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pkr1979
9-Oct-2020, 00:39
Hi all,

The answer to this might be obvious, however... it is a mystery to me. Will negative films like FP4, TMAX100 or TMAX400 with long straight line curves and fairly high density ranges keep those characteristics when reversal developed?

I would assume the way a film is developed (reversal or not) will affect that?

Cheers
Peter

ic-racer
9-Oct-2020, 15:11
That is a good question. Do you have a way to make H&D curves yourself?

pkr1979
10-Oct-2020, 05:54
Nope - I have no idea how to do that... or what I need to do that.

Lou Baleur
12-Oct-2020, 13:48
reversal uses high energy developers and will make that straight line section much shorter for stops of exposure--contrast increases tremendously and the straight line portion from clear to black is much much compressed. So there is really no way to compensate with development for contrast range, if that is your intention.

koraks
12-Oct-2020, 22:18
In reversal processing, you can certainly influence first development, fogging and second development to alter the film curve. One obvious application is to have the choice between making high vs low contrast positives with the same film. It takes a bit of experimentation to get what you want, but it can certainly be done.

pkr1979
13-Oct-2020, 05:39
Thanks. I'm looking into how to make carbon prints from a positive. So, it seems like I want the positives to dense and contrasty... as far as I can figure out. Which I actually think many of them are.

Raghu Kuvempunagar
14-Oct-2020, 18:53
Thanks. I'm looking into how to make carbon prints from a positive. So, it seems like I want the positives to dense and contrasty... as far as I can figure out. Which I actually think many of them are.

Well-made slides have very good contrast and DMax as you are using the full range of densities that the film is offering you. DMin can vary depending on the film and how effective the reversal process was in producing clear highlights. To give an example, DR5 claims a DMax of 4.29 for Ilford Delta 100 and a dynamic range of ~10 stops.