Rotary Processing: Does processing 15% less than your tested developing time......

[Vetus]

Does the advice develop 15% less than your usual inversion tank developing time hold true when rotary processing black & white film?

 

[MattKing]

Thread title adjusted for clarity and focus.
In answer to the question: it depends!

 

[Rick A]

As MattKing stated. 15% is a starting point, you need to do some testing to get the results that please you.

 

[xkaes]

Whenever you make a change in your developing process it's essential to test it. Don't just take someone's advise. Produce some test results from the "old way", and then make test results the "new way" -- making adjustments -- until you get them to be the same.

 

[Tim Stapp]

Depending upon what type of rotary processing...

Jobo recommended a 5 minute water pre wash prior to developer to use standard inversion times, except for XTOL, for which Kodak published times for rotary processing in addition to inversion.

For films in XTOL that Kodak did not test, I've found JOBO's suggested 5 minute prewash matched my inversion developed films.

 

[Sirius Glass]

I have not found that to be the case. Often it is too much. Ilford HP5+ and FP4+ require one minute added to the 20°C [68°F] time for the negative to be thick enough to use.

 

[Sirius Glass]

Depending upon what type of rotary processing...

Jobo recommended a 5 minute water pre wash prior to developer to use standard inversion times, except for XTOL, for which Kodak published times for rotary processing in addition to inversion.

For films in XTOL that Kodak did not test, I've found JOBO's suggested 5 minute prewash matched my inversion developed films.

Ditto

 

[btaylor]

When using my Unicolor Film Drum I would run a 1 minute pre-wash and then use a 15% reduction from inversion agitation time. Worked fine, I did not feel the need for any further testing.
I don't recall the developer, it was likely a generic equivalent to D76.

 

[Vetus]

Are there any film developers that are less efficient when used in a rotary processor? I'm guessing that using stock developer
Undiluted or 1+1 works better than highly diluted chemistry, am I correct? If it depends on developer choice, which developer do you favour for rotary and why?

 

[Sirius Glass]

Are there any film developers that are less efficient when used in a rotary processor? I'm guessing that using stock developer
Undiluted or 1+1 works better than highly diluted chemistry, am I correct? If it depends on developer choice, which developer do you favour for rotary and why?

XTOL and replenished XTOL with most of the developing done with the latter. It provides better shadow detail, finer grain and better sharpness than the other developers. Plus the tonality is better and I have found that the developer is the most forgiving developer that I have every used. [Translation: one can f**kup and the film is still printable.]

 

[mshchem]

I use Kodak's rotary times with XTOL, I use Agfa's old datasheet for Rodinal I don't reduce times.

 

[Steven Lee]

Are there any film developers that are less efficient when used in a rotary processor? I'm guessing that using stock developer
Undiluted or 1+1 works better than highly diluted chemistry, am I correct? If it depends on developer choice, which developer do you favour for rotary and why?

I am not sure about the "efficient", but the spec to watch here is developer capacity. Rotary processing usually requires far smaller volume of chemistry per roll, so if you're diluting too much you risk developer exhaustion.

Another variable is developer activity. For example, the manufacturer of Ilfosol 3 insists on 1+4 dilution, but it's just too damn active in that form, so I wouldn't consider it for rotary processing.

My thinking on the subject goes like this:

• If possible, avoid rotary for B&W because it doesn't offer the same compensation effect as intermittent agitation, and excessively aerates the developer making reuse/replenishing more difficult.
• If forced to use the machine, I prefer developers with flexible dilutions and use higher ratios. My favorites are Xtol or Ilfotec HC. I suppose HC-110 also belongs here.

 

[xkaes]

In short, whatever you decide to do, test it.

I use rotary processing for 4x5 -- B&W and color -- and inversion tanks for roll film, and I ran tests for both. That's essential.

 

[Tim Stapp]

I use rotary processing for everything on my JOBO CPE+. 35mm, 6x7 and 4x5. I use XTOL straight with Arista EDU 200 primarily.

With a 5 minute presoak, 6 minutes develop and stop/fix/wash (three times, five minutes each) times my negatives turn out great (for me and my methods).

 

[cowanw]

I am not sure about the "efficient", but the spec to watch here is developer capacity. Rotary processing usually requires far smaller volume of chemistry per roll, so if you're diluting too much you risk developer exhaustion.

Another variable is developer activity. For example, the manufacturer of Ilfosol 3 insists on 1+4 dilution, but it's just too damn active in that form, so I wouldn't consider it for rotary processing.

My thinking on the subject goes like this:

• If possible, avoid rotary for B&W because it doesn't offer the same compensation effect as intermittent agitation, and excessively aerates the developer making reuse/replenishing more difficult.
• If forced to use the machine, I prefer developers with flexible dilutions and use higher ratios. My favorites are Xtol or Ilfotec HC. I suppose HC-110 also belongs here.

https://www.ilfordphoto.com/wp/wp-content/uploads/2019/08/ILFOSOL-3-June2019.pdf

I think you will find that Ilfosol 3 is used either 1:9 or 1:14; fixer is commonly 1:4.

"ILFOSOL 3 is supplied as a liquid concentrate normally diluted 1+9 for one-shot use. Dilute it immediately before use and discard directly after development. For greater economy it can be used with many films at a higher dilution of 1+14 with only a small trade off in image quality."

Also regarding Ilfosol and rotary development.

"Without using a pre-rinse, the given development times will need to be reduced by around 15% to compensate for the continuous agitation."

 

[RalphLambrecht]

Does the advice develop 15% less than your usual inversion tank developing time hold true when rotary processing black & white film?

notin my experience.I just use the straight unmodified time.

 

[Steven Lee]

@cowanw thank you for the correction!

 

[Sirius Glass]

Does the advice develop 15% less than your usual inversion tank developing time hold true when rotary processing black & white film?

not in my experience.I just use the straight unmodified time.

I have the same experience. None of the times needed shortening, but two Ilford films needed more time.