Rotary agitation instead of inversion

Eric De Santiago · May 11, 2019

The instructions for my Cinestill C-41 kit say to use 4 inversion cycles every 30 seconds. I would rather do rotary agitation because the cap leaks when it’s upside down. What would the rotary equivalent of 4 inversions be?

pentaxuser · May 11, 2019

Eric De Santiago said:
The instructions for my Cinestill C-41 kit say to use 4 inversion cycles every 30 seconds. I would rather do rotary agitation because the cap leaks when it’s upside down. What would the rotary equivalent of 4 inversions be?

I don't think there is one as such. In C41 the dev time is 195 secs so that's about 24-25 inversions in total whereas a Jobo Processor must rotate a lot more in 195 secs. If you are using a rotary processor then just go with pre-set speed.If you are hand rolling then I'd just roll say 3 revolutions forward and 3 back to replicate a Jobo Processor machine, thus giving continuous rotation as per the Jobo.

Jobo tanks are virtually leak proof when inverting and Durst tanks are completely leak proof in my experience. If you have a Paterson then its reputation is not as good. If leaks are your problem and are the reason for considering rotary agitation, then it might be easier to use the 4 inversions per 30 secs for the allotted time with water and no film and measure how much liquid is lost then add that amount to the "correct" amount specified by the tank's maker

pentaxuser

mshchem · May 11, 2019

Eric De Santiago said:
The instructions for my Cinestill C-41 kit say to use 4 inversion cycles every 30 seconds. I would rather do rotary agitation because the cap leaks when it’s upside down. What would the rotary equivalent of 4 inversions be?

So you are talking using the swizzle stick? You can swizzle the stick for 5 seconds every 30, or you can look at Kodak's instructions for the old tanks that you slid back and forth in a short arc on a table top. These both work fine. Until you get to full back and forth rotary agitation like a Jobo machine agitation usually doesn't show up much difference. With C41 if you are using short times 3'15" you want to agitate at least every 30 seconds. Just stay consistent with time and temp.

AgX · May 11, 2019

"Rotary Agitation"

Typical meaning today: rotation of the whole tank in horizontal orientation (either on a table or in a respective processor)

Rotating just the reel in an upright tank seems obsolete today and I am not sure of the right term for it.

KenS · May 12, 2019

After a significant number of year's experience with a Wing-Lynch when a 'working' photographer before my retirement I decided to 'continue' so doing after. I first made my own tubes using black ABS tubes (not 'bad') but were 'useable' until I got a number of both 4x5 and 8x10 inch BTZS tubes... I have not done ANY tray or 'hangers-in-tanks' since.
I now 'finger-rotate' the tubes in a 'water-bath' using a "Tupperware' Container with water 'at temperature 'sitting' atop a folded towel om my 'bench' I 'change positions' of the tubes every minute... [Pyrocat HD is now the only film developer in my 'stable].. I make up my mine from 'scratch' chemicals using distilled water and chemical measured out using a much experienced
3-beam balance scale (and of course, distilled water). Yes... I still have my 'tanks' but they will not likely ever be used for developing/fixing again since they do come in somewhat 'handy for the 'washing'.

Ken

MattKing · May 12, 2019

Concerning C41 colour only...
If the OP is asking about twist agitation instead of inversion agitation, I would caution against it because it is difficult to obtain even development.
If the OP is asking about continuously rotating the developing tank on its side in a rotary processor, I note that Kodak datasheets do not recommend a different development time for rotary development vs. inversion agitation.

Sirius Glass · May 12, 2019

I have done both over a period of years and the Jobo processor wins every time with correctly processing and consistency.

Pioneer · May 12, 2019

Sirius Glass said:
I have done both over a period of years and the Jobo processor wins every time with correctly processing and consistency.

+1

Cholentpot · May 12, 2019

I do both, I have one tank that never leaks provided you burp it, although the blix always seems to leak a bit. The other tank I just swizzle. I've never seen a difference.

koraks · May 13, 2019

I've used the swizzle method for b&w work and also for color work in my early days of film development. I did not notice problems with uneven development. YMMV of course.

RalphLambrecht · May 13, 2019

Eric De Santiago said:
The instructions for my Cinestill C-41 kit say to use 4 inversion cycles every 30 seconds. I would rather do rotary agitation because the cap leaks when it’s upside down. What would the rotary equivalent of 4 inversions be?

some rotary processors indeed allow a switch in rotation direction but,I have only used (successfully) slow,constant rotation in one direction. the results were close to identical to inversion every60 seconds.

Rotary agitation instead of inversion

Eric De Santiago

pentaxuser

mshchem

AgX

KenS

MattKing

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Sirius Glass

Pioneer

Cholentpot

koraks

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RalphLambrecht

Rotary agitation instead of inversion

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