Minimal Agitation the Sweet Spot or a Waste of Precious Time?

My $0.02. It depends, but I generally stick with what I know for testing new film and extrapolate based on first few sheets of the new film.

Are you using dilute developer for long periods of time to increase edge effects or merely normal dilutions and taking longer breaks between agitations to try and achieve the same thing. Are you trying to compress highlights for high contrast scenes or practicing normal development on average SBR scene.
Do the scenes lead you to try to open the shadows or are the shadows unimportant.

The main thing I have learned about agitation is to give plenty during the first two minutes. This solves the issues of uneven development in open sky and solid tones. After that you can try to manage edge effects by letting the iterations run longer and/or relying on dilution/exhaustion. I find most of the Pyrocat variations (HD, Metol, Obsidian Aqua) allow some flexibility depending on how dilute you want to go and how much time you want to spend. A very dilute solution over long period is only slightly different than a normal dilution over a shorter period using 2-3 minute agitation. Where high dilution methods shine is where you expose for great shadow detail but have to compress the highlights to bring them back under control.

I also believe you can enhance edge effects somewhat by using a bleach/redevelop method on the print as well as unsharp masking . But that again is subject to time, effort, and ones preferences.

I ended up at least with Catlabs X 80 going with normal agitation. Normal for me being 5 seconds every minute and 30 seconds to start.

Using 510 Pryo with a starting point of 10 minutes at 20C, I determined my ASA to be 32. FB+F is .03 and my Zone I density is .13, right on the money. I'm not surprised that 32 is the figure here as 80 seemed optimistic to say the least in my tests.

However when I went on to do my dev time test my Zone VIII density only achieved .97, and my zone X is 1.24.

Is the answer here to lengthen development time? Wouldn't lengthening development time also possibly increase my film speed? Or will FB+F and Zone I increase overall at the same amount, keeping my ASA speed the same?

Generally (in my experience and reading) developing to higher contrast has only a small effect on true speed; if you do (in this case) a one zone expansion, you should see only very tiny increase in your Zone I density. As you note, your fog level will increase just about in sync with your Zone I (though the base density underlying the fog won't change, so FB+F will increase more slowly). These values are so little separated, though, that it would take a lot of expansion to push your Zone I value up to Zone II -- probably more expansion than modern films can give.

I started with a Zone I density of .08 actually when I did the ISO test, which I felt was close enough to tell me it's 32. Then I increased development time to 10 minutes from 9:30 seconds which gave me a Zone I of .13. If I do some unscientific extrapolation that would mean an expansion of .05 per 30 seconds, meaning I could get a Zone VIII density in the 1.25 range at 13:30 seconds. Again I'm sure that my extrapolation has some flaws there, but I'll go ahead and try that time next.

I recollect that under actual ISO (as opposed to 'zone') test conditions, the Catlabs/ Shanghai film works out to be 50-64 speed in non speed increasing developers, so getting an EI of 32-ish under zone test conditions sounds like you're in about the right sort of range.

(snip)

Just thought I'd do an informal poll. Should I stick with the minimal agitation or quit screwing around and go back to 5 inversion every 60 seconds?[/QUOTE]

Since I now use only 4x5 and 8x10 sheet film I took to continuous rotation with the film in BTZS tubes (floating in a Tupperware tub with water 'at temperature) when a 'working Pro' I had the use of a Wing Lynch 'processor' for All my films (B&W as well as Ektachrome. I will never go back to 'hangers in tank" (or tray development) for any of my sheet film. The occasional 35mm/120 B/W is processed in Kindermann tanks (about 2/3 full and rotate the tank in the horizontal position.

Works well enough for me .

Ken

So for Catlabs X 80 I've settled on 32 ISO. I'm doing 510 Pyro at 14 minutes, 20C, 5 seconds of inversion every minute. It seems like I keep screwing up my full H+D curves but the negatives I process look great.

Two and a half years after: about this thread's title...
Reduced agitation and minimal agitation have their place.
I don't use them for grain/sharpness effects, but for tonality under direct sunlight: compensation.
About the risk of uneven development: never ever in my case. I don't know why, but I know how I do it:
I've gone up to 5 minutes without agitation with D-76, and up to 6 minutes with HC-110. Everything's been fine.
I develop 35mm film inside a 600ml tank. I develop a single roll in the bottom, without a second reel inside.
2 slow twisted complete inversions.
5 and 6 minutes are my most extreme use: only when I'm interested in uprating ISO400 film to EI800 including sun scenes.
For common sun contraction at box speed, diluted developer + 3 minutes without inversions are enough.
I use a current MF Kaiser condenser enlarger: maybe softer light enlargers don't require that level of contrast control.

NortheastPhotographic said:

Should I stick with the minimal agitation or quit screwing around and go back to 5 inversion every 60 seconds?

Click to expand...

There truly is only one way to know. Try it both ways, and decide which gives you the results that you like best.

Aren't Kodak's and Ilford's agitation schemes, 5s/10s every 30s/min, more appropriate for the recommended (overcast) times, than for direct sunlight and its much higher contrast?
I can't control contrast equally well if I agitate that much.
For soft light well exposed, and for expansion, I do.
For pushing, I agitate less too.

Friends do not let friends use stand development or minimal agitation. Follow Kodak or Ilford recommended agitation directions. They both work and neither one will kill you.

Using a single agitation scheme for everything, is like using the same development time and dilution for everything.

If you are giving sufficient agitation to not get uneven development, you aren't delivering minimal agitation - you are merely affecting overall contrast outcomes in a way which could be better effected via time adjustment & regular agitation.