from Paterson to stainless steel - agitation or equipment problem?

So far the forum has been a great help to me. I've never had a reason to start a post because the information always was already there. However, this time I need a little bit more help.

Years ago I obtained stainless steel reels to develop 135 and 120 film. Never used them because I was happy with all my Paterson stuff. But over the years I became more critical and found developing streaks in clear skies - even with pre-washing. After some research, I found out that the plastic Paterson reels are not spacious enough for the developer to work equally. Stainless steel reels might solve my problem, I thought.

I developed a 120 film like I always did, but this time in a plastic LPL tank and one 120 reel (only fits one reel).
Pre-wash 1 min.
Develop about 7 min, TMX in TMX developer 1+4, agitation two times every 30 secs.
Stop, fix and wash in the usual way.
During these steps my tank was always completely filled.

The result: over the length of the film the density is thicker than on the inside, so it developed faster on the top and bottom of the reel. What have I done wrong? I assume my agitation method is wrong with this tank/reel, but I'm not sure. Or is there something wrong with my equipment?

I dearly would like to know what other people think about this. Thanks in advance.

You say your tank was completely filled, if so, how did your solutions move around the tank during agitation? I have used stainless and Paterson tanks over the years but have always had lots of room in the tank apart from what the solution is taking up, in other words, I have never completely filled a tank and I suspect your problem with uneven development has to do with filling the tank to the brim! BTW, Patterson tanks work fine, if you are having problems they will be because of agitation mistakes.

Well, maybe I exaggerated a little. I leave some air in the tank, but not much. What you say makes sense, though.
I've never had this particular problem with Paterson.
Should I have another agitation method with different tanks/reels? Do you notice a mistake in my agitation? What is your method?

Not very much air is needed. Try being a little more vigorous with your agitation, and/or extend the time you agitate. For example, if you are doing 5 seconds, try 10 seconds. Be consistent, and only make one change at a time.
Agitation seems to be a very personal thing, at least based on what I've seen in the threads with agitation questions. What works great for one person, works not at all for someone else, so the key is to introduce a reasoned change in your routine and test.

charlemagne said:

I developed a 120 film like I always did, but this time in a plastic LPL tank and one 120 reel (only fits one reel).

Click to expand...

I'm not familiar with the LPL tank, but if it's one that normally uses a center core, and you didn't use a core, with the stainless reel, you'll get light leaks.

What you need to do is place your reel inside the tank, and place enough water in to just cover the reel(with the lid off so you can see it). Now pour the water into a measuring cup to see how much actual fluid it takes to develope. My guess is you have been over filling the tank even though you say there is air space in the tank.

What sort of movements are you using when agitating the tank? I ask because if the agitation pattern doesn't essentially cause the liquid to "tumble" it may be that you are essentially agitating the fluid at the top and bottom of the tank, while leaving the fluid at the centre relatively untouched.

In addition, your problems with the Paterson tanks may be due to the same issue - the Paterson tanks and reels work well for a huge number of people.

The way how I agitate my Paterson and LPL tank:

rotate ('tilt' might the right English word...) the tank 360 degrees (one full turn),
with the lid on the upside I turn it 90 degrees,
then do another 360 rotation,
all within about 6 seconds.

I'm beginning to to think that I over-filled my tank, but I'm not quite sure yet. I guess I should also improve my agitation?

What pops into my mind:

does anybody have experience with agitation every minute in small tanks? I thought maybe this could solve the problem in the LPL tank with stainless reel...?
Less agitation means that I have to extend the developing time.

Very weird. Just had this problem with a roll of Tmax 100 I developed on a steel reel yesterday. Although it showed uneven kind of mottled development all over it certainly had a pronounced over development on the edges. I struggled to get the roll on a 120 patterson reel and failed. I don't know if it was too humid in the changing bag or what. So I abandoned the Paterson reel and loaded the thing onto the steel reel. The problem with the steel tank is it takes longer to pour stuff in because it air locks if you are too aggressive. So developer and stop went in slow. The negative was a total write off. I was using pretty fresh stop and freshly mixed rapid fixer. The Xtol is a few months old but it beautifully developed a tmax 100 negative a week ago. I agitated pretty aggressively once a minute. 30 seconds initial agitation once the developer was in. Strange.

I expect that your agitation method may be at fault. There may be a language issue, but I am not sure what you mean by rotating or tilting 360 degrees - and then turning 90 degrees for another 360 rotation. I can't quite picture that. If you are inverting the tank, we should be talking 180 degrees; in other words - turn the tank upside down.

Here's the Ilford instruction: "turn the tank upside down four times during the first 10 seconds and again for 10 seconds (that is, four inversions) at the start of every further minute to agitate the developer. Each time you invert the tank tap it on the bench to dislodge any air bubbles which may have formed on the film." (From http://www.ilfordphoto.com/Webfiles/200629163442455.pdf)

Kodak: "For an invertible tank, one cycle consists of rotating the tank upside down and then back to the upright position. For a noninvertible tank, one cycle consists of sliding the tank back and forth over a 25.4 cm (10-inch) distance. With tanks that have a handle for turning the reel, rotate the reel back and forth gently through about one-half turn at a rate of one cycle per second during the agitation intervals. After the first 30 seconds, agitate for 5 seconds at 30 second intervals. Agitation should consist of 2 to 5 cycles, depending on the contrast you need and the type of tank." From http://www.kodak.com/global/en/professional/support/techPubs/j78/j78.pdf

The operative thing here is to invert the tank (if that's possible) and then give it a good bump to dislodge the bubbles. Obviously, there should be room enough in the tank for bubbles.


Note that Ilford recommends 10 seconds once a minute and Kodak, 5 seconds twice a minute. Both come pretty close. The trick here is consistency. It may (or may not) make a difference, but which interval that you prefer is subjective.

Noble said:

The problem with the steel tank is it takes longer to pour stuff in because it air locks if you are too aggressive. So developer and stop went in slow.

Click to expand...

Tilt the tank slightly (experiment) while pouring in solutions. They'll go in faster than if the tank is flat on a counter.

Seriously, folks, tens of thousands of us have successfully used both steel and plastic reels for decades. The "one is better" or "I can use one but not the other" comes up on this forum frequently. It's usually technique, not equipment.

Yes, turning it upside down is what I mean. Couldn't really define it properly. Sorry for that.

So, talking in Kodak terms: I do two cycles every 30 seconds.

By now I figured out that it's not the equipment that's faulty.
I'll see if I can make a scan of the negatives and post it here soon.

I actually found that the red plastic area in my Patterson tank was leaking when I turned the thing upside-down. So, now, I just use the plastic agitator key to swirl the reel back and forth for 10 seconds per minute. This works great for me!

If the problem is knowing how to get the liquid to swirl, just leave that variable alone and swirl the film instead.

Couple of observations from a 30+ year Patterson tank user. Always start vigorous agitation as soon as the developer is poured in. Most developers froth as you pour them in and you have to get agitation started straight away. I do about 4 inversions in a 10 second period where the tank is turned completely upside down, hold the tank upside down for a second or two to make sure all the developer drains off the film and then turn the tank back right side up. Always tap the tank sharply on the counter after agitation and make sure to "burp" the lid after the solutions are poured in. I never used the twirler as I usually lost them soon after buying a new tank and I don't believe they give enough agitation. If you have ever seen a nitrogen burst developing setup you will never be afraid to give a film too much agitation. I do all my film developing on a jobo now which is continuos agitation.

They all leak if you don't "burp" the lid!

rwreich said:

I actually found that the red plastic area in my Patterson tank was leaking when I turned the thing upside-down. So, now, I just use the plastic agitator key to swirl the reel back and forth for 10 seconds per minute. This works great for me!

If the problem is knowing how to get the liquid to swirl, just leave that variable alone and swirl the film instead.

Click to expand...

Suddenly

I realised that I hadn't really finished this thread - don't know if you have to, but I feel like I need to put down some sort of conclusion.

Anyway, I gave up on the stainless steel stuff for processing roll film. Paterson 4 just works very well for me, I only had uneven development a few times. Last week I developed more than 20 rolls of old Tech Pan and everything went well (it's quite vulnerable when it's wet). I also got a lot of Paterson stuff for free, so I guess I was meant to be using it.

In my experience developing tanks always leak (a little), but I don't care because I wear gloves when I work with chemicals.

In the original post you state that you do a pre-wash of 1 minute. Have you tried longer? I extended to 3 minutes pre-wash and found my skies were getting better at the very edge so, being simple minded, I extended the pre-wash to 5 minutes and they became "perfect". Well good enough for me anyway.

RR

I don't bother agitating at all or a prewash with

stock ID11
stock Microphen (or ID68)
Rodinal 1+25 to 1+100

Just pour in developer and set timer.

Im well lazy.

But if you intend to invert you need to use the minium liquid eg for Patterson the bottom of tank has the amount and a clip on the centre cylinder if there is free space above the spiral - the clips came with the tank.