Mottle-Free development of LF C-41 Films

hey all,

I have a simple, yet obtrusive problem that many of you have probably wondered about. Well, my fruitless searches here and on LFF to find an answer have gone un "fruited" , so, hence my question:

I know its "possible" to run c-41 at a lower temperature that 100deg F, but its not recommended. Being that the "N(normal)" time is 3:15, I have wondered if running a cooler, slower process would affect overall color balance in the end, along with general density of the resulting negative.

so

1. Could I run Kodak's chems at a lower, slower(time-wise) method for 8x10 development(in a rotary tank, 1 sheet, jobo 2551 tank)? The new Rollei digibase c-41 chems(supposedly made by Fuji) have instructions on running the developer at a lower temperature, and give recommended times for such(in the downloadable .pdf here: http://www.macodirect.de/download/C4...tionManual.pdf

2. How does this differ from running Kodak's chemistry(supposedly the same???) at the lower temperature? Now, since I'm a "low volume" user, I was planning on purchasing the SM line of chems(5L), and just mixing those up to use, since I'll be developing in a single run over about 2-3 days or so.

3. My main problem is this: I'm going to be shooting 30-40 sheets of 8x10 color film, along with 40-50shts of 4x5 while assisting this summer, and since I might not have a chance to return to where I'm going(Iceland) any time soon(if ever), I don't want to screw this up at all. I'd rather get the best negatives I can(why I want to self-process vs. taking it to a lab), and time really isn't an issue(hence doing it myself).

4. Any thoughts or comments?

thanks

-Dan
http://www.macodirect.de/images/Vorschau_Manual.jpg

I have run processes at 68F and 75F using authentic C41 chemistry. This included development times up to 20 minutes and also soaks in water after development to try to bring up the bottom layer which was pretty much lacking in all tests. Nothing worked for me. So, either this is a "new" formulation, or it is not going to work properly.

I do endorse making a standard reference to whatever process you select, using a color chart, and then comparing both.

Best of luck.

PE

Greg Davis said:

All I can recommend is to shoot two identical shots and develop one at 100° F and the other at the lower temperature and see what differences come out. If you have the means to make a contact sheet you will be better able to visually compare. It would be even better if you include a gray card in each shot for color balance and exposure evaluation.

A Jobo 2830 drum will allow you to process two 8x10 sheets at once so you don't have as much work to do. The extension (2870?) will double that to four sheets.

Click to expand...

Greg,

I've not run 8x10" C-41 yet, but using a Jobo 2830 drum for B&W resulted in vertical streaks (with film in horizontal orientation) of uneven development. The Jobo 3005 drum works fine (again for black & white).

Tom

Greg Davis said:

I'm sorry to hear that, Tom. I use the 3006 for 4x5, but the 2830 for 8x10. My experience is with Xtol and D-76 and have not gotten any streaks. I have heard that other developers, especially staining ones, cause streaks. I have not tried C-41 yet, but plan to in the future if I can get the temperature control figured out since I do not have a processing machine, just drums and a roller base.

Click to expand...

I noticed the streaks on Pyrocat-HD developed negatives. Attempts with Ilfotec HC 1+49 may have been OK; I'd have to check.

Tom

I just found a lab in NY that has a "proprietary process" for mottle free development, I guess they wouldn't be willing to share their secrets

Page 2, under "sp- c-41" prices are about 2x the normal rate though....

http://ltiny.com/lti_pricelist.pdf


they even show film sizes up to 16x20 !!! I'm starting to wonder if this is dip-n-dunk, or done in a jobo tank...

-Dan

that's what I was planning on using, if I can find someone that I can rent one from

-Dan