uneven development.

pmu · Feb 27, 2007

Hi, I don't know how I have suddenly developed this problem because I think I do everything the same like before -- and I didn't use to have this problem.

I have 2x 35mm reel paterson tank and I have been lately getting uneven development to the film on the top reel. Uneven underdevelopment close to the perforation (that side which is nearest to the top of the tank). I think it can't be too little agitation because yesterday I overdid that -- still uneven. Also there is enough liquid to cover the whole reel. Or maybe too much of liquid and the dev. does not change enough during the agitation? Well, couple of nights ago I used exactly 600 ml, yesterday 650ml and the same result - the top reel on one side unevenly underdeveloped.

I dunno, I have developed around 100 rolls with my usual routine with no problems and no I get this kind of basic problem and can't figure out where the problem is.

I agitate so that I turn the tank upside down 3-4 times (total 10 seconds) in every 1 or 2 minutes (depends...). My usual routine that is.

Ideas?

EDIT: This uneven dev. is not on the whole film... maybe 60% of the film has that light under.dev streak.

Konical · Feb 27, 2007

Good Morning, PMU,

One reason I stopped using Paterson tanks and reels back in the 1970's is the problem of uneven development near the film edges. Actually, I never had a problem with 35mm, but 120, with its narrower rebate, sometimes came out uneven. In addition to inverting the tank, you might also try spinning the reels with the device intended for that purpose. To eliminate the problem completely, switch to SS.

Konical

H. Severiens · Feb 27, 2007

pmu said:
I agitate so that I turn the tank upside down 3-4 times (total 10 seconds) in every 1 or 2 minutes (depends...). My usual routine that is.

Ideas?

EDIT: This uneven dev. is not on the whole film... maybe 60% of the film has that light under.dev streak.

It could be a problem with to much agitation. The larger paterson tanks are very prone to that. Try a film with just two inversions per minute and very gentle movements.

Huub

fhovie · Feb 27, 2007

I have to be really careful when doing 8 rolls of 120 at a time. 2.5 Liters of developer has a lot of force even with "gentle" inversions. I have a small SS tank that I can shake like crazy and no problems but the more fluid in the tank, the more inertia when aggitating. Plastic reels have thicker lands and can be more suseptable to uneven swirling of fluid. I would say slow your inversions down, do fewer and add a gentle spin to go with the inversions. I Have used a patterson tank for many years but it only does 1 120 roll at a time and 2 35mm rolls at a time. Not as much fluid and not as risky. It is the Big Jobo that gets unwieldy with up to 3 liters for 18 sheets of 4x5.

KenM · Feb 27, 2007

I would suggest that you try and determine if the 'unevenness' is either surge marks, or indeed unevenness. If you're getting surge marks, reduce agitation - if it's unevenness, increase agitation since you may not be agitating enough to replace the spent developer. Within reason, of course

pmu · Feb 27, 2007

Ok, here we go --> Dead Link Removed

That is from a film I developed yesterday. 620 ml of liquid and way more agitation than usual. See that uneven clear line... So this happens only to the film in the top reel on the filmside closer to the top of the tank.

Hey, now I remember that I got this same thing last time when I developed 120 film. 1/6 of the top side was underdeveloped with a same kind of clear line... Dead Link Removed

pmu · Feb 28, 2007

pmu said:
Ok, here we go --> Dead Link Removed
Dead Link Removed

hey anyone, ideas? Could it be somekind of weird light leak in the dev.can causing this? I just measured and 600ml of liquid was enough to cover both reels.

jlehmus · Feb 28, 2007

Is the 60% portion with the streak in either end of the film, or is it "in cycles" all through the film?

Does you dev look foamy when you pour it out from the tank after development?

I suspect this problem still has to do with the amount of the dev liquid and a portion of it getting foamy because of the agitation by inverting. My suggestion would be to fill the dev tank right to the brim and try agitating by rotating the reels with the "little funny rod" that comes with those Paterson tanks.

Any kind of light leaks would produce dark faults on the negative, not light ones.

pmu · Feb 28, 2007

jlehmus said:
Is the 60% portion with the streak in either end of the film, or is it "in cycles" all through the film?

Actually I looked closer and it is all the way - not just 60%. I usually shoot in pretty low-light situations and I didn't see that underdev clearly enough. But the last roll was shot in "normal" lightning and it had that streak all the way.

Does you dev look foamy when you pour it out from the tank after development?

I suspect this problem still has to do with the amount of the dev liquid and a portion of it getting foamy because of the agitation by inverting. My suggestion would be to fill the dev tank right to the brim and try agitating by rotating the reels with the "little funny rod" that comes with those Paterson tanks.

I haven't noticed any foaming, but I'll keep an eye on that next time.

It might be that foaming thing that causes this (even if I haven't noticed any foaming ) but could the problem still be in the dev. tank? I have 1 paterson 4 tank with one paterson reel and one AP tank with 2 reels. Those parts have been mixed and could it be somehow possible that for example AP tank + paterson top + 1 AP reel + 1 paterson reel combination does not work 100% together? I noticed that the AP tank is about 1½ cm taller that the paterson one so there is enough space for the liquid to move even if filled with 650 ml.

dr5chrome · Feb 28, 2007

the 1st image isnt a development issue. You have a fog coming from somewhere. My guess would be the camera, The 1st image. The 2nd image seems like a combination of both but more development.

dw

www.dr5.com

reub2000 · Feb 28, 2007

dr5chrome said:
the 1st image isnt a development issue. You have a fog coming from somewhere. My guess would be the camera, The 1st image. The 2nd image seems like a combination of both but more development.

dw

www.dr5.com

Fogging in the camera would create more density on parts of the film, and wouldn't discriminate between rolls that are on the top and bottom of the tank.

Also, spray your negatives with canned air before scanning.

jlehmus · Feb 28, 2007

My guess still is that the uppermost spiral isn't completely immersed in the developer during the development.

Possible causes:
- excessive foaming due to agitation or some other reason
- insufficient amount of developer
- the spirals have some leeway in the tank and somehow the uppermost is able to rise over the surface of the developer

pmu · Feb 28, 2007

Maybe I need to take couple of test rolls to some old crappy negative and do a thorough test. Or maybe just start using my Jobo tank instead...

The fault can't be in the camera, because I have been getting this same results with 3 different cameras.

pmu · Feb 28, 2007

reub2000 said:
Also, spray your negatives with canned air before scanning.

no way, that dust is supposed to be in that particular image...I tried to increase the amount of dust

Loren Sattler · Feb 28, 2007

To eliminate the possible light leak idea, try developing in the tank as usual, but in total darkness in the room. This would identify that potential problem.

Have you changed film? Some films tend to develop more or less evenly depending upon their toe characteristics.

For several years, I fought uneven development with 120 film in a single roll stainless steel tank. I thought I was helping the uneven development with less agitation. I got to the point of just swirling the tank slightly at 30 second intervals. Someone on a forum suggested that insufficient agitation caused the uneven development, and I concur.

Read Kodak's typical agitation instructions (page 4 of 12):http://www.kodak.com/global/en/professional/support/techPubs/f9/f9.pdf

These instructions call for "5-7 vigorous inversions every 30 seconds". I switched to this method and rarely see any uneven development with Tri-x 400 and Plus-x films. Contrast increases. My standard development time (for a condensor enlarger) is about 85% of the suggested time.

Hope this helps.

Huub S · Mar 1, 2007

pmu said:
hey anyone, ideas? Could it be somekind of weird light leak in the dev.can causing this? I just measured and 600ml of liquid was enough to cover both reels.

I see how the uneven development follows the holes in the film very nicely. When i had the same effect, reduction of the agitation solved the problem. The Paterson tank is constructed in such a way that, when you inverse the tank, a lot of developer goes into the light trap, causing more turbulence on the top real than on the bottom real. Give it an other try and follow my earlier suggestion: move the tank very gentle and reduce the agition to 2 times a minute.
My second thought: 600 ml is enough for two 35 mm films and 500 ml is the amount that should be used for 1 or 2 120 films. But the reals on the Paterson reels have the nasty habit to move upward on their centre column, especially when you agitate to vigouriously, after which the top of the film will stay above the developer. A long time ago you could buy special clips to prevent this, but using 600 ml on 120 should also solve this problem.

Huub

pmu · Mar 1, 2007

I think I finally solved this mystery;

The tank is AP tank. That middle "rod" (or what is it called?) -- that where you put those spirals, you know -- that is poorly designed in AP tanks. I just "simulated" the agitation and noticed that if I turn the tank totally upside down that "rod" sometimes did not go to the bottom of the tank when I had finished the agitation... I don't know how to explain this, but it landed so that it was about ½-1 cm too high...that rod is poorly designed. And if that would happen during developing I would get these kind of unevenly developed negatives in that upper reel. I think that this has to be the problem because I haven't use this AP tank earlier -- I used little smaller 2 reel paterson tank instead and never had these problems because that rod is designed better (used same kind of agitation style and everything).

Lee L · Mar 1, 2007

The AP tank is designed with a center post that can be used to agitate the film by spinning with another rod through the central funnel hole. The bottom of the central post is formed in a "wave" pattern that rides over three raised ridges on the bottom of the tank, which forces a gentle lift and fall of the reels as you spin them. This is an intentional design to introduce proper agitation if you spin with the supplied post.

You can prevent your problem by making sure you have enough developer to cover both reels with the center posted lifted that 3-4mm. There is also a white C-shaped clip that goes over the central post to keep the film reels forced down far enough to work properly. You should use it, or find a replacement if you've lost it.

Look at the bottom of the tank. It recommends 375 ml for 1 reel of 35mm and 650 ml for two reels of 35mm, so you were about 30ml shy of a full load.

Lee

pmu · Mar 2, 2007

Lee L said:
Look at the bottom of the tank. It recommends 375 ml for 1 reel of 35mm and 650 ml for two reels of 35mm, so you were about 30ml shy of a full load.

Lee

Oh boy, do I feel stupid right now!

Lee L · Mar 2, 2007

pmu said:
Oh boy, do I feel stupid right now!

You should be feeling smarter, or at least better informed, now, and confident that you can get back to processing without getting those pesky clear film edges. "Live and learn" is much better than endlessly repeating your mistakes.

Every decent plastic tank I've used has the required chemistry amounts stamped on the bottom or on a label on the side, and I use them seldom enough that I always have to double check by reading the tank.

Lee

uneven development.

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