Question On Developing Times & Agitation Methods

[IanBarber]

I appreciate that everyone probably has their own agitation methods and most likely use the developing times from either their own experimentation, film manufacturers tech sheets etc but I still have a question.

Iiford for example say to agitate for the first 10 seconds and then every 10 seconds of every minute.

Kodak say agitate for the first 30 seconds and then 7 inversions every 30 seconds.

Is it good practice to use the manufacturers methods or is it quite feasible to stick with one method for convenience. What I am trying to say is... will using what the manufacturers say, give me a better chance of yielding better results.

 

[Peltigera]

Consistent agitation is most important. I use four inversions every minute regardless of which developer I am using.

 

[IanBarber]

Consistent agitation is most important. I use four inversions every minute regardless of which developer I am using.

And do you use this method regardless of what film you are using ?

 

[Rick A]

Consistent agitation is most important. I use four inversions every minute regardless of which developer I am using.

Same here, no matter which film or developer in small tanks. I use rotary for sheet film, which is constant agitation, which means reduced developing times.

 

[jeffreyg]

As you say everyone has their own system. I stick with the mfg's box speed, time and temperature unless more time for more contrast is desired. I do 15 inversions the 1st thirty seconds and then 4 inversions every thirty seconds. The same for all films with inversions changed to agitations for 4x5 film. It's worked for me for 45 years.

http://www.jeffreyglasser.com/

 

[Gerald C Koch]

Development is diffusion controlled therefore increasing agitation is only effective up to a point. Changing the agitation method is really a poor way to change what should be done by changing development time or temperature.

It really has little effect whether you invert a tank 2 times every 30 seconds or 4 times every minute. It is an example of de minimus dealing with trifles.

 

[bdial]

What's important is to pick a method that suites you, then be consistent. And if you change, know why you are making the change, and have a specific goal in mind. You can fine-tune contrast with agitation, but, as Gerlald notes, changing time or temperature is more effective for that (usually time). I sometimes alter my agitation scheme if I want to make small adjustments for contrast, for example using a 1.5 minute interval instead of every minute to reduce contrast slightly, for example.

 

[MattKing]

If you choose an agitation scheme and stick with it, you are much less likely to mess up a roll due to distraction.

For me, in the developer, it is 30 seconds with continuous rotary agitation to start, and then I take the tank off of the rotary agitator and use 5 seconds of inversion agitation with twisting every 30 seconds thereafter.
For Stop bath, fixer 1, fixer 2, HCA I use continuous rotary agitation.

 

[BetterSense]

What I puzzle over more than amount of inversions is the intensity of agitation. I was taught to invert very gently, so gently that you can't hear any sloshing sounds. This was to avoid surge marks around the film edges and sprocket holes. Since then, I have been told by other people to agitate vigorously like shaking a martini. This was to avoid air bels and bromide drag. They both can't be right. How where you taught?

 

[Gerald C Koch]

Kodak recommends combining the inversion with a swirl. They often feature a diagram on the instructions for film or developers. All that is needed is to move the bulk of the developer in the tank. More vigorous agitation may lead to problems.

I really don't know if Ian Fleming was just looking for a tag line. Shaking will certainly bruise the gin as air enters the drink causing loss of some of the essential flavors of the vermouth and gin. Some have explained that stirring runs the risk of diluting the drink too much Whichever method is used the key is to get the drink away form any excess ice. In other words serve it immediately. Making a pitcher of martinis results in disgusting gin flavored water.

Violent shaking also causes air (oxygen) to oxidize the developing agents. So it doesn't do the developer any good either.

 

[Ko.Fe.]

Slow inversions, fast inversions. 30/5, 1/10 agitation. I have tried it all. But because I'm multi-tasking, it is sometimes 2 minutes, 20 seconds.
I'm using manufacturer data as reference only, because I never measure temperature of developer.
And I'm using S16 instead of TTL and incident. Guess what? I'm getting printable results with all of it. Why? Because modern bw film is very forgiving.

 

[Kyle M.]

I try not to reply to threads like this because someone is almost sure to come along and tell me I'm wrong and that I'm ruining my film. But you know what? I like the negatives I get, they scan well (yes I said the horrid s word) and I'm very happy with them. What other people think of them I could care less. That being said for sheet film I use rotary processing and so far have not had to decrease times. For any roll film regardless of manufacturer or developer I do 10 seconds of initial inversions followed by 5 inversions every 30 seconds starting at the 1 minute mark. I've been doing it this way for 3 years and have no complaints.

 

[Peltigera]

And do you use this method regardless of what film you are using ?

Yes.

 

[David Brown]

Iiford for example say to agitate for the first 10 seconds and then every 10 seconds of every minute.

Actually, Ilford has published 10 sec once a minute in one document and 5 seconds every half minute in another. Works out to the same amount of time. Consistency is the key.

 

[Gerald C Koch]

But because I'm multi-tasking,

Multi-tasking doesn't work not even for computers unless they have multiple CPU's. Us poor humans have only one. What people think is multitasking is actually called time-slicing. You work on one problem for a moment (a time slice), do a context switch and then work on another problem (another slice). Try patting your head while rubbing your stomach. The reason it is so difficult to perform this simple task is that the bran cannot concentrate on two things at the same time (single CPU). It is easily shown that attempting to "multi-task" two problems actually takes more total time than doing them sequentially. The devil in the details is the amount of time it takes to do a context switch each time you switch problems. They all add up. So save yourself some time and single task.

 

[Ko.Fe.]

...problems. They all add up.

Since then developing film and changing LP became as the problem?

 

[Gerald C Koch]

Since then developing film and changing LP became as the problem?

When I'm developing is when I take advantageoof the latest ear worm rather than depend on LP's.

 

[tedr1]

I think the reasoning behind agitation goes like this, I am not a chemist however and can't claim to be an expert.

The liquid developer in contact with the emulsion is converted by the emulsion to by-products which alter the local concentration of active developer compounds. When the liquid in contact with the film is stationary the rate of development is not constant because of this. Agitation removes the local concentration of partly exhausted developer and replaces it with fresh developer. Secondly development proceeds at different rates in the areas of shadow and highlight exposure, and proportionally in between these extremes. The result is that the chemical composition of the developer changes at different rates in the various parts of the negative in response to local exposure variations of the image. Once more, agitation removes the partly exhausted developer and replaces it with fresh developer so that the development rate for highlights and shadows is more evenly balanced than it would be without agitation. The result of using agitation is a closer approach to the ideal situation of a negative that is developed in a moving stream of fresh developer that is unaffected by the exhaustion effect that occurs with stationary liquid.

I process film in small quantities and each time I follow the instructions of the developer manufacturer very carefully with the aim of consistent results.

 

[Doc W]

I try not to reply to threads like this because someone is almost sure to come along and tell me I'm wrong and that I'm ruining my film. But you know what? I like the negatives I get, they scan well (yes I said the horrid s word) and I'm very happy with them. What other people think of them I could care less. That being said for sheet film I use rotary processing and so far have not had to decrease times. For any roll film regardless of manufacturer or developer I do 10 seconds of initial inversions followed by 5 inversions every 30 seconds starting at the 1 minute mark. I've been doing it this way for 3 years and have no complaints.

Kyle, the consensus seems to be pretty much what you are saying, i.e., find a method and be consistent.

I am a little surprised that you don't reduce the time for rotary processing. Are you saying that you use the same time for rotary processing with sheet film that you do for the same film (roll) in an inversion tank?

 

[Loren Sattler]

Kyle, the consensus seems to be pretty much what you are saying, i.e., find a method and be consistent.

I am a little surprised that you don't reduce the time for rotary processing. Are you saying that you use the same time for rotary processing with sheet film that you do for the same film (roll) in an inversion tank?

What I puzzle over more than amount of inversions is the intensity of agitation. I was taught to invert very gently, so gently that you can't hear any sloshing sounds. This was to avoid surge marks around the film edges and sprocket holes. Since then, I have been told by other people to agitate vigorously like shaking a martini. This was to avoid air bels and bromide drag. They both can't be right. How where you taught?

BetterSense, my experience with agitation may answer some questions and satisfy some curiosity. For years I agitated every 30 seconds with light agitation (not inversion) in stainless steel tanks because that was the way I was taught. Most of my shooting was 120 film. My developer was D76 1:1 and films were Tri-X and Plus-X. This lead to problems with insufficient development along the film edges where the film engaged with the spool. The problem was noticeably worse with Plus-X for some reason. After reading about the value of vigorous agitation I adopted the Kodak published method about 10 years ago (5-7 vigorous inversions every 30 seconds) and my problems of uneven development went away, although occasionally I would still have a minor edge issue with Plus-X. Never an issue any more with Tri-X. Of course Plus-X is gone so that issue is gone. If I wanted to include the edge of the negative in my print, I would need to burn in the edge which was workable but inconvenient.

So my conclusion that vigorous agitation solves or prevents uneven development is counter intuitive. My common sense suggests it should contribute to uneven development (all that developer rapidly surging where the film meets the roll or surging past the sprocket holes on 35mm film) but the reality is that vigorous agitation contributes to more even development for reasons I do not understand.

Hope this helps.

 

[Loren Sattler]

Correction on my above post. The uneven development that occurred with light agitation was actually over-development (extra film density) along the film edge (not under-development). Again, as mentioned above, the solution was burning in the edge during printing.

 

[bdial]

What I have found from reading many, many threads about developing problems, and teaching darkroom work is that agitation technique ends up to be a very personal thing. What works for me may, or may not, work for anyone else, and vice versa.
The takeaway IMO is to pick a method, any method, if you end up with negatives that satisfy you, great, do more of that, if not, introduce a change and evaluate. The change that works might be more vigorous agitation, less vigorous, more cycles or fewer cycles, any and all have worked for someone at sometime.

Once you find a technique that works, most of the time you can just continue that... at least until something else changes

 

[MattKing]

What I puzzle over more than amount of inversions is the intensity of agitation. I was taught to invert very gently, so gently that you can't hear any sloshing sounds. This was to avoid surge marks around the film edges and sprocket holes. Since then, I have been told by other people to agitate vigorously like shaking a martini. This was to avoid air bels and bromide drag. They both can't be right. How where you taught?

I'm one of those who believes in sloshing.

I expect that surge marks are a function of tank and reel geometry and film and developer combination as well. And obviously, surge marks are normally only a concern with perforated film.

One thing I am sure of though is that it is best if the direction and intensity of agitation is reasonably random. With the plastic tanks, I think you should hear a gurgling slosh as you invert and twist.

I don't count inversions, because bigger tanks will have fewer but bigger turns.

 

[Bill Burk]

I really don't know if Ian Fleming was just looking for a tag line. Shaking will certainly bruise the gin as air enters the drink causing loss of some of the essential flavors of the vermouth and gin. Some have explained that stirring runs the risk of diluting the drink too much.

My idea of a perfect Martini is that it must be stirred for the initial 45 seconds and then let it stand for 7 minutes. This allows the fresh cracked ice to bring the temperature down to just above the freezing point, adding the right amount of water and leaving "shards of broken glass" floating on top.

My theory is Ian Fleming knew that James Bond wasn't going to wait around for 7 minutes for anything.

But I'm with you... the perfect Martini is stirred, not shaken.

 

[Thomas Bertilsson]

Actually, for me agitation is a tool. If I shoot in high contrast lighting I slow down agitation to maybe every 3 minutes, which helps to (significantly) lift the shadows, while getting slight compensating action in the highlights. Doesn't work with all films and developers, but it works really well with the films and developers I use.

The difference is so big that you can easily measure it with a densitometer, and increase your film speed quite readily, which is a good thing in that medium high to high contrast light.
Anything in low to medium medium light receives a standard agitation every thirty seconds in my case, because there's going to be plenty of shadow detail, but often the highlights need a boost to print with 'authority' as I like to call it.

Anyhow, the difference between every 30s and every minute isn't going to show much difference. It isn't until you start extending out to every 3 minutes, or even every 5 minutes that things start to really happen.

The picture of Isaac is an example of where I processed the film using standard agitation.

And this picture of Erin required reduced agitation at every 3 minutes to get some more shadow detail without blowing those highlights beyond printable. If I had simply shortened the developing time, I would have ended up with far less shadow detail than I was able to rescue.