AGITATION MADE EASY AND PREDICTIBLE

[David Lyga]

Often people post problems with agitation and inquire how to obtain foolproof negatives that don't have irregularities (especially between the sprocket holes!)

There are advocates of slamming the damn tank to obliterate nasty air bubbles and there are those that advocate strict '30 sec' or '60 sec' timings between movement.

I really think that my way solves all problems forever and I have employed this method for years with absolutely no problems. How? I fill the tank only half full with developer. Then, I immediately turn the tank on its side and begin rotating it throughout the development time. This absolutely guarantees that no film area will be left behind in the consistent development process. (Consistency is a must because development is most always NOT done to completion, unlike fixing.) I find that using a water bath to rotate the tank in is best for two reasons: first, it is easier to rotate because the tank becomes lighter in water and, second, because I believe that the solution actually gains a few degrees in temperature, probably because or the reaction involved. For the rotating, I usually make one 360 degree turn every five to ten seconds. One problem, especially with the Patterson tanks, is the that top part is much thicker than the bottom of the tank. You could pad the bottom part of the cylinder with something think and pliable if you wish (sealed with duct tape?) or not worry, as the amount of developer will really cover all film as the film is exposed to the solution each rotation. And, bonus, you will use far less developer. The fear of 'using up' the capacity I feel is greatly exaggerated and developers really are formulated to allow more dilution than allowed for in standard literature. My experiences affirm all this. NOTE: I do the same for the stop and fix. - David Lyga

 

[Diapositivo]

Jobo used to produce some "table rollers" which have the purpose of making a rotating development without the rotating processor. You put the tank on the rollers and then just roll the tank. That's better than having the tank rotating on the table because tank are typically larger on the top so the tank wouldn't be perfectly horizontal during development.

 

[David Lyga]

That's why the water bath: it makes rotating easier. But your method is even easier (but more expensive for some). - David Lyga.

 

[Gerald C Koch]

Not all tanks are leak proof when placed on their side.

 

[MaximusM3]

I have used stainless steel tank/reel, with regular amount of developer, on its side for continuous agitation with XTOL 1:2 or 1:3 for expansion/contraction development and negatives have always been flawless. In fact, developed a roll of TMX 120 last night for 14min (N+1) with XTOL 1:2, continuous agitation as above, and it came out perfect.

 

[David Lyga]

Gerald Koch: well they SHOULD BE LEAK PROOF. Let's start a revolution. (NOT a pun, but a political statement.) - David Lyga

 

[Juri]

Why not just rotate the reel? No need to mess with water bath, worry about leaking, air bubbles and agitaing it too vigorously. With consistent rotating method the results will be even and consistent.

 

[Gerald C Koch]

Gerald Koch: well they SHOULD BE LEAK PROOF. Let's start a revolution. (NOT a pun, but a political statement.) - David Lyga

I agree 100%! All SS Nikor tanks which I use are notorious for leaking. I used a 1/2 wide rubber band to stop this until I got Kindermann plastic lids for them. No problems after that.

 

[Diapositivo]

Any tank which is capable of being inverted and then inverted again without leaking should, I imagine, being able to withstand rolling on its side. If it leaks, it should leak during inversion also.

The advantage I can see is ease of consistency of results. With inversion one must be "concentrated" on the job for the entire length of the process: one has to invert the tank at the right moment, and keep it inverted for a number of seconds maybe, then invert it again and start counting again a certain exact number of seconds, and do this for minutes without distractions. I am a person who gets distracted easily and takes much less than 30 seconds to build a castle in the air complete of darkroom.

If you just rotate, you can set and start your stopwatch, and rotate the tank while singing until the stopwatch rings. Much less attention and less margin for mistakes. One can talk to the phone while doing it, no need to count seconds for minutes.

 

[johnnywalker]

I've tried something similar to this (putting the Paterson Tank on an electric roller for constant agitation) with poor results. I put it down to the probability that the reels were not rotating with the tank, and/or were rotating independently of the tank at a slower rate and in a more random manner.

 

[Newt_on_Swings]

Why not just dig out the little plastic agitation rod that comes with patterson tanks and rotate that?

 

[MaximusM3]

I don't see how this is any better than inversion agitation done properly, which is not rocket science. This method only allows for continuous agitation, which precludes any type of compensation effect. It also eliminates adjacency effects, which don't occur without rest intervals of ~1 minute between agitation cycles. So while this technique might work, it does not work better than inversion agitation, and is pretty restrictive.

Michael,

You can use XTOL 1:3 for N-/N-- and continuous agitation. Either way, this method can also be used for intermittent agitation and some people prefer it to inversions. I personally could never see much difference.

 

[MaximusM3]

Why not just dig out the little plastic agitation rod that comes with patterson tanks and rotate that?

Some people say that's horrible and doesn't work. It does.

Here is an interesting link from prof H. Lynn Jones. I have followed many of his suggestions over the years and have never been disappointed.

http://www.austincc.edu/photo/pdf/bwdv_prc.pdf

 

[jordanstarr]

3 words...dip n'dunk

 

[MaximusM3]

For intermittent or reduced agitation I assume you'd just roll it during agitation and then let it stand upright? Fine, but I still don't see how this is any more consistent than inversion agitation. People who have development problems and artifacts with inversion agitation are doing something wrong plain and simple.

Regarding XTOL 1:3 (or practically any developer for that matter) for N-- with continuous agitation, the results are somewhat different than with intermittent or reduced agitation.

I'm not saying you can't roll the tank around for agitation. Perhaps it works ok, but I think it is at best misleading (to beginners who might be reading, for example) to call it "agitation made easy and predictable" as though it were some kind of fail-safe technique. I disagree with that premise.

Hi Michael,

In a perfect world, continuous agitation would be ideal for every situation/developer but no, it's not the case. You are right that it is misleading, as continuous agitation, by inversion, rolling pin, bartender style, whatever, cannot always be used, and certainly not for any compensating methods. No offense to David, but I have done plenty of stand development with great results so, to say that there is a foolproof method for agitation and perfect negatives, would negate the very existence and validity of it. I would personally rather make the claim..."put the roll in the tank, pour developer, leave for an hour, perfect negatives". That sounds better than rolling around for 20 minutes
The only way that agitation could be made easy and predictable, it's no agitation at all. Everything else is just different ways to arrive at the same destination, which is a good negative that can be easily printed.

Max

 

[wogster]

Often people post problems with agitation and inquire how to obtain foolproof negatives that don't have irregularities (especially between the sprocket holes!)

There are advocates of slamming the damn tank to obliterate nasty air bubbles and there are those that advocate strict '30 sec' or '60 sec' timings between movement.

I really think that my way solves all problems forever and I have employed this method for years with absolutely no problems. How? I fill the tank only half full with developer. Then, I immediately turn the tank on its side and begin rotating it throughout the development time. This absolutely guarantees that no film area will be left behind in the consistent development process. (Consistency is a must because development is most always NOT done to completion, unlike fixing.) I find that using a water bath to rotate the tank in is best for two reasons: first, it is easier to rotate because the tank becomes lighter in water and, second, because I believe that the solution actually gains a few degrees in temperature, probably because or the reaction involved. For the rotating, I usually make one 360 degree turn every five to ten seconds. One problem, especially with the Patterson tanks, is the that top part is much thicker than the bottom of the tank. You could pad the bottom part of the cylinder with something think and pliable if you wish (sealed with duct tape?) or not worry, as the amount of developer will really cover all film as the film is exposed to the solution each rotation. And, bonus, you will use far less developer. The fear of 'using up' the capacity I feel is greatly exaggerated and developers really are formulated to allow more dilution than allowed for in standard literature. My experiences affirm all this. NOTE: I do the same for the stop and fix. - David Lyga

I hate to burst your bubble, but, put 10 darkroom worker in a room together, and you will get 12 different opinions as the best way to agitate film. The real key is to make sure your method is consistent, and that it works for that particular developer and film. No one method works for every developer/film combination. Your method may work fine with some developers, but not others.

 

[c6h6o3]

I really think that my way solves all problems forever and I have employed this method for years with absolutely no problems. How? I fill the tank only half full with developer. Then, I immediately turn the tank on its side and begin rotating it throughout the development time.

If I did this with the developer I use my negatives would be unprintable. They need time in the developer when they're still. For sheet film in trays I agitate gently for 10 seconds every 30 seconds. For roll film in tanks I agitate for the first minute, and then for 10 seconds at 8 minutes and 10 seconds at 16 minutes. I stop and fix at 24 minutes. This semi-stand method produces produces perfectly consistent negatives. I've never had any trouble with uneven development.

 

[trexx]

This method is not a panacea. If it is easy to roll your tank, well be it then roll. If shaking, stirring or standing works for you fine. But I hold to two tenants.
1) Test.
2) Consistency.

I test a film with some time-temperature and processing technique. When I use that film I rely on the testing I have done to know how to process. to get predicable results. Some times it is stand. some times it is roller, some times it is 5sec every 30 some time 10 every 60. some times it is even X seconds ever Y seconds. But it is in a test. So I can get the results I am expecting.

TR

 

[piu58]

If you roll the tank instead of inverting it you get acummulation of bromide rich developer in the inner part of the roll, This leads to lesser development there. I recommend continuous inverting. Please keep in mind that you have to shorten the development times in comparision to 30 second iversions.

 

[Newt_on_Swings]

Some people say that's horrible and doesn't work. It does.

Here is an interesting link from prof H. Lynn Jones. I have followed many of his suggestions over the years and have never been disappointed.

http://www.austincc.edu/photo/pdf/bwdv_prc.pdf

Thats a nice and well written informative pamphlet, its covers a wide range of topics.

 

[Diapositivo]

If you roll the tank instead of inverting it you get acummulation of bromide rich developer in the inner part of the roll, This leads to lesser development there. I recommend continuous inverting. Please keep in mind that you have to shorten the development times in comparision to 30 second iversions.

That's interesting. Could you elaborate on that? If I get it right, you mean that the developer tends to separate inside the tank, the heavier part tend to sit to the bottom, and some silver residues tend to accumulate on the lighter part?

I have never seen problems so far with Jobo (horizontal rotation, rotation inversion) maybe because the time is rather short (7:30) or maybe because the rotation speed (70 rpm) and the inversions create a good swirl that shakes the fluids inside.

 

[David Lyga]

Folks, the real beauty of my method is that, CONTINUOUSLY, you are flowing fresh developer over the film. This film is not simply 'moved around' IN the solution. It comes OUT OF the solution and is immediately immersed back into the solution. THAT IS WHY I SAY 'HALF FULL', NOT MORE. - David Lyga

 

[Diapositivo]

Why not just dig out the little plastic agitation rod that comes with patterson tanks and rotate that?

The main reason would be that if you use horizontal treatment you can use half the volume of chemicals. That makes one-shot use cheap.

With a Jobo and a 1520 tank, using horizontal processing, you only need 240 ml for 2 135/36 rolls. These means that a 5 litres kit makes more than 40 rolls if used strictly one-shot, and more than 80 rolls if each bath is used only twice (with a rinse between bleach and fixer during the first use). That means a cost of less than €1 per roll for E-6 treatment. Further economies would be reachable reusing those baths which have greater capacity (I still have to study this aspect).

One-shot use is very nice because it allows to keep the chemicals in concentrated form and allows to always use fresh chemicals, with perfect consistency in results and no guessing-game as to the state of the chemicals.

 

[piu58]

That's interesting. Could you elaborate on that? If I get it right, you mean that the developer tends to separate inside the tank..

I gan give you a site in German which contains the result of comparing different agitation techniques:
Dead Link Removed
The most important paragraph is

"Mit zunehmender Bewegungsintensität verkürzt sich logischerweise die Entwicklungszeit. Überraschend allerdings, daß die schnellste Bewegung, die Rotation, aus der Reihe rollt: Klar langsamer als beim 3-Sekunden-Kipprhythmus, sind die Zeiten denen des 30-Sekunden-Kippens vergleichbar. Offensichtlich sorgt das verhältnismäßig unkontrollierte Kippen für eine bessere Durchmischung des Entwicklers, als die doch sehr konstante Rotation, wo wegen mangelnder Turbulenzen verbrauchter und frischer Entwickler aneinander vorbeiströmen können. Erwartungsgemäß streuen die Verlängerungsfaktoren beim dünnen Rodinal weiter, als beim üppig dosierten Ultrafin Plus. Wo wenig ist, herrscht eben auch schneller Mangel."

A try a rough translation

With increasing the agitation whe have a shorter developing times. It is surprising that the fastest agitation, the rotation, departs. Is is slower than a 3-second-inverting and comparable with 30-seconds-inverting [in reference to the developing time needed to give an equal density, piu]. The inverting leads to an better mixing of the developer. Rotation lets the fresh and exhausted developer flow laminar around instead of mixing it. The time differences are bigger in diluted Rodinal in comparision to Ultrafin Plus. Where we have little developer from the beginning the shortage starts faster.

 

[Klainmeister]

Interesting, that site makes it sound like different developers react radically different to agitation style. (my German is out of practice, but I think I got it right).