Optical illusion?

Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.
-Rich

Air is the difference. The light has to pass through more air, dust and particulates that
effect the resultant picture. There are other optical aberrations that come into effect on
long distance shots such as heat rising and temperature inversions.

--
Dave




"RichA" wrote in message news | Ever notice how a long distance shot doesn't
| ever look as sharp as a close-up shot?
| It's got to be some kind of optical illusion
| because lenses (I believe) are optimized for
| infinity imaging. But, case in point;
| When a friend was looking for a digital,
| I showed him two shots from mine, one a landscape,
| the other a macro. The landscape didn't impress
| him technically (sharpness, etc) but the macro convinced
| him to get the camera.
| -Rich

"RichA" wrote in message
news
Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.
-Rich

Interesting observation...
I just decided to play around with panorama stich on my 20D. I also took the
same shots with a GWS Fuji 120 roll film, pano camera. I don't think I'll be
converting from film to digital for Panos just yet! It seems taht the
further away you get, the less detail is recorded.

Doug

"RichA" wrote in message news
Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.

Besides the atmospheric obscurants inherent in any image taken over long distances the simple
fact remains that digital cameras still have a long way to go with regards to sensor and image
resolution. Objects that are small in an image are represented my just a few pixels and you
cannot get a lot of sharp detail when you have so few pixels to work with.

A fascinating project that is being worked on to produce Giga-Pixel images can be found at
the link below.

http://www.scienceblog.com/community/article4901.html

On Sat, 01 Jan 2005 04:18:15 GMT, "Ken" wrote:


"RichA" wrote in message news
Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.

Besides the atmospheric obscurants inherent in any image taken over long distances the simple
fact remains that digital cameras still have a long way to go with regards to sensor and image
resolution. Objects that are small in an image are represented my just a few pixels and you
cannot get a lot of sharp detail when you have so few pixels to work with.

A fascinating project that is being worked on to produce Giga-Pixel images can be found at
the link below.

http://www.scienceblog.com/community/article4901.html


But it's using a conventional film camera, big plates and it's
converted to digital via a scanner.
I thought it was something like this:

http://www.cfht.hawaii.edu/HawaiianStarlight/

A true, 338 megapixel camera set-up.


Taking advantage of the rapid evolution of optical electronic
detectors (CCDs) over the past two decades, CFHT is now able to cover
most of its useful field of view with a detector 40 times more
sensitive than the photographic plates! The MegaPrime imager which
includes the MegaCam camera, a mosaic of forty individual CCD
detectors, is the largest close-packed array in use in the world today
(~18,400 x 18,400 pixels).

On Sat, 01 Jan 2005 01:25:42 GMT, "David H. Lipman"
wrote:

Air is the difference. The light has to pass through more air, dust and particulates that
effect the resultant picture. There are other optical aberrations that come into effect on
long distance shots such as heat rising and temperature inversions.

I should have also said, objects no more than 30 feet away don't look
as good as close-up shots in terms of subjective sharpness either.
At 30ft, there should be no heat-wave problems and definitely no
atmospheric extinction or "blue scattering" caused by oxygen
molecules. I think possibly another reason for this is dynamic range
of CCDs. With macro shots, you can control the lighting to maximize
it, but you generally can't with long distance shots so you end up
with blocky highlights (still!) residual chromatic aberration, etc,
and both serve to kill details. What people generally don't
understand about chromatic aberration is that it isn't just an
"light-dark" edge problem; The defocussed blue and red light is
suffused over the entire image, supressing contrast.
-Rich

In article ,
RichA wrote:
On Sat, 01 Jan 2005 04:18:15 GMT, "Ken" wrote:


"RichA" wrote in message news
Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.

Besides the atmospheric obscurants inherent in any image taken over long distances the simple
fact remains that digital cameras still have a long way to go with regards to sensor and image
resolution. Objects that are small in an image are represented my just a few pixels and you
cannot get a lot of sharp detail when you have so few pixels to work with.

A fascinating project that is being worked on to produce Giga-Pixel images can be found at
the link below.

http://www.scienceblog.com/community/article4901.html


But it's using a conventional film camera, big plates and it's
converted to digital via a scanner.
I thought it was something like this:

http://www.cfht.hawaii.edu/HawaiianStarlight/

A true, 338 megapixel camera set-up.

There are several Gigipixel image projects being discussed at various places on the 'net.
One can be found at http://tawbaware.com ; another one is being done at a University
in, IIRC, Copenhagen.

John Francis wrote:
In article ,
RichA wrote:
On Sat, 01 Jan 2005 04:18:15 GMT, "Ken" wrote:


"RichA" wrote in message
news Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.

Besides the atmospheric obscurants inherent in any image taken over
long distances the simple fact remains that digital cameras still
have a long way to go with regards to sensor and image resolution.
Objects that are small in an image are represented my just a few
pixels and you cannot get a lot of sharp detail when you have so
few pixels to work with.

A fascinating project that is being worked on to produce Giga-Pixel
images can be found at the link below.

http://www.scienceblog.com/community/article4901.html


But it's using a conventional film camera, big plates and it's
converted to digital via a scanner.
I thought it was something like this:

http://www.cfht.hawaii.edu/HawaiianStarlight/

A true, 338 megapixel camera set-up.

There are several Gigipixel image projects being discussed at various
places on the 'net.
One can be found at http://tawbaware.com ; another one is being done
at a University
in, IIRC, Copenhagen.

Delft, too.

RichA wrote:

Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
It's got to be some kind of optical illusion
because lenses (I believe) are optimized for
infinity imaging. But, case in point;
When a friend was looking for a digital,
I showed him two shots from mine, one a landscape,
the other a macro. The landscape didn't impress
him technically (sharpness, etc) but the macro convinced
him to get the camera.

Macro shots in particular show fine detail to a degree that we don't commonly
see, so when we do see it, it is a fresh and often amazing experience. As a
macro shot (typicaly 1:1) is of detail of an object the size of the image
sensor, it is much finer than our daily experience. So the shot is perceived to
be highly detailed.

On a 'distant shot' there is less specific detail to look at so we don't 'see'
the sharpnees in it.
Atmospherics (convection, particulates) also soften the image a little to a lot,
conditions depending.

Cheers,
Alan

--
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-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: there's no such thing as a FreeLunch.

"Ryadia" wrote in message
...

"RichA" wrote in message
news
Ever notice how a long distance shot doesn't
ever look as sharp as a close-up shot?
SNIP

Interesting observation...
I just decided to play around with panorama stich on my 20D.
I also took the same shots with a GWS Fuji 120 roll film, pano
camera. I don't think I'll be converting from film to digital for
Panos just yet! It seems taht the further away you get, the less
detail is recorded.

That has to do with the absolute resolution limit a sensor poses on
fine detail. The sensor cannot reliably resolve projected detail
that's smaller than 2 pixels. Landscapes, or any subject at a distance
for that matter, will result in a very small magnification factor and
thus collide with the limitations of regularly sampled imaging. The
only solution (within the scope of this forum) is a higher resolution
sensor that still looks sharp at the intended output magnification (or
one can output at a smaller size). Stitching panoramas will
effectively simulate a larger sensor, thus requiring less output
magnification, but it has other limitations.

Bart