streaks and mottling in film developmentgreenspun.com : LUSENET : Large format photography : One Thread
I have been having constant problems developing myTri-X film- It seems that my subject matter seems to be part of the problem. It is landscape sky/water on grey overcast and foggy days. I have been shooting 5x7 and now 8x10 developing with jobo processing in a lab. The film is usually streaked in vertical stripes if you are looking at the film horizontally. I started out with xtol developer and moved on to HC110 "F" to have an increased development time. Then I switched to Rodinol 1:50 for a preferred grain shape. I have had the jobo placed on an angle to supposedly diminish the "bromide drag". Sometimes the film is fine and other times it is streaked. The film has been sent to Kodak, and the best suggestion they had was to place the jobo on an angle. I tried another lab and still have bad results. I switched to Plus-X film and have the same problem. Whatever information you may have on this matter would be greatly appreciated. Joni
-- joni sternbach (firstname.lastname@example.org), April 03, 2002
Have you tried tray processing? Streaks can be caused by reels and/or film dev. holders. Sure, tray processing is boring. But if your tray technique is consistant you should be OK. Then again I process my 4x5 b & w in a Unicolor print (yes print) drum for years now and have never had a problem.
Try tray processing for a test anyway.
Regards and good light,
-- Steve Feldman (email@example.com), April 03, 2002.
Are you prewetting the film with water at the same temperature as the developer?
Is the Jobo reversing the rotation every few cycles?
I would think that the streaks and unevenness are most likely coming at the beginning development cycle.
-- Bob Eskridge (firstname.lastname@example.org), April 03, 2002.
Placing the JOBO at an angle is asking for trouble in my opinion. They take great care to warn you as a consumer that the tanks are designed to be operated perfectly level hence the instructions to use a level on the unit before processing. In situations like these, the best you can hope to do is eliminate one variable in the equation at a time until you have solved the equation. Here is a listing of what I would evaluate and then check off: *Fresh chemistry and film. *Correct volumes for processing. *Nominal light leaks in the bellows. Go in a dark room and a small flashlight and shine it into the inside of the bellows and see if you have leaks. *Light leaks in the film holders. * Light leaks during film loading.
I am inclined to believe that since you having similar problems at a lab, that it is some form of light leaking. Try processing an unexposed sheet of film for a clear result(film base plus fog) in your JOBO that is pefrectly level. Why Kodak is telling you to tilt the unit is beyond me. Good Luck and let us know what you find out.
-- Michael Kadillak (email@example.com), April 03, 2002.
Is the film being developed on the Jobo in their "Expert Film Drums" or in print drums? The first will work beautifully, the print drums will fail dismally in most cases.
-- Carl Weese (firstname.lastname@example.org), April 03, 2002.
When I first switched from 4x5 to 8x10 processing in my Unicolor drum I used the same amount of developer solution - about 90 ml or so. The results with 8x10 were horrible and just about everyone suggested that my volume of developer solution wasn't enough. I pretty much trippled the volume - 250 ml and everything was great once again.
It sounds to me like you might use - or more correctly the lab might use - too little developer solution as well.
I should say that with my much simpler Unicolor roller and drum I get excellent, even development and you might want to look into that.
-- David Grandy (email@example.com), April 03, 2002.
I had what sounds like a similar problem. It was remedied once I used a higher volume of developer. 600ml in the 2500 series tank.
-- Jim Kish (firstname.lastname@example.org), April 03, 2002.
I agree with the respondents that talk about inedaquate developer volumes in the drums. What perplexes me is why did Joni get the same results after taking the same film to a commercial lab? Something is going on here that supercedes the developer volume quick fix.
Is it possible that the film was bad? Static electricity?
-- Michael Kadillak (email@example.com), April 03, 2002.
Thanks everyone for your quick response. Just to clear things up, all the film has been processed in the lab from the beginning. Since the lab I used wasn't able to solve the problem I went to a different lab that used the 3 1/2 gallon tank w/nitrogen bursts that produced mottling and their job results were streaked. I think that the amount of solution might be the solution. The reason is the last time (and only time) I got perfect results the lab used full 1/2 capacity of liquid. They told me that they could not do that again because the weight was too much for the jobo motor. I am thinkiong that perhaps the best next try would be to roll the film with the same amount of solution by hand. Does anyone know if extended development times has any impact on mottling or streaking?
-- joni sternbach (firstname.lastname@example.org), April 03, 2002.
When I first used my 3000 drums, I was getting streaks as well. It turned out that I was placing the film in the tubes backwards. That is, I placed the emulsion side of the film facing outside toward tube. This put the emulsion up against the tube walls causing streaks because the chemistry could not flow evenly over the surface of the emulsion.
-- Stephen Willard (email@example.com), April 03, 2002.
Please don't discount the possibility of light leaks somewhere in your camera. Put a flashlight inside the camera (on),extend your bellows all the way out, put a film holder in the back and make sure your shutter is closed. Sit in complet dark for a few minutes. Even tiny light leaks will materialize.
-- Paul Mongillo (firstname.lastname@example.org), April 04, 2002.