PDA

View Full Version : Unicolor drum problems(continued)



Michael Pry
6-Mar-2004, 06:28
I didn't include this in my original question but I will at this time:

The film is defenitly loaded with the emulsion towards the inside of the tube(I have done some really stupid stuff in the past so yes I never ruled that out)!

I did in fact on several sheets fix for two minutes in the tube and then two minutes outside the tube.

I did do a side to side agitation OFF the base at one minute intervals.

All these things considered I am befuddled! Thinking at great length on these I was wondering if there is a chemical contamination issue here? Could the old plastic be somewhat porus and holding a chemical that is tainting my chemistry and or film? I washed the insides with a citric type cleaner and even left them with water in overnight standing up on end. Maybe I need to try to use something to neutralize the inside of the drum? Vinegar? Any thoughts would be welcomed wholeheartedly.

Thank you

Leonard Robertson
6-Mar-2004, 07:53
Michael - I am following this thread very closely, since I am hoping within a few days (tomorrow with luck) to be developing 8X10 Arista in an 11X14 Unicolor drum with Pyrocat-HD. In other words I'll be doing exactly what you are doing. With 5X7 in an 8X10 drum, I do the sideways agitation and turning the drum end for end during the 5 minute presoak, not just during development. However, I believe you mention in your original post you have presoaked your film outside the drum and loaded wet, and still have the lines. Maybe your chemical contamination of the drum idea is possible. I have one 8X10 drum that is badly etched/discolored from color chemicals. I've been curious if it is still usable for B&W. I'll do a couple of 5X7 negs in it to see. But if your drums were contaminated with a different chemistry, I may not see the same problem you have. Do the inside of your drums look etched or anything to indicate contamination?

Doug_3727
6-Mar-2004, 08:16
Micheal, I again think your problem is more in the soaking of the film prior to developement. You are essentially doubling the time the film is in liquids. this has to be softening the film base to some degree. I would not rule out contamination but that would manifest itself in more than a localized area I would think. You would see wider effects from it. Have you tried one sheet without the presoak yet? I still think that is the root cause of your problem. One question not asked is how old is the HP4 your are using? If it is fresh try a sheet from a different batch to see if you get the same effect.

Good luck and keep us posted..

sanking
6-Mar-2004, 09:41
I am not sure how long people have been using paper drums to process film but it became fairly common about six or eight years ago for Pyro processing with Rollo Pyro, and some people did in fact complain of uneven development on the film that corresponded with the location of ribs. At the time I speculated that the problem was due to the fact that the ribs push the film slightly forward at the point of contact and this results in an accelerator of the developer as it passes over this point. In other words, the ribs cause a line of hot development because of greater developer agitation. This is the only theory that makes any sense for me regarding uneven development at the point of contact with the ribs. Some people quite using Pyro developers because of this problem and found that very dilute developers and extended development times eliminated the problem. I recall that Fred Newman once recommended D76 1:4 for development in tubes. But I personally have never experienced this problem with Pyrocat-HD, and I have developed a lot of FP4+ with the 2:2:100 dilution.

With short development times the unevenness caused by the laminar flow pattern builds up quickly, and unless arrested very early in processing by sideways agitation, results in an exponential increase in film density at the pont of contact. I would try a sheet of film with the following modification to your technique.

1. Use a more dilution solution, say 1:1:100. This should extend development time to about eight or nine minutes with FP4+. If this helps but does not eliminate the problem try a 1:1:200 dilution, but double the amount of developer and extend time.

2. Agitate first with sideways motion, not on the motor base, and then agitate briefly with sideways motion every 30 seconds.

You can also test Doug's theory that the cause of the streaks is the presoak by testing the extremes. That is, develop one sheet of film without any presoak at all, develop another with a five minute presoak adding about 1/2 spoon of an alkali such as sodium carbonate the presoak water. This would result in even greater softening of the emulsion and aggravate the problem if indeed it is caused by a softening of the emulsion in the presoak.

Jon_2416
6-Mar-2004, 11:35
Michael,

Have you tried a neg with another developer? My be worth it to see if you have the same problem.

I use my Unicolor for 4x5s and it works well after solving some problems. First I was using too little liquid and got uneven density--now I use 450ml for 1-4 negs. I put blank cleared negs in the other slots to keep the flow pattern consistent--in other words, there is always four sheets in the drum. Is it necessary? I don't know--but, it gives me piece of mind.

Ilford says in their instructions not to use a pre-wash, but If I remember correctly, someone asked their tech suppport and they said it was ok. I always use it--more to even out and slow the absorption of the developer--I think I can control my highlights better that way. That is also the official line at JOBO.

Also: a side note about random agitation. My counter is not flat where my motor sits, so If I do not put a spacer under one foot, the motor base rocks back and forth diagonally. I also have rubber bands around my tank to keep them from walking--if you adjust the bands so they are not in a flat plane, then as the drum rotate it ride up on them and rocks the drum--adding some randomness. Again, I don't know if it is necessary, or just me imaging things.

I do know, however, that if I shoot a flat wall with consistent light and process the negs in my drum, the negs are perfect in density according to my densitometer.

Try a different develper to rule out that variable.

Brian Ellis
6-Mar-2004, 16:07
Ilford recommends not using a presoak. You're using a five minute presoak with Ilford film. That might not be a good idea though whether it's contributing to the problem or not I don't know. Have you tried eliminating the presoak?

sanking
6-Mar-2004, 19:16
In attempting to find the cause of the type of problem being experienced by Mike I would not preclude any possibility and eliminating the presoak is certainly something that should be considered.

However, I am unaware of any information in the literature that shows that a presoak can do any harm, with the possible exception of developing film at temperatures of 85 degrees or more. Regarding Ilford's position, and if I am wrong about this I will certainly stand corrected, my understanding is that their recommendation to not presoak is based on the fact that it would invalidate their recommended development times, not because it might damage the film. Kodak does not recommend a presoak either, and for the same reason.

As for Jobo they recommend a five-minute presoak. They explained their reasons for this in 1998 in one of their Quarterly publications, available at http://www.jobo-usa.com/jq/jq9802.htm

I would also add that Job only recommends processing film in smooth wall tubes and drums, such as the Expert drums. In fact, I am fairly certain that at one point they offered for sale a special blanket to place inside one of their ribbed tubes to eliminate the exact problem we are discussing here.

I know many people who have experienced uneven development using print drums with ribbed walls, using a variety of different developers. But I know many others who are able to make perfect negatives with print drums. I personally have developed several hundred sheets of Ilford FP4+ film in drums with ribbed walls over the past six or eight years using several developers, including Pyrocat-HD. Which just proves that photography is as much alchemy as science.

John Kasaian
6-Mar-2004, 19:20
Michael,

If you're using the 11x14 drum, load only one sheet of 8x10, emulsion side in. The long (10") demension should fit under one side of the big V channel so the whole sheet is curved against the inside of the drum wall. It is easy to feel in the dark when you're loading the sheet of film. This is a Unicolor drum, right? I have tried using both a Western and Dev-tec in the past and found them both absurdly difficult to get even development.

You can do everything you'd need to do in the dark in the unicolor drum. I presoak Kodak films with distilled water in the drum, but not Ilford(or Ilford-oids, like Arista).

You do not have to take the film out of the tube to fix, it fixes just fine in the tube on the unicolor base unless you haven't fixed it long enough to remove the anti halation junk, in that case you can put it in a tray.

You do not have to take the drum off the base and rock it. The reversing action of the unicolor base takes care of that.

The 11x14 drum will only accept one sheet of 11x14 or 8x10, it cannot handle 4x5 0r 5x7.

The 8x10 paper(or print) drum can handle up to four 4x5, two 5x7, or one 8x10.

The 16x20 should handle four 8x10(I have only tried it with two sheets of 8x10 however, so I might stand being corrected!) or one 12x20.( I've never tried the 16x20 drum with 11x14 so I won't attempt a guess.)

I hope this helps.

tim atherton
6-Mar-2004, 19:47
"Regarding Ilford's position, and if I am wrong about this I will certainly stand corrected, my understanding is that their recommendation to not presoak is based on the fact that it would invalidate their recommended development times, not because it might damage the film."

Ilford says it removes the built in wetting agent on their films and claim this can lead to uneven development

sanking
6-Mar-2004, 21:26
Tim,

OK, I stand corrected.

However, I have also read that Ilford recommends a pre-soak with rotary processing. Do you know if they have any of this information available on a web site?

Sandy

tim atherton
6-Mar-2004, 21:50
Sandy,

I think that info came from a previous incarnation of the Ilford discussion list on their site... But I seem to recall their tech was sort of ambiguous about it - basically, we don't recomend it - but lots of people do it anyway for Jobo processing .... (partly, I think because, until Kodak actually did the whole series of tests for Xtol in rotory processors as well as "normal" processing, Jobo found the best way to give times for rotary processing was just to use the manufacturers recommended time + a 5min presoak). So Ilford doesn't recomend a presoak and doesn't provide times for rotary processing (neither does Kodak apart from for Xtol), but to get a simple recomended starting point for development, Jobo says use the manufactures (Ilford's) recomended times and pre-soak...

Leonard Robertson
7-Mar-2004, 09:19
To clarify something John Kasaian said about the number of sheets in Unicolor drums - the 11X14 drum will hold two 8X10 sheets or four 5X7 sheets (although some sort of spacer is needed to keep the 5X7s from overlapping, just as spacers are needed when doing four 4X5s in an 8X10 drum). There is plenty of room for four 8X10 sheets in a 16X20 drum, although again, spacers will be needed (and like John, I haven't actually developed four at a time, just dry loaded some scrap film). In theory, eight 5X7s can be loaded in a 16X20 drum, but six spacers will be needed. I suspect most people would find it easier to do two runs of four 5X7 sheets in 11X14 drums.

Al W
7-Mar-2004, 13:47
Why don't you try the Beseler print drum to eliminate the ribs? Sandy might be correct on the rib agitation theory. Pyro is very sensitive to currents in the solution during developing.

Michael Schiller
4-Jun-2004, 03:44
I had exactly the same problem using Ilford film (only I was using 4x5 film in an 8x10 drum). The marks were on the back side, almost as if the film was rubbing against the drum, it wasn't the anti-halation layer still there, it was miniture scratches. At the time I was using a 2 minute pre-soak, and after reading that Ilford doesn't recommend a pre-soak I tried developing some without the pre-soak, and the marks were gone! Yesterday after doing more reading, this time on Jobo's site, I tried developing some HP5 with a 5 minute presoak, and also had no problems, so I think the problem was from a too short pre-soak. I also noticed that when draining the pre-soak it was almost sudsy, like from a wetting agent, so as I was using Rodinal, I decided to use the pre-soak water to mix the Rodinal (in effect keeping the pre-wetting agent in the solution) and it worked great.

-Mike