Re: Another camera question

[inet@intellisys.net (brian whatcott)]

At 05:36 PM 4/2/97 EST, Paul Camp wrote:
> Some of them use a contrast sensor, a light sensitive surface in the 
> image plane that seeks maximum contrast in the image...
> Paul J. Camp

I'm with Paul on this one.
To put it another way, the maximal spatial frequency component in the image 
area of interest is attenuated.

 Which segues into another possibility for a discard camera:
with a translucent screen or perhaps greaseproof paper in the image plane, 
and a low power laser expanded onto a 35 mm transparency
at the focal plane distance in front of the camera lens, this is a low cost 
demonstration of spatial fourier transforms.

 Vertical bars at the forward plane transform to a pair of spots in the
horizontal direction of the image plane and so on.
 An optical atlas of transforms would be a handy reference here. 

A further step in sophistication is to provide an optical filter at the 
image plane ( central hole = low pass ) and use another lens to transform 
the filtered image back to its original form where the effect of high pass 
or low pass filters can be observed.

Regards
brian whatcott <inet@intellisys.net>
Altus OK