[Leica] 0.7 aperture lenses on digital sensor question

[mail at gpsy.com (Karen Nakamura)]

At 10:15 AM +0100 05.3.18, animal wrote:
>Hi i would like to know why large aperture lenses can be used 
>succesfully on a variety of sensing systems like x ray machines and 
>telescopes but could not be used in a camera.
>One can mount the array as close as one would like to the lens surely?

Simon - my guess is chromatic aberration. Most x-ray machines and 
telescopes operate on only a very small bandwidth. Thus, it's easy to 
filter out everything that you don't want.

A lot of the difficulty in designing good lenses including the use of 
expensive low-dispersion and  anomalous dispersion glass is to try to 
make a perfect apochromatic lens.

If only we'd stuck to single-wavelenth b&w photography.

Karen Nakamura
http://www.photoethnography.com/ClassicCameras/
http://www.photoethnography.com/blog/

--