Ramping agitation time & frequency (just a crazy idea)

[radiant]

I got just an idea, so this is just a thought to share.

What if we change the agitation time & frequency during the development; starting with quite frequent and long agitation and ending the development to almost like a stand development so in the end the film wouldn't be agitated almost at all.

I myself have an automatic agitation device (do-it-yourself) so I could program it to ramp down the time & frequency. Of course the development time would be then something different than what manufactures etc. suggest.

Stupid idea or something to study?

 

[pentaxuser]

Give it a try and tell us if it makes a difference. There might be someone here who has done the same but not necessarily with the same rhythm or timing and if we haven't done the same then by definition what we say will be theoretical

pentaxuser

 

[Billy Axeman]

I wonder what the purpose is of changing the agitation scheme along development. It adds complexity and it is less reproducible.

 

[Kino]

I got just an idea, so this is just a thought to share.

What if we change the agitation time & frequency during the development; starting with quite frequent and long agitation and ending the development to almost like a stand development so in the end the film wouldn't be agitated almost at all.

I myself have an automatic agitation device (do-it-yourself) so I could program it to ramp down the time & frequency. Of course the development time would be then something different than what manufactures etc. suggest.

Stupid idea or something to study?

If you are stand developing, it suggests that you are trying to compensate for a high contrast scene by starving out the highlights and allowing the shadows to come up. Maybe if you are getting a negative that is far too flat, you could experiment with ramping up agitation towards the end of the development cycle, but then again, you can simply just agitate a bit more to get the same effect.

As with most theory, you have to give whatever a try and see what happens.

 

[Bill Burk]

I agitate each 30 seconds, but for extended development times like after 15 minutes or so, I change to every minute.

I also rap very firmly the first few agitations, then rap more gently the rest of the time.

So it does make sense to alter the pattern during a long run.

 

[Deleted member 88956]

The question is what is wrong with your development or negatives to screw with formula?

Read "Controls in Black & White Photography" by Richard J. Henry. I don't think there has been another study of this kind, ever published. When I finished reading it Albert Einstein called me for help with his research.

 

[Vaughn]

If your printing skills are top-notch and you have trained your eyes to see subtle changes in negative qualities, then give it a study and see if your interpretation of the light is improved by changing your aggitation regime.

 

[Doremus Scudder]

I have an agitation scheme for tray-developing sheet film in PMK that does something similar to what the OP describes. Since PMK is prone to streaking and uneven development if one is not careful and agitates too little, especially in the beginning of the development, I agitate at fairly short intervals for the first half of development, shuffling through the stack once every 30 seconds.

However, PMK's famous edge-effects are enhanced by using longer agitation intervals, which allows the developer in the most-dense areas to exhaust and produce by-products which bleed slightly into adjacent lower-density areas, inhibiting development there and creating Mackie lines, which give the impression of greater sharpness and a kind of "drawn" rendering of edges.

So, I decrease my agitation intervals for the second half of development to once through the stack every 60 seconds, allowing each sheet to rest for 45-50 seconds between agitations. This does the job for me superbly: I get even development and Mackie lines that I can see through the grain magnifier. Before I started reducing agitation for the second half of development, the Mackie lines were not nearly so pronounced.

Best,

Doremus

 

[radiant]

So there are some benefits in this idea! It is always so nice to hear deep thoughts and methods on this forum which wouldn't otherwise maybe discussed, like Doremus and Bill have described.

 

[removed account4]

when i stand develop in caffenol, sometimes i don't agitate until the very end of the 30 mins. at about IDK 28 mins sometimes i'd
agitate continuously thinking it was adding something extra, but i wasn't able to notice any difference.

 

[markbau]

Along similar lines, Bergger recommends using a plain water stop bath which "allows the film to continue developing in the shadows during the stop stage" They don't mention letting the tank stand so I don't really see how this could work unless you let it stand, they also do not give a time for this procedure.

 

[Saganich]

Perhaps normal agitation in the beginning of a process to minimize streaking or reach a particular CI and then reducing agitation for prolonged stand process may have advantages. Having a programmed process would be great and interesting to test our ideas about agitation. I think the effects of agitation are somewhat variable depending on the chemistry and may not be as well understood as we might think.

 

[Lachlan Young]

Read "Controls in Black & White Photography" by Richard J. Henry. I don't think there has been another study of this kind, ever published.

And the only person outside of manufacturing R&D to have actually assembled a microdensitometry setup as far as I know - which essentially means that almost all claims the amateur developer taster fraternity make about sharpness/ acutance etc can be safely ignored because they don't have the technical ability or wherewithal to differentiate edge sharpness behaviour from the effects of an increase in overall granularity etc in a properly rigourous way. It's not perfect but it's drastically better than most of the end-user aimed (as opposed to manufacturing/ imaging science aimed) technical literature.

 

[pentaxuser]

Lachlan your post makes me wonder what noticeable difference there is between a manufacturer's agitation regime and one in which the regime changes gradually as the correct development time comes to an end. If for instance you use the Kodak regime for Xtol for say 12 minute development time then this might involve say 10-15 inversions at the start then possible 3 inversions( Kodak mentions 5 secs worth of inversions every 30 secs which I have found to be 3) so a total of about 22x3 plus say 15 inversions at the start = 80 inversions. If you slow the rate down from say half way to 1 inversion every 30 secs then you get 15 at start and 30 to the half way point so 45 then 1 per 30 secs so 12 inversions so 15 + 30 + 12 = 57. Would a difference of 23 inversions (80 v 57 ) make enough of a difference to be seen in a print from a negative.

Naturally I am assuming two negs of the same scene in the same light conditions and with the user having established the correct EI for his same camera In other words all other things being equal.

Yes a radical departure from the maker's agitation regime might alter the look of the negative but would it make it any better than following the same agitation regime throughout and if it does then unless this better neg could not be achieved by any other means it would seem to be a zero sum game?

pentaxuser

 

[Deleted member 88956]

Lachlan your post makes me wonder what noticeable difference there is between a manufacturer's agitation regime and one in which the regime changes gradually as the correct development time comes to an end. If for instance you use the Kodak regime for Xtol for say 12 minute development time then this might involve say 10-15 inversions at the start then possible 3 inversions( Kodak mentions 5 secs worth of inversions every 30 secs which I have found to be 3) so a total of about 22x3 plus say 15 inversions at the start = 80 inversions. If you slow the rate down from say half way to 1 inversion every 30 secs then you get 15 at start and 30 to the half way point so 45 then 1 per 30 secs so 12 inversions so 15 + 30 + 12 = 57. Would a difference of 23 inversions (80 v 57 ) make enough of a difference to be seen in a print from a negative.

Naturally I am assuming two negs of the same scene in the same light conditions and with the user having established the correct EI for his same camera In other words all other things being equal.

Yes a radical departure from the maker's agitation regime might alter the look of the negative but would it make it any better than following the same agitation regime throughout and if it does then unless this better neg could not be achieved by any other means it would seem to be a zero sum game?

pentaxuser

Well, my main point of bringing that book up, was that Henry made an entire book about testing in a very scientific way (him being amateur photographer, but scientist by trade trying to figure how this stuff worked behind the scenes). What he proved to me and many others is that ... forget it.

There is not much majority can do to fool the physics and chemistry in a way we actually benefit from and that is because we do not have access to testing environment to see what everything does to the final result. Eye balling your print, or even examining negative with loupe on light box ain't it. Unless you use a microscope, tight tolerance temperature, ph and other measurements, AND are 100% positive entire routine is repeatable in normal working conditions. Who has that or does that in real life? I'd trust film maker in what they tell me far more than any other source. As film technlogoy changes and gets adjusted at manufacturing level, they know it, test it and come up with an update.

There are so many agitation techniques out there, all work well so long as they remain consistent and their effect is adjusted for in total times, as per tried and tested sources using them taking into account any peculiarities of own set up/gear, there is probably a lot more inconsistencies in remaining parts of our routines that are inadvertently altered each and every time we do processing, they essentially nullify any supposed findings we thought we had during testing, and hardly scientific testing.

Mr. Henry's book is still one to read I think for B&W processing, at least as much as one can digest it or stomach it.

 

[radiant]

Well, my main point of bringing that book up, was that Henry made an entire book about testing in a very scientific way (him being amateur photographer, but scientist by trade trying to figure how this stuff worked behind the scenes). What he proved to me and many others is that ... forget it.

Could you summarize the main points Henry made? It's difficult to get a book for everyone just to understand what we are discussing here.

 

[Deleted member 88956]

Could you summarize the main points Henry made? It's difficult to get a book for everyone just to understand what we are discussing here.

It was too long ago when I actually read it to make this kind of entry here, and my best summary is in my above post, that is what I took from it in the end. It is a rather thick book and all about testing, testing and more testing. Trying to fit its content into this discussion would be spending my days monitoring the discussion and referencing back to it.

I used to think science will make a better photograph, that was a long time ago. I am convinced science, if anything, will just kill the fun of making one without any impact on anything that photograph was meant to convey.

To spin it in a modern way: pixels, pixels, more pixels, bigger, bigger, and even bigger sensors, resolution, more resolution, even more resolution ... crap ... that photo still ain't no good.

 

[Europan]

My opinion is that everything not constantly agitated is underagitated. You can hardly overagitate, the only thing to happen is that the film slips out the spiral groove or gets damaged in the tray. I work with rubber gloves on, film in a holding device—spiral reel or frame—in open tubs, in the dark. I have about 20 percent shorter bath times than indicated by the film manufacturers.

 

[Deleted member 88956]

My opinion is that everything not constantly agitated is underagitated. You can hardly overagitate, the only thing to happen is that the film slips out the spiral groove or gets damaged in the tray. I work with rubber gloves on, film in a holding device—spiral reel or frame—in open tubs, in the dark. I have about 20 percent shorter bath times than indicated by the film manufacturers.

I don't think this holds water. There have been many with single agitation at start with nothing to follow producing great consistent results. And for sure you CAN over-agitate and I say this, because especially in manual agitation, there is no way to provide required consistency one time to the next.

Best is to simplify agitation routine and then stick to it. Simple is always easier to follow and repeat, and repeat is the key to knowing it was not agitation that made the difference.

I repeat my question to OP: what is wrong with your negatives? Making processing changes for no apparent reason is nothing but, as Pink Floyd had it, a ... Momentary Laps of Reason and little else (and we could now argue whether Pink Floyd put their best effort into that one, for some they seemed a bit ... agitated ... in the studio).

No single agitation technique is best course for every film/developer combination, and agitation does affect result, yet I do think it is overreaching to mess with agitation in the first place in general. At the same time, there is no way to getting the answer without simply trying it in your own set up, as there is no way to take someone else's advice at face value and expect same results. That will happen only by chance.

 

[radiant]

I repeat my question to OP: what is wrong with your negatives? Making processing changes for no apparent reason is nothing but, as Pink Floyd had it, a ... Momentary Laps of Reason and little else (and we could now argue whether Pink Floyd put their best effort into that one, for some they seemed a bit ... agitated ... in the studio).

Absolutely nothing! Should there be something wrong first?

I don't think this holds water. There have been many with single agitation at start with nothing to follow producing great consistent results.

.. and many bad experiences when not agitating enough. Single agitation technique is (as far I've understood) playing with fire. If someone succeeds on that, it doesn't mean everyone will.

 

[Deleted member 88956]

Absolutely nothing! Should there be something wrong first?



.. and many bad experiences when not agitating enough. Single agitation technique is (as far I've understood) playing with fire. If someone succeeds on that, it doesn't mean everyone will.

You're trying to change agitation, why?

Don't fix if it is not broken was the point. If you're after technicalities of your photographs, then by all means continue to experiment. My point being, it takes your photography absolutely nowhere, but worse it takes your focus away from, well ... creating an image.

My bit about single agitation technique (which basically just ensures chemicals get in contact with entire surface to be processed), which typically applies to long timed high dilution developers, works because the process is stretched for so long, other factors come into play far more than lack of agitation. I would not suggest trying it with standard relatively fast developments. And I brought this up only to highlight variety of agitations used, vastly different from supposed benefits of what is being discussed here, but in the end the core point being ... consistency and repeatability of the process coming to the forefront of any processing routines.

Do all the testing you like, but do make sure that what you see in results is:

1. direct effect of the one single change you made
2. you can do it time and again with same accuracy, then you use same batch of film, developer, and a bunch of other same things acting during your testing.

For me, squarely because of point 2, there is a point when testing becomes not just moot, but makes things worse. We entangle ourselves with these technicalities, then look at some great photographs from late 19th century and realize, man oh why! have I wasted all my time trying to alter the inconsequential steps.

BTW, I have altered my signature today with a saying from Elliott Erwitt and I think it covers my entry into this discussion quite well.

 

[wiltw]

I agitate each 30 seconds, but for extended development times like after 15 minutes or so, I change to every minute.

I also rap very firmly the first few agitations, then rap more gently the rest of the time.

So it does make sense to alter the pattern during a long run.

...and then, to contrast the above methodology, there is use of a processor like a Jobo which uses CONTINUOUS agitation uniformly from pour-in to drain-out.
Which goes to show, you can do any approach you want, as long as you to it the same each time, so that you have uniformity of process times and uniformity of results
Plainly put, if the liquid hits all parts of the film/paper in a fairly uniform manner, and the samee liquid is not allowed to sit on the same spot until it is exhausted, we get results. If you switch developer, what used to work well with one could very well NOT work well with a different developer, too.
And while our techniques might not all be the same, if they all result in a neg which can be printed with good result, it really does not matter.

 

[Doremus Scudder]

My opinion is that everything not constantly agitated is underagitated. You can hardly overagitate, the only thing to happen is that the film slips out the spiral groove or gets damaged in the tray. I work with rubber gloves on, film in a holding device—spiral reel or frame—in open tubs, in the dark. I have about 20 percent shorter bath times than indicated by the film manufacturers.

Compensation and edge effects depend on "underagitation" if you will. Unless there is time for the developer to exhaust nearly completely in the high-density areas while the lower-density areas are still being actively developed, you will get no compensation. Edge effects are similar; unless the developer in the high-density areas exhausts and creates development-restraining by-products (bromides) that can subtly affect adjacent areas, you get no Mackie lines.

If you're not interested in either of those effects, then any agitation scheme that replaces the developer that is working in the emulsion with fresh developer and clears away the developer by-products will do a great job. Constant agitation is just great as long as one doesn't agitate so vigorously as to get surge marks or areas of more turbulence that will result in uneven development (hence the usual advice to agitate rather gently). Intermittent agitation at regular intervals will give similar results to constant agitation as long as the intervals are short enough to prevent significant exhaustion of the developer and build-up of by-products in the high-density areas. Yes, the developer does slow in activity between agitations, but as long as the agitation happens before the developer exhausts in one area but keeps working in the other, the result is, for all practical purposes, the same as constant agitation. The only significant difference between constant and intermittent agitation in this scenario is the development time needed to reach a given C.I. Constant agitation times will be shorter.

Underagitating has risks: bromide drag, uneven development, etc. Those of us that develop for compensating and edge effects deal with the risks by coming up with an agitation regime that minimizes/prevents the potential defects.

Best,

Doremus

 

[Arvee]

[QUOTE="Witold, post: 2245970, member: 88956"

I used to think science will make a better photograph, that was a long time ago. I am convinced science, if anything, will just kill the fun of making one without any impact on anything that photograph was meant to convey.

To spin it in a modern way: pixels, pixels, more pixels, bigger, bigger, and even bigger sensors, resolution, more resolution, even more resolution ... crap ... that photo still ain't no good.[/QUOTE]

Nailed it!!

 

[Europan]

It is my belief that evenness and repeatability lie precisely in constant agitation, of course not boldly but for turbulation and flow all around. By that I also keep the bath stirred up at best. Edge exhaustion effects are not what I seek, I’m a cinematographer. I have portions of up to 500 feet long in large spirals.