View Full Version : Rodinal with rotary processing.. add EDTA salt?

16-Dec-2011, 13:08
Someone once told me that if I was to use Rodinal with a rotary process that I should add EDTA salt. Has anyone heard of this? Does it work and do you recommend it? Maybe the new formulas has this already added?

W K Longcor
16-Dec-2011, 13:52
Did the "someone" tell you why the suggestion of the addition? My own experience (from a decade ago) was with Rodinal in a Colenta rotary processor. I never modified the developer in any way - and always got excellent results.

16-Dec-2011, 13:59
Hi WK,
He added the EDTA salt to slow down the development in the rotary, because he said rodinal is not good at constant development. The reason I asked was to see if anyone had experience with this. I think I will just try the normal rodinal formula and subtract 15% for rotary process.

W K Longcor
21-Dec-2011, 18:49
As I said, My experience is from some time back. I ran my own test as far as processing times and dilutions -- and I am afraid I do not remember just what I used. I no doubt have a log of such tests -- but the paperwork is filed away -- just what box -- stored where -- I don't know. I do know that I did not add anything to the basic Rodinal formula -- and I got superior results -- perhaps as you say, by shortening time, or modifying dilution.

Eric Biggerstaff
21-Dec-2011, 20:57
My primary developer is Rodinal diluted 1 to 50 in a Jobo 3010 drum. I never add anything and the results are terrific.

26-Dec-2011, 11:12
Agree with Eric!

J. Fada
26-Dec-2011, 11:54
Ditto on the ditto.

Rodinal 1+50 in a 3010. I use a full liter of chemistry and the negs are perfectamundo. After about 5 years of struggling with all kinds of frustrating, infrequent odd issues with Pyrocat I am a happy camper.

I like a hefty neg so I don't cut the time at all.

26-Dec-2011, 16:45
Make sure you use 10 ml of Rodinal concentrate for each 8x10 sheet of film or equivalent (one 35mm roll, one 120 roll, four 4x5 sheets, etc).

If this results in too much liquid volume for your rotary drum, you must either reduce the amount of water, thereby changing the concentration, or reduce the number of films being processed simultaneously.

Rodinal has been my developer of choice for over 50 years. Before I got the Jobo I used regular stainless steel tanks and manual agitation.
I've processed hundreds of rolls of Agfapan in Rodinal using a Jobo CPE-2 with consistently excellent results.

I don't know what EDTA is, so obviously I've never used it.

- Leigh

Gary Tarbert
26-Dec-2011, 17:16
Rodinal 1to50 is also my soup of choice , i never add salt my doctor tells me it is bad for me:D Cheers Gary

26-Dec-2011, 17:21
It's actually supposed to be 1 + 50, yielding a total volume of 51, although the difference is rather insignificant at these dilutions.

- Leigh

27-Dec-2011, 05:11
I too had no issue at 1+ 50 mix w/ nothing added. I did lower my times a bit but eventually found that slightly longer times gave better negatives in sheet film. I never paid much attention to the 10ml per sheet of 810/roll of 35 as I had been using rodinal for a while before I knew that "rule". Once I found out I upped my amount of liquid. I did not see much if any difference but I follow that rule now.

I switched over to rollo pyro for LF negs for contact printing but the rodinal was easy, cheap with great results

27-Dec-2011, 06:10
I've heard of adding EDTA to pyro solutions in an attempt to reduce the massive degree of oxidation that occurs but never Rodinal.

27-Dec-2011, 13:28
I'm glad I heard these responses. I love rodinal and have used it for years but never with an expert 3010 drum and motor base (constant agitation). I will have to develop soon and see the results for myself.