My 2cents are- look to the enlarger first, and then development, camera last. Rule out each in turn. ie the enlarger is easy to test, rule it out, and you know its development, or camera. Rule out the development, that leaves the camera. try a different camera and lens, rinse, repeat.
My bet is the enlarger.
Try mixing your dev with distilled water.
When you are ready to process , try to think you are sitting in your car with one hand on top of the wheel and one hand at the bottom. Turn the wheel to change the position of the hands , you will notice a distinct twisting motion.
the first 15 seconds of development is important to get the chems to all areas of a light nuetral grey of either skys or nuetral grey backgrounds, unfortunately if this is not immediate we get uneven grey tones and I think this is definately the problem with the negs you are showing.
If it was a lens issue either in the camera or enlarger ie lens falloff the problem would be on all sides and would manifest itself as a darkening on the corners , not lightening.
Originally Posted by jmal
I already use distilled water for all of my chemicals. My agitation method also involves a twist as well as inversion, very similar to what you describe. I will really concentrate on beginning the agitaton as quickly as possible and continuing it a little longer initially. Hopefully this helps. Also, I can see how light fall off in my camera lens would create darker edges, but wouldn't fall off in the enlarger lens create lighter edges? However, I do agree that it would be more uniform--a least I would think.
As for the conditions, it was a moderately sunny day and the sky appeared to be a consistent light blue. Around 1 o'clock. I don't remember exactly where the sun was at, though. As the problem occurs on both sides of the print, I'm not sure it has to do with the location of the sun. I could be wrong; light behaves in strange ways. The shot was taken in the Flint Hills of Kansas, so there is not much else around to cast obvious shadows. That's about all I can think of in terms of the conditions.
Last edited by jmal; 05-24-2007 at 10:16 AM. Click to view previous post history.
I think the most probable cause is uneven projection of the enlarger.
You could try to print a paper with no negative with an exposition time enough to print a middle gray (more or less) an look the result if grey is uniform or not.
you would really see the fall off on the easel and if you take out the neg and just print to a nuetral grey you will see immediately if it is the enlarger. Prepmiro is right it would be very obvious if this is the cause.
you are correct the falloff would lighten the edges but this really looks like a familiar film dev problem. critical in the first 15 secs.
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Well, since we're throwing out SWAGs here. Here's mine.
Camera has a vertical travel shutter---vignetting would appear at T &B of frame. Not sides.-----most unlikely.
Lens vignetting---maybe, w/parralel edges---not likely.
Enlarger---vignetting w/parralel edges---not likely.
Processing, edge density, agitation. IMO most likely.
The distribution of grays in the sky seem to be reflected on
Originally Posted by jmal
the ground. Notice the light areas and how in the sky and on
ground they define symmetric dark areas. Perhaps some very
unique quality of light and reflectance of subject. All your
landscapes turn out the same? Dan
Possibly flare from the side lighting. Were you using a lens shade?
Could be sun spots.
Another thread, just posted today by Andrew with more severe but similar problem.
Grey Cards, Grey Cards, Grey Cards. process, process , process.
the agitation and water content adjustments will solve unevendevelopment but it takes patience and persistance to eliminate the problems.