Uneven development - too much agitation?

arunrajmohan

arunrajmohan

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I am looking for both help and clarification because I have not seen this in the past four years and I do not want this happening again. Please see this image,

http://farm3.static.flickr.com/2751/4340866193_5031eb6ac2_b.jpg

I ran two rolls of tri-x in dd-x 1:4 in a single Paterson developing tank for 5 minutes at 20ºC and as I have been doing for over a year I impose an initial 30sec of slow inversion followed by two inversion every minute. Things newly introduced for this processing include three minutes of 2.5% borax solution after dd-x without any agitation and I usually use 1:9 dd-x but here I used 1:4. Just one roll in the tank (do not know which one) showed this artifact in almost all the shots.

I was reading this website where there is a similar picture and the explanation is that it is due to over-agitation.

www.olympusmicro.com/primer/photomicrography/bwprocessingerrors.html

Is that right? I think the shorter developmental time caused this effect. (scratching the head 🙁 ).
 
over-agitation is almost certainly the culprit. The sproket holes allow more developer movment so they leave the dark (on negatives) streak. Sometimes just a water rinse before developer can alleviate the problem.
 
Use a presoak, and be sure that you have sufficient liquid in the tank. It doesn't sound like you are over-agitating unless your "slow" inversions are really forceful. Even when only doing one roll in a tank, use a tank full of liquid. Also, try undoing the things you changed one at a time to see if either of those is the culprit.
 
Excess agitation can only be a problem if it is insufficiently random, i.e. if the dev is always flowing in the same direction at the same speed. Otherwise, even constant agitation works well. Twist the tank as you invert it. UNDER-agitation is a likelier culprit in most cases.

Sorry, but I completely disagree with Chris101. Pre-soaks are at best harmless, never useful, and all you need is enough dev to cover the film. Less dev = BETTER randomness. Consider inverting a new jar of orange juice and a jar 2/3 full.

This is not just my opinion but Ilford's too.

Cheers,

R.
 
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Enough developer and then fixer in tank?

Enough developer and then fixer in tank?

Clearly its the sprocket holes influencing something. With B&W you'd have to be quite zealous to over agitate. Are you sure there was enough liquid in the tank? Certainly a prewash is a good ida but I'm sure you do that already. Also, I'm assuming the chemicals were properly mixed and at temperature.

John
 
No such thing as overagitation unless you are trying stand development.

Agitation must be vigorous and of a random nature so developer gets replenished over the whole surface of film every time other wise you get underdeveloped areas. Once an area is replenished, the process is at completion and does not need more until the next cycle.

"surge marks" are the same cause. BS.

The cleanest developent I ever made is one film in a two film tank and only enough developer to cover the film on bottom reel. Agitate by inversion.

If over agitation was a problem, machine development woud never work.

And don`t use that twisty stick for anything but the first agitation cycle. There is lots of empty space at the top of a Patterson tank to simulate the one roll/two reel tank above.
Basically they are fool proof if you invert twice per cycle and don`t be gentle or you set up patterns.

There is all kind of miss information out there and people believe what they read. Both Ilford and Kodak have detailed instructions on the net and they all recommend vigorous agitation methods. Now if you think you know more than they do?
 
Hmmm…. Lots of suggestions and some are contradicting. But I do not think, I would rely on anything else more than RFF for advise on such issues as I have right now.

like2fiddle: I do agitate quite fast for 30 sec initially. However I have always been doing that and have not seen this phenomenon.

wpb & chris101: My method is to put the film in the tank, fill it with tap water and then prepare the developer solution. So I always have an approx. 5 minutes of presoak.

chris101: I will undo the new changes one by one and see which one has this effect and I will get back.

Roger Hicks: Thank you for suggesting adding a twist to the inversion. I have always thought about that but since I have not had a issues I have not tried that. Now that with dd-x 1:4 the dev time is 5 minutes, think I should consider the twisting motion to ensure that the developer moves all over.

Penceler: I prepare exactly 600 ml and I have always been doing a presoak. I prepare the chemicals in a measuring cylinder and there is a chance the initially the chemicals are not well mixed. I will try to mix the developer in a beaker and ensure that I mix it well and repeat the same run an see what happens. I do wish to keep the process, film and chemistry the same as I think I love the tone I got albeit the streaks. Yes I do wash mu reels and tank with distilled water before I dry them out.

dfoo: I change the fixer in the bottle (600 ml) once a month and I usually fix about 8-10 rolls. I have developed 4 more rolls after that (in hc110) and I have seen no streaking.
 
Two things cause this effect:

1. overly violent agitation - This is not to say "over-agitation" in the sense of two frequent or too many cycles. It occurs with overly forceful agitation that creates excessive turbulence as the developer passes through the sprocket holes creating more agitation in those localized areas. The sprocket hole pattern occurs with inversion agitation. When overly forceful agitation occurs with tanks where the reel is spun, the effect is often an increase in developer activity down the middle of the film though most or all of its length though the sprocket hole pattern can occur when the spinning is a short back and forth spin.

2. mechanical "exposure" - All silver films will react to strong enough mechanical stress the same what as exposure to light. The stressed area will develop darker just as if it was struck by light. A pattern of lines extending down from each edge of the sprocket holes, rather than centered on the holes, often occurs when film is rewound by turning the rewind crank/knob the wrong way. This winds the film the wrong direction on the cassette's spool, bending sharply just inside the cassette. If this is the cause, you can usually see matching ripple in the plastic film base when viewed at an angle with light reflecting from its surface.
 
Roger Hicks said:
... Sorry, but I completely disagree with Chris101. ...
... This is not just my opinion but Ilford's too. ...
Click to expand...

No need to be sorry Roger! I'm cool with Ilford disagreeing too. (I love their film, but not their chemistry. Go fig.)

My advice was based on my empirical findings. Presoaks and full tanks have solved similar issues for me. But images can be deceiving. The marks shown could be the result of a light leak for all I know. One can only try doing things differently and see what happens with different changes.
 
Thanks everybody. Guess I have now lots of factors to look into and I will give them a try and see how it goes. I am still leaning towards fast pouring of the developer into the tank and just 5 minutes of development. Think the short development time was not enough to even out the some of the effects.

Dwig: I've not wound my film the wrong way in almost 5-6 years. Sometimes I do it when I get a new camera, but a Leica forces you to do it a certain way and so I get it always right.

Ronald M: Previously I've been burnt by over zealous agitation and extreme contrast. Now a days I am pretty gentle plus I like DD-X and D-76 due to their not so contrasty look.

Thanks again for the suggestions.
 
I'm not sure if you figured out your issue -- but based on what I've read about your method, I'd say you UNDER agitate. I had the same issue you show in your attached image. I thought MAYBE I was over-agitating -- but after a lot of research - and then actually trying a new method - the problem was resolved.

I was reading my darkroom cookbook a few years back - and read that if you're developing film for less than 6 mins (could have been 5 mins) - you have to agitate every 30 seconds - and furthermore you agitate for a full 10 seconds. Also -- another turn or two would help with the evenness of development. I didn't believe it - it couldn't be true! But -- I tried it -- I was having wicked ugly density build-up just as I see in your example. When I changed to agitating every 30s for 10s -- about 4 inversions -- I got the most beautiful negs -- and skies... Period.

Now -- whenever I have dev times less than 7mins -- I agitate every 30 seconds. If I know I have lots of sky and contrasty scenes, I give it another inversion or two (I usually invert 2-3 times normally in 10 seconds).

Experimenting helped me a lot -- and just trusting what I read. Even after many years of developing my own film I still learn something 🙂 Hope this helps...
 
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