Sam says (Contrast and Realists)

[P3D Dr. George A. Themelis <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

>Sam, that's for you and thanks for bringing up those interesting topics!
    
Thanks for the encouragment!
   
>>If so, is it not possible to design a filter to
>>reduce contrast in high contrast lenses?
>>    
>Oh, yes!  It is actually called the "dirt and fog" filter! ;)  Seriously, I
>use it in my SLR for slide bar shots.  Any dirty/fogged filter will smear
>the light and reduce the contrast.  Some people think that a dirty filter
>reduces sharpness.  I think it has nothing to do with sharpness.  It only
>reduces the contrast by increasing the stray light, etc., as Sam
>described......But I still don't think that the Belplasca is sharper than 
>my 2.8!!!
  
I'll never argue against the quality of Realist lenses. Speaking of the 2.8,
this leads me to another example of a contrast problem. While I was shooting
in Asia with my Realist 2.8 a few years ago, I ran out of Kodachrome and had
to shoot with Velvia. What a disaster! The tropic sun made the scene real
contrasty, the film was too contrasty, and the darn lenses were too
contrasty! Lost a lot of good shots that trip. If only I'd brought my
Verascope! Incidently, I ended up selling my 2.8 and keeping my 3.5, because
my 3.5 lenses were actually sharper. It just goes to show you how lenses
differ from camera to camera, not just company to company.
    
I think any transluscent material such as oil or vaseline might affect
sharpness by altering the wavelength. I'm wondering if there's a solution
that will guarantee no loss of sharpness. For example, what if you had a
small LED "flash" a small amount of light on the film as it's in the camera
prior to exposure. An even better idea would be to use fibre optics, for you
could use diffuse light from the scene itself to give the proper color
temperature. Either way, you'd have the advantage of being selective as to
what subjects on that roll of film would require it. I'm sure with modern
technology the camera could even read whether a subject was too contrasty
and compensate with the appropriate amount of flashing. Maybe it's already
been done, although certainly not with a stereo camera.
    
One thing has never seemed to add up regarding modern slide film and lenses.
The lenses are more contrasty, so they made slide film more contrasty.
Where's the logic in this? I sure miss the old Agfachrome.

Sam
website: http://www.barint.on.ca/~sam/imn23d.htm
 
    
>    
>


------------------------------

End of PHOTO-3D Digest 1562
***************************
***************************
 Trouble? Send e-mail to 
 wier@xxxxxxxxxxxxxxx 
 To unsubscribe select one of the following,
 place it in the BODY of a message and send it to:
 listserv@xxxxxxxxxxxxxxx 
   unsubscribe photo-3d
   unsubscribe mc68hc11
   unsubscribe overland-trails
   unsubscribe icom
 ***************************