Continuous Agitation (Rolling) and Developers: Update?

I would like to address the following question specifically to USERS of CONTINUOUS AGITATION as I am just beginning down this path with my Jobo Multitank 2500 and Uniroller Base:

While there are a fair number of prior posts here on Continuous Agitation (Jobo tank + Uniroller base - or similar) and the impact of this style of agitation on development, much of it seems to be old. I am wondering BASED on EXPERIENCE, whether you find particular developers working "better" than others? Quite a few suggest high accutance developers won't work - specifically developers like Beutler or Two-Bath. My current favorite developer is Ilford Perceptol with Kodak's XTOL running second - but second only because I haven't used it as much. Are there any particular developers you would recommend or avoid based on your experience? Favorite films are Kodak TMAX-400, Ilford FP4 and HP5. Thanks!

I follow Ilford's and Kodak's recommendations for Jobo processing times with replenished XTOL and the only adjustment that I have ever had to make was to increase the Ilford HP5+ time by one minute at 68 degrees F.

JWMster said:

Jobo Multitank 2500 and Uniroller

Click to expand...

Exactly my setup for 35mm/120.

Starting this month I'm focusing on pyrocat-HD instead of using sporadically like I have in the past. With a 5 minute pre-soak and Tri-X or HP5+ in 35mm, 120, and 4x5 I've never had any drag, fog, or side effects like growing tentacles or frothing at the gills. I usually follow the documented times, but I make sure that it's a full measure on the clock and not cut short on development ever. Pyrocat negatives are harder to judge visually, they always look weak even though they have the detail where needed.

I did try two rolls of the recent Bergger pancro 400 and I'm still unsure of the combination because pancro is a relatively flat negative to begin with. 75deg @ 1:1:100 and 15min.
I will try the 4x5 variety later and boost the development time from 15 minutes to 18.

For grins I picked up some Carestream EB/RA 8x10 and ran a "how close is my guess" sheet this weekend: ISO 100 at 75deg @ pyrocat-HD 1:1: 100 and 6:00min is not too far off my measured gray. Contrast was a bit high, I may try icing my soup down to 70 for my next guesstimate.

In any case, pyrocat worked as advertised in continuous across several formats.

I am a continuous developer, all kinds of film in spiral reels up to 400 feet length since 1999. Processed my first film forty years ago. From my experience and understanding it is just the other way round, development with intermittent agitation is incomplete, underdevelopment or development not grasped at its essence.

There must be a constant flow at the film’s surface, not with great speed but so that fresh compounds always reach the surface and reaction products being dissolved from the layers are moved away. Also the baths need to be stirred up, the denser and the more diluted portions mixed, colder and warmer portions mixed. You can only achieve constant results with continuous agitation, that is my conviction. Yet, we cannot compare drum rotation with what I do with a spiral in a sumptuous bath. I use 10 liters (2.64 US liq. gal.) for 100-ft. spirals and reuse baths.

I have found that irregular continuous agitation allows me to shorten bath times by a very constant factor. This holds true for a wide range of temperatures, I measured between 19,5 and 29,5 degrees Celsius.

This is helpful. I'm pretty satisfied with the results of Perceptol (1:1), and though not thrilled with the "ISO speed penalty", the more knowledge I glean from the experts, the more the speed penalty may simply be a myth. By myth, I mean that for the tonality desired, burning an F stop may simply be locked into the process required with a given developer and film combination. Fine with me. And as you say, I find the results achieved really for the first time look like I want them to look.

But two questions come to mind:

1) I'm using Perceptol 1:1. I know some folks following a similar rotation are using stock - but often with replenished stock.... which some experts suggest performs similar to 1:1 dilution. I'm wondering whether with the small amount of developers we use in these tanks, whether the choice of more concentrated developer formulations (stock, 1:1) vs. more dilute (1:2, 1:3, and higher) is the norm?

2) In your experience, have you come across any particular developers that have NOT worked well for this approach? The rumor is that high accutance developers don't, but then Sandy King's pyrocat-HD does. So rumors of the sort that XYZ developer won't work may be untested. I simply wonder whether there is a more concrete record.

I've used three different continuous rotary processors in my past.

1. The first was a King Concept Imagemaker, not a bad machine but the rotation speed was pretty fast and some developers showed what might have been surge marks, you would see it with 35mm around the sprocket holes and along the edges on 120, working for a studio, we shot a lot of 120. The best of the lot for a film developer available at the time, middle 1970's in the machine, was HC-110, and I tried almost every other Kodak and Ilford developer. But I eventually just started using a stainless steel tank and hand processing our black and white using the marvelous Hewes reels that we got for the machine after chucking the Paterson reels. (Film tended to unroll off the Paterson reels, but my boss choose that route since he could load a stainless steel reel. King Concept was distributed by Omega and Omega sold Hewes reels for the machine and continued to sell Hewes for many year.)
2. My second exposure to a commercial rotary machine was a Photothern SSK-8 Super Sidekick. Again the option to use Paterson, this time the alternate was Jobo reels. The only black and white developer Phototherm recommended was the Tmax Developer (not RS) but they recommended using Tmax RS as I recall for developing 4x5 sheet film in their execrable sheet film cage. The Sidekick used a much slower rotational speed so I suspect almost any developer would work.
3. I have, and use, a Unicolor Film Drum on a Uniroller at home and have used it successfully with many developers over the years. I had very good luck with ACU-1, HC-110, Tmax, and maybe tried a couple of others but I lucked into a huge stack of Acu-! at $1.00 per can at a camera store sidewalk sale, almost a full case. So I used it for many years.

I love the economy of rotary processing.