Bromide drag?greenspun.com : LUSENET : Large format photography : One Thread
Thanks to those of you that suggested I used constant agitation when using the Stoekler formula to develop my B&W sheet and rollfilm - this certainly got rid of the "streamers" nr the edges of the film.
However, one thing remains as a constant - banding in large areas of even density like skies. Not every sheet is affected, not even every frame in a strip of roll film is affected, but I cant stop this phenomenon from happening.
When it occurs (and it occurs with annoying regularity) it looks like banding affecting skies BUT it seems to stop a little way into the "busier" areas of the film. Most of the negs that are affected also show some tonal bleed into the film rebate adjacent to the banded areas. In fact, on roll film the sky part of the neg looks like it has an echo/outline, as if there has been a double exposure (but I know that there hasn't).
I've tried different film/dev combos (eg Agfapan 100, Delta 100, ID11 at 1+1 and 1+3) but still the banding appears. I've tried agitating drums by hand: 10secs at the head of each minute, 5 secs every 30 secs, and also a unicolor drum on a reversing base, to no avail.
-- Neil Miller (email@example.com), April 05, 2002
Are you sure it's not a fixing problem?
-- Chad Jarvis (firstname.lastname@example.org), April 05, 2002.
Hi Chad - I'm pretty sure it isn't a fixer problem. After dumping the dev I use a weak acid stop bath followed by fresh fix (Ilford Hypam) for at least the time stated on the packaging. I then fill the drum/tank with water, dump it, fill it and follow Kodaks archival sequence for washing.
As variations to the above I have used plain water stop and have also used a running water wash. I never had this problem where I used to live, its only appeared during the past year!
-- Neil Miller (email@example.com), April 05, 2002.
One way to find out; after the stop bath remove the film from the drum, fix and HCA it in a tray.
-- John Hicks (firstname.lastname@example.org), April 05, 2002.
If it has only appeared during the last year - and not the place you used to live...???
Maybe the water is different...use destilled water for developer, stop and and fix...
-- Per Volquartz (email@example.com), April 06, 2002.
I've had problems with this in the jobo print drums I use to process 7x17 negatives with Pyrocat HD. Try tilting the drum back and forth about every 2 minutes in a direction perpendicular to the drum rotation direction for about 10-15 seconds during development. This solved the problem for me. Check out www.unblinkingeye.com on the Pyrocat-HD page. I wrote a little addition to the article about this specific problem, which may help.
-- clay harmon (firstname.lastname@example.org), April 06, 2002.