamanga!
>>>>>http://www.pbase.com/owamanga
>>>>
>>>>I saw a link last year like this. I think it used water and an electric
>>>>current.
>>>>
>>>>The eye focuses with a jelly lens. the muscles surrounding it pull it
>>>>taught for distance focus and for close focusing relax. Once relaxed
>>>>the
>>>>lens forms a more spherical shape which of course increases its
>>>>refraction.
>>>>I'm not sure how this lens works exactly. I suppose electricity might
>>>>cause
>>>>an expansion or contraction but i'm not sure how a laser would do it.
>>>>Perhaps it is heated, no that would normally make a sustance expand so
>>>>that
>>>>would reduce the density. I'm not sure how a material would respond by
>>>>contracting. All in all it sounds expensive. Besides you nead a set of
>>>>lenses before you can zoom.
>>>>
>>>>
>>>
>>>Actually, when you think about it, the human eye must be a zoom lens. The
>>>effect of changing the curvature of the lens is to change its focal
>>>length. Since the image distance is fixed, this also changes the distance
>>>at which objects are in focus. So, what you need is not a set of lenses,
>>>but an extendible eyeball!
>>
>>
>> Not really....It's field of view and magnification are fixed. It's auto
>> focus though. It would be interesting if there was an animal with a "zoom
>> eye". But I think it would have to have a multi-element lens, and I know
>> of no animal that has this......Perhaps in another few million years of
>> evolution.
> No? What about Eagles and other birds of prey? Their vision manages to
> get that effect, somehow.
>
Eagles and hawks get their superb vision from an inordinately large number
of very sensitive rods and cones in their retinas. Otherwise, their eyes
work exactly as do ours......
Anonymous
May 24, 2005 6:43:55 AM

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

On Tue, 24 May 2005 00:50:52 -0500, Ron Hunter wrote:

>> It would be interesting if there was an animal with a "zoom eye".
>> But I think it would have to have a multi-element lens, and I know
>> of no animal that has this......Perhaps in another few million years of
>> evolution.
>
> No? What about Eagles and other birds of prey? Their vision
> manages to get that effect, somehow.

But having a "zoom eye" would be tantamount to cheating. Who'd
have thought eagles and falcons would stoop so low?

(!)
Anonymous
May 24, 2005 1:22:42 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

In article <syMhCZJrykkCFwUJ@dlittlewood.co.uk>, david@nospam.demon.co.uk
says...
> Actually, when you think about it, the human eye must be a zoom lens.
> The effect of changing the curvature of the lens is to change its focal
> length. Since the image distance is fixed, this also changes the
> distance at which objects are in focus. So, what you need is not a set
> of lenses, but an extendible eyeball!
>
I had one of those when I was young and a pretty girl walked by.
Anonymous
May 24, 2005 1:40:57 PM

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

ASAAR wrote:
> On Tue, 24 May 2005 00:50:52 -0500, Ron Hunter wrote:
>
>
>>>It would be interesting if there was an animal with a "zoom eye".
>>>But I think it would have to have a multi-element lens, and I know
>>>of no animal that has this......Perhaps in another few million years of
>>>evolution.
>>
>>No? What about Eagles and other birds of prey? Their vision
>>manages to get that effect, somehow.
>
>
> But having a "zoom eye" would be tantamount to cheating. Who'd
> have thought eagles and falcons would stoop so low?
>
> (!)
>
They aren't concerned about cheating, they are concerned about EATING.
Grin.
Natural selection at work.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 1:41:32 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Stacey wrote:
> Alan Browne wrote:
>
>
>>
> http://www.canada.com/national/nationalpost/news/story....
>
>>
>
>
> There can't be any optical improvements possible over what you're using
> now Alan...
Of course not, everyone knows nothing has been invented since 1920... Grin.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 1:42:26 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

William Graham wrote:
> "Ron Hunter" <rphunter@charter.net> wrote in message
> news:1hzke.13746$bD5.5412@fe07.lga...
>
>>William Graham wrote:
>>
>>>"David Littlewood" <david@nospam.demon.co.uk> wrote in message
>>>news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>>>
>>>
>>>>In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian
>>>>lincoln <jessops@sux.com> writes
>>>>
>>>>
>>>>>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>>>>>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>>>>>
>>>>>
>>>>>>On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>>>>>><alan.browne@FreeLunchVideotron.ca> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>>http://www.canada.com/national/nationalpost/news/story....
>>>>>>>8-d91e-4fb5-9856-68b72c5717e5
>>>>>>
>>>>>>That sounds a bit like the way our eyeballs focus. (Without the
>>>>>>zooming capability of course).
>>>>>>
>>>>>>..science mimicks nature...
>>>>>>
>>>>>>--
>>>>>>Owamanga!
>>>>>>http://www.pbase.com/owamanga
>>>>>
>>>>>I saw a link last year like this. I think it used water and an electric
>>>>>current.
>>>>>
>>>>>The eye focuses with a jelly lens. the muscles surrounding it pull it
>>>>>taught for distance focus and for close focusing relax. Once relaxed
>>>>>the
>>>>>lens forms a more spherical shape which of course increases its
>>>>>refraction.
>>>>>I'm not sure how this lens works exactly. I suppose electricity might
>>>>>cause
>>>>>an expansion or contraction but i'm not sure how a laser would do it.
>>>>>Perhaps it is heated, no that would normally make a sustance expand so
>>>>>that
>>>>>would reduce the density. I'm not sure how a material would respond by
>>>>>contracting. All in all it sounds expensive. Besides you nead a set of
>>>>>lenses before you can zoom.
>>>>>
>>>>>
>>>>
>>>>Actually, when you think about it, the human eye must be a zoom lens. The
>>>>effect of changing the curvature of the lens is to change its focal
>>>>length. Since the image distance is fixed, this also changes the distance
>>>>at which objects are in focus. So, what you need is not a set of lenses,
>>>>but an extendible eyeball!
>>>
>>>
>>>Not really....It's field of view and magnification are fixed. It's auto
>>>focus though. It would be interesting if there was an animal with a "zoom
>>>eye". But I think it would have to have a multi-element lens, and I know
>>>of no animal that has this......Perhaps in another few million years of
>>>evolution.
>>
>>No? What about Eagles and other birds of prey? Their vision manages to
>>get that effect, somehow.
>>
>
> Eagles and hawks get their superb vision from an inordinately large number
> of very sensitive rods and cones in their retinas. Otherwise, their eyes
> work exactly as do ours......
>
>
I suspect you will find their lens will also have a great deal of extra
shape changing ability.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 2:44:45 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Alan Browne wrote:
>
> http://www.canada.com/national/nationalpost/news/story....
>
> --
> -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
> -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
> -- [SI] gallery & rulz: http://www.pbase.com/shootin
> -- e-meil: Remove FreeLunch.

Clearly the paper's date was wrong. It should have been 1st April, not
22nd May.

Colin
Anonymous
May 24, 2005 3:25:01 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

David Dyer-Bennet wrote:
> Cynicor <j..tru.p.i.n...@speakeasy.net> writes:
>
>> David Dyer-Bennet wrote:
>>> My cell phone takes images which are *far* poorer than the pixel
>>> limitations alone can excuse. Compare the first and second photos
>>> at
>>> <http://www.dd-b.net/dd-b/SnapshotAlbum/data/2005/05310-...;;
>>> the first one was taken with a Fuji S2, and resized to
>>> 700xwhatever. The second was taken with my Nokia phone, and is the
>>> full original size (640x480). There are lots of problems with that
>>> photo beyond being limited to that small size!
>>
>> Oh yeah. But without a cell phone, how would I get treasured concert
>> pix like this?
>> http://photos1.blogger.com/blogger/1037/516/0/Image025-...
>
> Boy, that *would* be hard to live without. I see your point.
>
>> I think the problem was that I couldn't find a 3mm diameter UV
>> filter.
>
> Tape a bigger one on, covering the lens.

Be sure to use clear tape.

--
Joseph Meehan

Dia duit
Anonymous
May 24, 2005 4:04:08 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Joseph Meehan wrote:
> Alan Browne wrote:
> >
http://www.canada.com/national/nationalpost/news/story....
>
> "Galstian said the lens would work in cellphone cameras that take
> notoriously poor quality images."
>
> Well after that bit of wisdom, I ignored the rest of the story.
The
> best lens in the business is not going to help the pixel poor cell
phone
> image.

Would you call 5MP cellphone camera pixel poor? Ok, the pixel quality
won't match the pixel quality of a good P&S or a dSLR sensor but I am
sure the electronics of the cellphone cameras will soon catchup with
P&S sensors atleast. Optics is another matter.

http://www.pcworld.com/news/article/0,aid,118260,00.asp

- Siddhartha
Anonymous
May 24, 2005 4:28:32 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"David Littlewood" <david@nospam.demon.co.uk> wrote in message
news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
> Actually, when you think about it, the human eye must be a zoom lens. The
> effect of changing the curvature of the lens is to change its focal
> length. Since the image distance is fixed, this also changes the distance
> at which objects are in focus. So, what you need is not a set of lenses,
> but an extendible eyeball!
>
> David
> --
> David Littlewood

Nope. Rather than move forward and backward the eye lens changes shape and
hence its refractive properties. You would need a moving second lens in
order to become a zoom.

Cheaper lenses focus by moving the front element. Internal focusing ones
still move a lens in and out but the outer most element doesn't budge. To
qualify as a zoom or vari focal length requires more.
Anonymous
May 24, 2005 4:30:37 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"William Graham" <weg9@comcast.net> wrote in message
news:o s-dnWdCV6NyBQ_fRVn-3w@comcast.com...
>
> "David Littlewood" <david@nospam.demon.co.uk> wrote in message
> news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>> In article <6Roke.115026$Cq2.43776@fe2.news.blueyonder.co.uk>, ian
>> lincoln <jessops@sux.com> writes
>>>
>>>"Owamanga" <owamanga(not-this-bit)@hotmail.com> wrote in message
>>>news:ri3491p7dp4q2rvp5hieb1en5o9rhco8pn@4ax.com...
>>>> On Mon, 23 May 2005 12:36:26 -0400, Alan Browne
>>>> <alan.browne@FreeLunchVideotron.ca> wrote:
>>>>
>>>>>
>>>>>http://www.canada.com/national/nationalpost/news/story....
>>>>>8-d91e-4fb5-9856-68b72c5717e5
>>>>
>>>> That sounds a bit like the way our eyeballs focus. (Without the
>>>> zooming capability of course).
>>>>
>>>> ..science mimicks nature...
>>>>
>>>> --
>>>> Owamanga!
>>>> http://www.pbase.com/owamanga
>>>
>>>I saw a link last year like this. I think it used water and an electric
>>>current.
>>>
>>>The eye focuses with a jelly lens. the muscles surrounding it pull it
>>>taught for distance focus and for close focusing relax. Once relaxed the
>>>lens forms a more spherical shape which of course increases its
>>>refraction.
>>>I'm not sure how this lens works exactly. I suppose electricity might
>>>cause
>>>an expansion or contraction but i'm not sure how a laser would do it.
>>>Perhaps it is heated, no that would normally make a sustance expand so
>>>that
>>>would reduce the density. I'm not sure how a material would respond by
>>>contracting. All in all it sounds expensive. Besides you nead a set of
>>>lenses before you can zoom.
>>>
>>>
>> Actually, when you think about it, the human eye must be a zoom lens. The
>> effect of changing the curvature of the lens is to change its focal
>> length. Since the image distance is fixed, this also changes the distance
>> at which objects are in focus. So, what you need is not a set of lenses,
>> but an extendible eyeball!
>
> Not really....It's field of view and magnification are fixed. It's auto
> focus though. It would be interesting if there was an animal with a "zoom
> eye". But I think it would have to have a multi-element lens, and I know
> of no animal that has this......Perhaps in another few million years of
> evolution.

The closest are birds of prey. I think the centre section of the high has
amazing resolution and the periphery is normal. So not only a more
sophisticated retina but a highly refractive cornea. Thats how they can
hover several hundred feet and then dive bomb.
Anonymous
May 24, 2005 4:34:59 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

On Tue, 24 May 2005 00:45:30 -0700, "William Graham"
<weg9@comcast.net> wrote:

>
>"Ron Hunter" <rphunter@charter.net> wrote in message
>news:1hzke.13746$bD5.5412@fe07.lga...
>
>> No? What about Eagles and other birds of prey? Their vision manages to
>> get that effect, somehow.
>>
>Eagles and hawks get their superb vision from an inordinately large number
>of very sensitive rods and cones in their retinas. Otherwise, their eyes
>work exactly as do ours......

I'm no expert, but the few nature programs I've watched about these
seemed to suggest they have high sensitivity in a particular area only
- the rest of their eye is wide-angle motion sensitive. You could
argue a human eye is somewhat similar, but I think the difference
between the sensitive area and motion-sensitive areas in a bird of
prey is much more significant than on a predatory mammal such as us.

--
Owamanga!
http://www.pbase.com/owamanga
Anonymous
May 24, 2005 4:35:00 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Owamanga wrote:
> On Tue, 24 May 2005 00:45:30 -0700, "William Graham"
> <weg9@comcast.net> wrote:
>
>
>>"Ron Hunter" <rphunter@charter.net> wrote in message
>>news:1hzke.13746$bD5.5412@fe07.lga...
>>
>>
>>>No? What about Eagles and other birds of prey? Their vision manages to
>>>get that effect, somehow.
>>>
>>
>>Eagles and hawks get their superb vision from an inordinately large number
>>of very sensitive rods and cones in their retinas. Otherwise, their eyes
>>work exactly as do ours......
>
>
> I'm no expert, but the few nature programs I've watched about these
> seemed to suggest they have high sensitivity in a particular area only
> - the rest of their eye is wide-angle motion sensitive. You could
> argue a human eye is somewhat similar, but I think the difference
> between the sensitive area and motion-sensitive areas in a bird of
> prey is much more significant than on a predatory mammal such as us.
>
> --
> Owamanga!
> http://www.pbase.com/owamanga
In order to fly safely, and avoid predators themselves, they require a
good motion sensitivity. In order to find prey, they also have great
acuity. However, their eyes are adapted to longer range vision than ours.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 4:35:01 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

In article <b5Hke.14436$bD5.8286@fe07.lga>,
Ron Hunter <rphunter@charter.net> wrote:
>Owamanga wrote:
>> On Tue, 24 May 2005 00:45:30 -0700, "William Graham"
>> <weg9@comcast.net> wrote:
>>
>>
>>>"Ron Hunter" <rphunter@charter.net> wrote in message
>>>news:1hzke.13746$bD5.5412@fe07.lga...
>>>
>>>
>>>>No? What about Eagles and other birds of prey? Their vision manages to
>>>>get that effect, somehow.
>>>>
>>>
>>>Eagles and hawks get their superb vision from an inordinately large number
>>>of very sensitive rods and cones in their retinas. Otherwise, their eyes
>>>work exactly as do ours......

So, digital zoom.


>> I'm no expert, but the few nature programs I've watched about these
>> seemed to suggest they have high sensitivity in a particular area only
>> - the rest of their eye is wide-angle motion sensitive. You could
>> argue a human eye is somewhat similar, but I think the difference
>> between the sensitive area and motion-sensitive areas in a bird of
>> prey is much more significant than on a predatory mammal such as us.
>>
>> --
>> Owamanga!
>> http://www.pbase.com/owamanga
>In order to fly safely, and avoid predators themselves, they require a
>good motion sensitivity. In order to find prey, they also have great
>acuity. However, their eyes are adapted to longer range vision than ours.
>
>
>--
>Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 4:53:37 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Stacey wrote:
> There can't be any optical improvements possible over what you're using
> now Alan...
> --

Are you absolutely sure?

http://www.dtic.mil/matris/sbir/sbir043/sbir446.html
Image Intensified Lightweight Lens Development

http://optics.nasa.gov/current.html
Adjustable Focus Optical Correction Lens

http://www.physorg.com/news612.html
Ceramic lens

http://www.physorg.com/news3829.html
Nano-sharp images

http://news.bbc.co.uk/2/hi/technology/3643964.stm

http://uanews.org/cgi-bin/WebObjects/UANews.woa/2/wa/En...
Anonymous
May 24, 2005 6:11:55 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

In article <Q5Fke.90377$a9.18724@fe3.news.blueyonder.co.uk>, ian lincoln
<jessops@sux.com> writes
>
>"David Littlewood" <david@nospam.demon.co.uk> wrote in message
>news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>> Actually, when you think about it, the human eye must be a zoom lens. The
>> effect of changing the curvature of the lens is to change its focal
>> length. Since the image distance is fixed, this also changes the distance
>> at which objects are in focus. So, what you need is not a set of lenses,
>> but an extendible eyeball!
>>
>> David
>> --
>> David Littlewood
>
>Nope. Rather than move forward and backward the eye lens changes shape and
>hence its refractive properties. You would need a moving second lens in
>order to become a zoom.

I think you are completely missing the point. If you change the
curvature of a lens, you change its focal length. This makes the eye a
zoom, or more accurately a vari-focal lens, albeit (as I said) one which
lacks the ability to vary the image distance.
>
>Cheaper lenses focus by moving the front element. Internal focusing ones
>still move a lens in and out but the outer most element doesn't budge. To
>qualify as a zoom or vari focal length requires more.
>
Simple (not necessarily cheap) lenses (whether zoom or fixed focal
length) focus by moving the whole lens in or out, not just the "front
element". However, this is not relevant to the point at issue.
--
David Littlewood
Anonymous
May 24, 2005 6:22:48 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

"tjab" <tjab@wam.umd.edu> wrote in message
news:D 6vhd3$f4t@rac3.wam.umd.edu...
> In article <b5Hke.14436$bD5.8286@fe07.lga>,
> Ron Hunter <rphunter@charter.net> wrote:
>>Owamanga wrote:
>>> On Tue, 24 May 2005 00:45:30 -0700, "William Graham"
>>> <weg9@comcast.net> wrote:
>>>
>>>
>>>>"Ron Hunter" <rphunter@charter.net> wrote in message
>>>>news:1hzke.13746$bD5.5412@fe07.lga...
>>>>
>>>>
>>>>>No? What about Eagles and other birds of prey? Their vision manages
>>>>>to
>>>>>get that effect, somehow.
>>>>>
>>>>
>>>>Eagles and hawks get their superb vision from an inordinately large
>>>>number
>>>>of very sensitive rods and cones in their retinas. Otherwise, their eyes
>>>>work exactly as do ours......
>
> So, digital zoom.

This could be....Perhaps not "digital" but the brain could well do a mental
zoom in its processing.....Unfortunately, this is hard to know with our
present technology.....
Anonymous
May 24, 2005 6:34:51 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Bruce Graham wrote:
>
> In article <syMhCZJrykkCFwUJ@dlittlewood.co.uk>, david@nospam.demon.co.uk
> says...
> > Actually, when you think about it, the human eye must be a zoom lens.
> > The effect of changing the curvature of the lens is to change its focal
> > length. Since the image distance is fixed, this also changes the
> > distance at which objects are in focus. So, what you need is not a set
> > of lenses, but an extendible eyeball!
> >
> I had one of those when I was young and a pretty girl walked by.

He said EYE-ball.

Colin
Anonymous
May 24, 2005 6:51:45 PM

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

On Tue, 24 May 2005 09:40:57 -0500, Ron Hunter wrote:

>> But having a "zoom eye" would be tantamount to cheating. Who'd
>> have thought eagles and falcons would stoop so low?
>>
>> (!)
>>
> They aren't concerned about cheating, they are concerned about EATING.
> Grin.
> Natural selection at work.

I only use "cheating" to set up the pun. Unless you noticed it,
look again. :) 
Anonymous
May 24, 2005 7:02:21 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Marvin wrote:
> Alan Browne wrote:
>
>>
>> http://www.canada.com/national/nationalpost/news/story....
>>
>
>
> Perhaps. Not everything that is patented turns out to be as good as the
> inventor thinks. Wait and see.
Also, the alternative liquid lens looks like a good possibility. But
there is more than a lens to deal with. The sensor, and support
processing hardware needs to be improved, and phones need more ram.
Sure, the day will come when you see a 10X zoom and 5mp in a phone, but
give it about 5 years.


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 7:04:44 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Siddhartha Jain wrote:
> Joseph Meehan wrote:
>
>>Alan Browne wrote:
>>
> http://www.canada.com/national/nationalpost/news/story....
>
>>"Galstian said the lens would work in cellphone cameras that take
>>notoriously poor quality images."
>>
>> Well after that bit of wisdom, I ignored the rest of the story.
>
> The
>
>>best lens in the business is not going to help the pixel poor cell
>
> phone
>
>>image.
>
>
> Would you call 5MP cellphone camera pixel poor? Ok, the pixel quality
> won't match the pixel quality of a good P&S or a dSLR sensor but I am
> sure the electronics of the cellphone cameras will soon catchup with
> P&S sensors atleast. Optics is another matter.
>
> http://www.pcworld.com/news/article/0,aid,118260,00.asp
>
> - Siddhartha
>
Well, if the cell phone companies would be less concerned with trying to
make the phones too small for human hands, there wouldn't be quite so
much of a problem...


--
Ron Hunter rphunter@charter.net
Anonymous
May 24, 2005 7:16:01 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Colin D wrote:
>
> Bruce Graham wrote:
> >
> > In article <syMhCZJrykkCFwUJ@dlittlewood.co.uk>, david@nospam.demon.co.uk
> > says...
> > > Actually, when you think about it, the human eye must be a zoom lens.
> > > The effect of changing the curvature of the lens is to change its focal
> > > length. Since the image distance is fixed, this also changes the
> > > distance at which objects are in focus. So, what you need is not a set
> > > of lenses, but an extendible eyeball!
> > >
> > I had one of those when I was young and a pretty girl walked by.
>
> He said EYE-ball.
>
> Colin

Oops - forgot the smiley {:-)

Colin
May 24, 2005 10:19:03 PM

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

On Tue, 24 May 2005 09:40:57 -0500
In message <_1Hke.14433$bD5.10181@fe07.lga>
Ron Hunter <rphunter@charter.net> wrote:

> > > What about Eagles and other birds of prey?
> >
> > But having a "zoom eye" would be tantamount to cheating.
>
> They aren't concerned about cheating, they are concerned about EATING.

LOL...

Jeff (I just wanted to remember this exchange ;-)
Anonymous
May 24, 2005 11:42:02 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Ron Hunter <rphunter@charter.net> writes:

>No? What about Eagles and other birds of prey? Their vision manages to
>get that effect, somehow.

They have a relatively large eyeball, and thus a long focal length lens
(compared to most animals). And they must have a high cone density in
the fovea of the eye, to increase resolution.

Dave
Anonymous
May 24, 2005 11:42:03 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Dave Martindale wrote:
> Ron Hunter <rphunter@charter.net> writes:
>
>
>>No? What about Eagles and other birds of prey? Their vision manages to
>>get that effect, somehow.
>
>
> They have a relatively large eyeball, and thus a long focal length lens
> (compared to most animals). And they must have a high cone density in
> the fovea of the eye, to increase resolution.
>
> Dave
>
Birds of prey also have what could be called telscopic vision. A
falcon can see a small rodent from 3 kilometers, two miles, away. That
is about the the same as if a person could read a newspaper about 25
meters, nearly 30 yards.

adding some more details to the clear answer earlier. Some birds of pray
have eyes with two focal points (the area of what we see clearly and
focus on). For focusing on near and far at the same time.

The above from www.answerbag.com


--
Ron Hunter rphunter@charter.net
Anonymous
May 25, 2005 1:16:35 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

David Littlewood wrote:
> In article <Q5Fke.90377$a9.18724@fe3.news.blueyonder.co.uk>, ian lincoln
> <jessops@sux.com> writes
>
>>
>> "David Littlewood" <david@nospam.demon.co.uk> wrote in message
>> news:syMhCZJrykkCFwUJ@dlittlewood.co.uk...
>>
>>> Actually, when you think about it, the human eye must be a zoom lens.
>>> The
>>> effect of changing the curvature of the lens is to change its focal
>>> length. Since the image distance is fixed, this also changes the
>>> distance
>>> at which objects are in focus. So, what you need is not a set of lenses,
>>> but an extendible eyeball!
>>>
>>> David
>>> --
>>> David Littlewood
>>
>>
>> Nope. Rather than move forward and backward the eye lens changes
>> shape and
>> hence its refractive properties. You would need a moving second lens in
>> order to become a zoom.
>
>
> I think you are completely missing the point. If you change the
> curvature of a lens, you change its focal length. This makes the eye a
> zoom, or more accurately a vari-focal lens, albeit (as I said) one which
> lacks the ability to vary the image distance.
>
>>
>> Cheaper lenses focus by moving the front element. Internal focusing ones
>> still move a lens in and out but the outer most element doesn't
>> budge. To
>> qualify as a zoom or vari focal length requires more.
>>
> Simple (not necessarily cheap) lenses (whether zoom or fixed focal
> length) focus by moving the whole lens in or out, not just the "front
> element". However, this is not relevant to the point at issue.
The human eye has two ways to affect 'zoom'. First, it can vary the
shape of the lens, and second it can vary the aperture. The combination
of those can render something almost like a zoom by changing the focal
length of the lens, then narrowing the aperture to extend the sharpness
distance so that a good image still falls on the fovea. The massively
parallel processing in the brain can clean up the noise, and compensate
to some degree for focus. Birds of prey seem able to even change the
shape of the eyeball, and to 'boost' the output of the rods for night
vision. Of course, those birds have a lot greater percentage of their
brain devoted to vision than we do.


--
Ron Hunter rphunter@charter.net
May 25, 2005 3:07:44 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Siddhartha Jain wrote:

> Stacey wrote:
>> There can't be any optical improvements possible over what you're using
>> now Alan...
>> --
>
> Are you absolutely sure?
>

Yes because Alan told me so! :-)
--

Stacey
Anonymous
May 25, 2005 3:15:03 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

losttoy@gmail.com (Siddhartha Jain) wrote in
<1116961448.813047.205070@o13g2000cwo.googlegroups.com>:

>
>Would you call 5MP cellphone camera pixel poor? Ok, the pixel
>quality won't match the pixel quality of a good P&S or a dSLR sensor
>but I am sure the electronics of the cellphone cameras will soon
>catchup with P&S sensors atleast. Optics is another matter.

Size matters and that's the trouble. Look at the P&S now a days. The
Ixus 430 is ok with ISO 50, but already with ISO 100 the noise is
visible. Of course, you can try to elimenate the noise, somehow... but
then, what is noise, and what is part of the picture?
And it's hard to bend physics. Either that or the industrie is lowering
our standards.

-Leonhard
Anonymous
May 25, 2005 3:38:37 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Stacey wrote:
> Siddhartha Jain wrote:
>
> > Stacey wrote:
> >> There can't be any optical improvements possible over what you're using
> >> now Alan...
> >> --
> >
> > Are you absolutely sure?
> >
>
> Yes because Alan told me so! :-)

LOL :) )
Anonymous
May 25, 2005 3:42:43 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Ron Hunter wrote:
> Well, if the cell phone companies would be less concerned with trying to
> make the phones too small for human hands, there wouldn't be quite so
> much of a problem...
>

Then probably what you need is the Samsung SCH-V770. 7MP camera phone
with 3x optical zoom.
http://cellphones.engadget.com/entry/1234000847036344/

If you can't fit a decent camera in a phone then retrofit a phone in a
P&S camera ;) 

- Siddhartha
Anonymous
May 25, 2005 3:46:05 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Ron Hunter wrote:
> > Perhaps. Not everything that is patented turns out to be as good as the
> > inventor thinks. Wait and see.
> Also, the alternative liquid lens looks like a good possibility. But
> there is more than a lens to deal with. The sensor, and support
> processing hardware needs to be improved, and phones need more ram.
> Sure, the day will come when you see a 10X zoom and 5mp in a phone, but
> give it about 5 years.

Again, not 10x yet but 7MP and 3x optical zoom with a 1/8" CCD is what
you can get in a cellphone.
http://cellphones.engadget.com/entry/1234000847036344/

I think you will want to revise that five year limit :-)

- Siddhartha
Anonymous
May 25, 2005 4:08:48 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Ron Hunter wrote:
> Which way? I am always amazed at how fast things can change in such a
> volatile industry. Look at the state of the cell phone art 5 years ago.
>

As if a megapixel camera phone wasn't enough, Samsung went ahead and
put a satellite TV in a phone.
http://www.engadget.com/entry/1234000763026569/

Apparently, its already on sale in S.Korea!!

I think the whole thing is driven by cellphone technology - GSM vs CDMA
and the role of regulators. Korea and Japan have taken the lead and
gone ahead with CDMA EV-DO technology that allows 2Mpbs transfer rates
for each phone!! That means you can transfer all those 7MP files to
your friends and watch streaming video. This is in sharp contrast to
countries like US which have big parts of their telecom networks still
running on legacy technology and various telcos lobbying with the FCC
for skewed technology standards.

- Siddhartha
Anonymous
May 25, 2005 5:56:29 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Siddhartha Jain wrote:
> Ron Hunter wrote:
>
>>>Perhaps. Not everything that is patented turns out to be as good as the
>>>inventor thinks. Wait and see.
>>
>>Also, the alternative liquid lens looks like a good possibility. But
>>there is more than a lens to deal with. The sensor, and support
>>processing hardware needs to be improved, and phones need more ram.
>>Sure, the day will come when you see a 10X zoom and 5mp in a phone, but
>>give it about 5 years.
>
>
> Again, not 10x yet but 7MP and 3x optical zoom with a 1/8" CCD is what
> you can get in a cellphone.
> http://cellphones.engadget.com/entry/1234000847036344/
>
> I think you will want to revise that five year limit :-)
>
> - Siddhartha
>
Which way? I am always amazed at how fast things can change in such a
volatile industry. Look at the state of the cell phone art 5 years ago.


--
Ron Hunter rphunter@charter.net
Anonymous
May 25, 2005 8:04:46 AM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

David Littlewood <david@nospam.demon.co.uk> writes:

>I think you are completely missing the point. If you change the
>curvature of a lens, you change its focal length. This makes the eye a
>zoom, or more accurately a vari-focal lens, albeit (as I said) one which
>lacks the ability to vary the image distance.

I don't think you can call a lens a zoom unless it can change
magnification without losing focus, and without moving the subject.
The focal length changes and so magnification changes, but the focal
plane remains in the same spot.

A lens that changes the focal length, like the eye, is just providing a
different way of achieving focus. For a given subject position, there
is (at most) one focal length setting that gives an in-focus image.

Dave
Anonymous
May 25, 2005 1:45:22 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

I see a gradual change in language occurring. This is similar to what
happened to the term "telephoto". Originally the term referred to a
lens whose apparent focal length was greater than the distance from the
center of lens to focal plane. Gradually the term has come to mean ANY
long focal length lens (efl greater than diagonal of format).

Now, the term "zoom", which originally meant a lens whose efl could be
changed, is now coming to mean the same as telephoto. Look at the
number of people who ask, if I buy a lens with (whatever)X zoom, how big
will the picture look.

Personally, I don't like this change in meaning that is happening, but
just as Knute couldn't hold back the tide, I suspect there is nothing
any of us can do to impede changes in the English language.
Anonymous
May 25, 2005 1:49:56 PM

Archived from groups: rec.photo.equipment.35mm,rec.photo.digital (More info?)

Ron Hunter wrote:

> In order to fly safely, and avoid predators themselves, they require a
> good motion sensitivity. In order to find prey, they also have great
> acuity. However, their eyes are adapted to longer range vision than ours.
>
>
Eagles and birds of prey have an eye whose efl is much greater in
proportion to the size of the head than primates. It is not that much
different from human eye. From what I have read the photo recepter
density is somewhat greater than humans. However, the visual skills of
these birds is apparently, as Ron indicates, due to processing skills
more than optics.

The human vision system is marvelously flexible, and can do MANY tasks.
We give up some specialization, but many visual skills can be TAUGHT,
and with practice people with normal eyesight can do seemingly amazing
tricks.

One trick we still have is detecting very small MOTION in the visual
field. This is one of the tricks that birds of prey still use.
!