graywolf
Well-known
I think it might be a good idea to do some variation at an exposure series: EV-values: -3, -2, -1, 0, +1, +2, +3
And a developemt for the standard ISO value of 100.
But before doing this I should get/build/modify a lens shape for it to prevent stray light...
If you keep the light over your shoulder (behind you) for the tests there should be no need for a lens shade.
Yes, as to the EV values, but change the shutter speed as you want to keep the f/stop the same so you are not getting unintended lens performance changes. This is standard troubleshooting procedure, only change one thing at a time until you find what is causing the problem. Sometimes there are more than one problem, so you fix the one you found and go through the whole procedure again until you find the next problem. Eventually you have found and fixed all the problems. OR, you decide it ain't worth all that effort, and toss it in the trash (grin).
Some people have seen the same problem again and again, so they just go ahead and fix that problem. They have another problem, when they have a problem they never saw before, they do not have any idea what to do. With complex systems they are usually wrong and just make things worse. Just checking one thing at a time will always allow you to find what is wrong, no matter how complex a system you are working on.
Dwig
Well-known
...
He is trying to figure out whether he has a camera problem, a film problem, or a processing problem. Fixing it does not help with that.
Actually, there is a one size fits all processing. That is the correct processing for the film being used. Color film proves that...
One, fixing it in PS can help as it can confirm whether the exposure is reasonably close and is a proper step in the experiment if the final images with also be scanned and digitally printed.
The negative should be scanned so that some of the "clear" film between images is present in the scan. The image can then be adjusted so that the "clear" portion is just barely true black. If the shadow detail is then properly placed the exposure is correct. If shadow detail is missing it underexposed and if its noticeably too light the neg is overexposed. After exposure is determined, processing should be adjusted to place the highlights correctly.
I still contend that there is absolutely no such thing as one-size-fits-all processing, expecially when working with lenses of varying ages. Color film is crippled/limited by the inability to do such adjustment. The lack of adjustment ability with color is in no way proof that it should be used with B&&W.