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Jarita
29-Feb-2016, 11:25
Hello! I 'm new to the forum and need help. I just introduce myself in color printing , I am using a kit Tetenal RA-4 but all the pictures are colored cyan.
Someone can give me some clue about it ?? I find nothing in the instructions that help me

Thank you!: :)

Drew Wiley
29-Feb-2016, 11:29
This will need to be ironed out a step at a time. What is the setting on your colorhead? What kind of time/temp are you using for development? Are you certain
there is no cross-contamination between your chemicals? What method of development (tray versus drum etc), what specific type of paper? How fresh is your chemistry?

Jarita
29-Feb-2016, 11:53
I have done several tests with different values ​​in the colorhead and varied image contrast. I used the times and temperatures of the instructions 35Cº 45 ' ' developer and 1'00 ' ' the bleached fix, I even tried to give less time in the developer ( 30 ' ' ) and seems to improve a bit , but only a bit. I use a jobo minilab paper tray, and fuji crystal archive and chemicals are new, have a week


thanks for your time Drew Wiley

Drew Wiley
29-Feb-2016, 12:52
It could be blix contamination in the developer.

Jarita
29-Feb-2016, 14:27
the edges are not exposed are also cyan. The only thing I can think is that the paper this veiled or that the developer is contaminated, but the lamp is Ortholux jobo, could that be?

MartinP
29-Feb-2016, 16:17
Try to develop a sheet with no exposure and no safelighting -- that way you can eliminate a paper problem. If that paper is clean, then develop a piece of paper with no enlarger exposure just keep it on the easel for a few minutes with your safelight on. If that has a cast (and it is very likely at least part of the problem) then you know that you will need to move the safelight, change the safelight filter or (recommended) don't use a safelight.

Edit: If that Jobo is like the LED Durst Labolux safelight then there is an additional filter that is required for RA4 - possibly that filter might be missing? It lets out almost no light anyway, so just working in the dark should give the safest result.

agregov
29-Feb-2016, 16:33
Make sure you're not using the cyan color pack on your enlarger, it should be set to zero. You should only be using magenta or yellow. That said, appears that you're tray developing? Can't use a safelight unless it's color safe (which is very dim). It would be best to use a Jobo CPA/CPP processor and develop RA4 prints in drums. The Jobos can keep temperature exact. Bonus, you can develop negatives with the processor as well. More info on color in general here:

http://www.largeformatphotography.info/forum/showthread.php?55021-RA-4-Wet-Color-Is-it-worth-trying-for-a-newb

Drew Wiley
29-Feb-2016, 17:25
Ah.. a safelight?? No. This should be done in total darkness.

Duolab123
29-Feb-2016, 21:38
Ah.. a safelight?? No. This should be done in total darkness.

What Drew says. Get rid of any safelight, I use the Thomas Duplex safelight with the special color filter with no problems. Any ordinary safelight will fog color paper.

Duolab123
29-Feb-2016, 21:51
the edges are not exposed are also cyan. The only thing I can think is that the paper this veiled or that the developer is contaminated, but the lamp is Ortholux jobo, could that be?

Your safelight is for multigrade b&w paper and ortho film. It is NOT for color printing. You need to start over with paper that has NOT BEEN EXPOSED TO THE SAFELIGHT.

Work in total darkness.

Jarita
1-Mar-2016, 02:15
in a few days I go to the darkroom, I have really wanted to try new paper as it seems to be a question of safelight

thanks for your time you are generous! ;)

Wayne
1-Mar-2016, 07:34
in a few days I go to the darkroom, I have really wanted to try new paper as it seems to be a question of safelight

thanks for your time you are generous! ;)

You might need "new paper" if the box you have been using was opened under un-safelight.