RA4 Printing Problem
Has anyone any ideas what is causing what looks like a cyan coloured stain around the edges of my print. I am using Fuji CA paper and Kodak's Ektacolor Developer Replenisher RT/LU in a Nova heated slot processor at 35 degrees celcius. As well as the stain, the print itself has a muddy cast over it. This is the first time I have encountered this problem. I know its not a safe light problem as I didn't use one. I mixed fresh developer to see if that helped but the problem still exists.
I have had that problem.
The fix for me was to change my process to keep the solutions from getting contaminated.
I'm using a JOBO and reliably get 20 8x10s using 200ml.
The last ten seconds of each bath is draining.
Pre-rinse twice, 30" each clean water
Develop for time appropriate for the temp in use
Stop bath 30"
Rinse, clean water, 30"
Blix for the same time the developer got
Three 30" rinses in clean water
Blue stains can imply developer carryover into the blix, or fogging. Though you don't have a safelight, that doesn't mean your darkroom is safe - RA4 is pretty sensitive stuff so I would suggest doing a safety test by progressively covering a sheet with hard-edged things (coins, tanks, whatever).
To prevent carryover, the recommended way is to use at least one of a stop bath and/or rinse between developer and blix. My process looks like markbarendt's though I give it at least 2:00 of rinsing (as per Ektacolor specs) and 4 changes of water in that time.
I left one thing out.
I do add extra time as more sheets go through. So 1 minute is a normal start time for the temps I use, the first 6-8 sheets get that for both develop and blix, then the next 6-8 get 1:30, the balance maybe 2:00. I don't know if this extra time is needed, I haven't found the limit yet, but Kodak does advise extra time when you go past normal capacity.
Blix or hypo contamination of the developer, safelight fog or lack of a stop after development with inadequate blixing.
Thsse are 3 of the likely causes of cyan stain.
When I started colour printing (in the last century:D) I used a JOBO and got all descriptions of problems and probably the same as you are getting now. I changed over to a Nova Slot Processor and the problem disappeared. It WAS contamination caused by not washing and drying the drum out properly after each print. Doing it after each print was tedious and slow, the NOVA is much quicker and more reliable, you only have to rinse off the clips that hold the paper.
This problem happened from the first sheet of paper that went through the process. All chemicals were freshly mixed and there are no light leaks in my darkroom. I have never had this problem before so it really has me baffled. I doubt it is caused by dev carry over into the blix as I use a stop and also a rinse bath between them. Its strange that the stain is only on the edges of the paper although the cloudy dull cast is all over the print. I will mix fresh chemistry again and have another go at it.
Have you tried the pre-rinse?
No I have never pre-rinsed and never had this problem but I suppose it won't hurt to try it.
I had a similar, but not identical, problem that turned out to be bad, although newly purchased, paper. In addition to the staining like you mention, the paper base had a yellow cast.