Magenta casts in RA4

UF_labtech · Oct 1, 2008

This is my first post on APUG so be gentle. Also, I hope I am not asking a question that has been thoroughly discussed; I did a search but did not find a thread about this. I have been experiencing some problems working with Kodak Ektacolor RA Developer Replenisher RT and Ektacolor RA Bleach-Fix. I run a Kreonite KMIV processor (huge machine prints 40" wide). I run a replenishment rate of 40mL/sq ft for both the developer and blix. Also, I only mix up 2-3 gallons of replenisher at a time to try and keep oxidation down. This replenisher stays in nalgene tanks with floating lids. I would say that an average day of usage would entail about 50 11x14s being run through the processor and this would be about 3-4 times a week.

Now the problem I am having is my whites are a dingy pinkish/magenta color. If I take a sheet of unexposed paper and run it through that is the cast I get on the whole thing. The only explanation I can gather is that my developer is oxidized and this is causing my pink/magenta whites. If this is indeed the case what would I do to counteract this? Do I boost my replenishment rates, and if so how much? I am running at the "suggested" replenishment rate but I have no idea what that is taking into account. This processor does not have nearly enough prints going through it to keep it running properly I suppose but I need to find a way to remedy this magenta malady I am having. I thank you in advance for any advice.

bob100684 · Oct 1, 2008

UF_labtech said:
This is my first post on APUG so be gentle. Also, I hope I am not asking a question that has been thoroughly discussed; I did a search but did not find a thread about this. I have been experiencing some problems working with Kodak Ektacolor RA Developer Replenisher RT and Ektacolor RA Bleach-Fix. I run a Kreonite KMIV processor (huge machine prints 40" wide). I run a replenishment rate of 40mL/sq ft for both the developer and blix. Also, I only mix up 2-3 gallons of replenisher at a time to try and keep oxidation down. This replenisher stays in nalgene tanks with floating lids. I would say that an average day of usage would entail about 50 11x14s being run through the processor and this would be about 3-4 times a week.

Now the problem I am having is my whites are a dingy pinkish/magenta color. If I take a sheet of unexposed paper and run it through that is the cast I get on the whole thing. The only explanation I can gather is that my developer is oxidized and this is causing my pink/magenta whites. If this is indeed the case what would I do to counteract this? Do I boost my replenishment rates, and if so how much? I am running at the "suggested" replenishment rate but I have no idea what that is taking into account. This processor does not have nearly enough prints going through it to keep it running properly I suppose but I need to find a way to remedy this magenta malady I am having. I thank you in advance for any advice.

Any chance your paper is fogged or getting old?

UF_labtech · Oct 1, 2008

This problem happens with every paper I and my students have put through be it Kodak or Fuji. The paper is as fresh as I can get it.

Thanks for the reply.

Photo Engineer · Oct 1, 2008

Try a stop bath after the developer. Kodak has that noted in its trouble shooting information for RA4. Looks like there is carryover of developer into the blix.

If that does not fix it, add about 5 g/l Na2SO3 to the blix in addition to the stop. The sulfite in your blix is oxidizing.

PE

Bill Edwards · Oct 1, 2008

Things to check

I have a list of things to check when I get a strange problem, 1) Does the problem go away if you change out the chemistry - don't forget the bleach? 2) Are the top socks clean? Do you clean them every night at shutdown? 3) Check the physical parameters temp, time and actual replenishment rate. If you have control strips is the process otherwise in control?
4)Double check your mixing routine with your current batch of chemistry. The same brand and specification as you thought you were using? 5) Are the exit socks still good- does the print come out of the developer tank with too much developer on it?

Ultimately magenta staining is an oxidation problem and low untilization does not help but it could be from excess carry over into the bleach, low replenishment or just lack of cleanliness. If the problem goes away when you change out chemistry and then slowly comes back try increasing replenishment rate to turn the tank solution more quickly. Once you get the stain the chemistry is very hard to recover. The bleach is just as likely to be the problem as the developer.

I will guess you are using Kodak chemistry. The only time I have tangled with magenta yuk is with Kodak but any chemistry could do it. You may want to try Trebla in my experience it runs cleaner and behaves better. The best stuff I ever used was Agfa (R.I.P.). I have run all sorts of machines up to 80".

Good luck.

Film until they cut it from my cold dead fingers!!

UF_labtech · Oct 2, 2008

Thanks!

Ok so I have one more question then. I have four tanks in this processor: Developer, Blix, and two stabilizers. I am only running it like this because this is how the guy before me did it. Could I do a Developer, Stop, Blix, Stabilizer setup or would that not work? If I cannot change to just one stabilizer tank would just adding the NA2SO3 be a viable option?

Also, in reply to Bill Edwards. If I just mix up brand new chemistry the problem is still there just not nearly as bad. The socks are clean and we clean them every night when we shut down the processor. The parameters are where they should be and I check, double check then have someone else check to make sure I have been mixing everything correctly. I think that if I can add a stop bath to the process I am going to drain the chemistry and start fresh.

Again I thank all of your guy's input and am going to see if I can make this right.

Photo Engineer · Oct 2, 2008

Well, actually, you might try a wash in there. Sounds like it might even be retained blix. With no wash, the pink color of the blix might carry through. To check this out, remove a sample of the paper from the blix and wash it well and then continue the stabilzer. Also, check the stabilzer tanks for coloration. They should not be pink.

PE

Bill Edwards · Oct 2, 2008

Since the problem is still there with fresh chemistry its got to be either carry over from a worn out (matted down) exit sock on the developer rack or something as simple as a worn hold down tab for the roller. The other choice is to try different chemistry.

Reconfiguring the processor is impractically large project and I don't think there would be sufficient wash/ stab time if you did.

Sulfite to the bleach can't hurt but probably wont help either. I have never exactly trusted the stab configuration and I've never had the magenta yuks with a water wash setup but that could be coincidence.

If you can make the room where the chem section is dark you can remove the cross over and catch a print as it changes tank from dev to bleach then put it in fresh bleach or stop then bleach in a tray to determin weather the developer is part of the problem or not. If the bypassed print is white it isn't the dev. Same with the stab only you can time when to open the machine and dispense with the darkness, catch the print and wash. That way you'll know where the problem lies.

If all else fails try a ring of salt around the machine mixed with some chicken blood (kidding)

UF_labtech · Oct 2, 2008

I am going to try each of your guy's suggestions to try and narrow down the problem here in 45 minutes when the students are done in that room.

Also, the students have complained about slipping on the blood from the offerings I have already made to the Kreonite overlords. lol

Thanks again.

frotog · Oct 2, 2008

I would not use stop bath if I were you as then you'd only have a one bath, 45" wash in stabilizer. That would be nuts. Blix carryover in your stabilizer will turn your stabilizer bath yellow, not pink.

Because you're using a washless system w/ stabilizer you could be running into silver sulfide buildup on your stabilizer racks. There's a kodak CIS 167 manual available as a pdf that describes how to treat this buildup with bleach wash followed by hypo. Most manuals will refer to a brown cast in the midtones but I've seen it as a magenta cast in many of the modern RA papers. There's also a product by hydra called "fury" that will remove silver sulfide buildup. Hope this helps.

Photo Engineer · Oct 2, 2008

Actually, the pink stain found in many cases of the sequence Dev, Blix... It is due to fogging and development in the blix if the ph goes over about 6.7, if the sulfite drops from below about 5 g/l or the excess chelating agent such as EDTA drops below a fixed level. Each case gives a slightly different pink stain.

1. Retained developing agent turns pink in air.
2. Ferric Oxide precipitate causes pink color even at 1 mg/square foot
3. Blix pH too high allows development to continue with fixer, like a monobath, and pink fog takes place.
4. Retained green sensitizing dye or acutance dye stains pink.

Check as follows:

1. check blix pH and adjust if needed must be about 6.2 - 6.5 and 6.7 is the upper limit.
2. check by washing after blix and inspecting for stain if not there, then blix is problem.
3. check by washing after blix and then stabilzing. If gone, blix is problem, but if there stabilizer is problem.
4. check by stop after developer and then do normal process, if gone then you must use stop
5. If none of the above, adjust blix pH to 6.2 and add 10 g/l Sodium Sulfite and 10 g/l Na2EDTA and check again.

The clue here is that it takes place with Kodak and Fuji papers, so it is the process.

PE

glbeas · Oct 5, 2008

PE what do you use to check the ph? I'm having the same problem with an ACP 200 with fresh chemicals. I can't get a balance on the colors for anything, even tried putting a room light exposed sheet through and it came out a mahogany brown instead of black. I'm wondering if the paper may be bad but I pulled it out of the fridge the same day. Thoughts?

Photo Engineer · Oct 5, 2008

I use a pH meter.

But with your problem, getting brown instead of black wiht a fogged sheet sounds like a developer problem. Low temp, low pH or short times will ruin the blacks.

pH = 10.5, Temp = what is given in directions and same for time. Check with 2 thermometers.

Blix in developer can cause the same type of problem as can too much sulfite. I would have no clue how you would get sulfite into the developer though, but that is a possible answer.

PE

Magenta casts in RA4

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