View Full Version : Fall off with wide angle lens
I have a used Calumet view camera, Series 400, with a bellows draw of 10", (meas ured from film plane to lens. I don't know if this is the correct way of measuri ng.) My only lens is a CaltarII-N 90 mm, f:6.8. My prints are darker toward the middle and lighter around the outsides of the pr int. Is this what is known as falloff? Is there anything that can be done about it? I'll appreciate any help I can get. I'm just getting started in large format & f ind it rather frustrating. Joe Stanek
What you are seeing is light falloff as you suspect. Three ways around it. Fir st, get a center filter(Calumet can give you a lot of info on these). Second, w ork in the darkroom with judicious dodging and/or burning to even things out. T hird, shoot only scenes with very dark edges, such as in grottoes and caves. For most of us the third option doesn't work too well though. But try shooting at f/22 or so and a lot of the falloff will even out, tho maybe not enough for some subjects.
What you have is falloff, but I don't think it is from your camera lens. You say the prints are darker in the center and lighter around the outsides of the prin t. If you have falloff from the camera lens it should be the opposite. The print s should get darker at the outer edges because the negative would be thin at the edges. What does your negative look like? I think your problem is in your dark room. It might be from the enlarger lens you are using. If the focal length of y our enlarger lens is too short you will get the results that you described. Ther e is another possibility is if you are using a condenser enlarger. If the conden sers are adjustable they may not be set properly for the lens you are using. Goo d Luck.
I think you should look at your film processing techniques, also. Could be that you are not getting even agitation....more on the edges than in the center of t he film. Frank
I agree with Frank (above). I had the same problem when attempting to use a day light tank with sheet film. What are your processing techniques? I finally mad e myself some developing tubes with pvc and they are working very well. Erik Ryberg
Powered by vBulletin® Version 4.2.1 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.