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  1. #1

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    RA4 has gone bright yellow!

    I've been having some problems with RA4 printing that I've never had before. I'm using a Nova 4-slot heated processor, Tetenal RA4 chemicals and Fuji Crystal Archive paper, at 22C.

    First, I noticed that there were what seemed to be cyan 'splash marks' appearing at various locations on the surface of the print, so decided to give the tank slots a good clean in case there was contamination of some sort.

    I soaked the slots in a dilute solution of household bleach for 24 hours (others seem to have tried this with no apparent problems). The top of the developer slot still looked rather mucky so I tried some Muc-Off bike cleaning spray (a biodegradable alkaline solution - perhaps similar to Nova Tarbuster) that seemed to work well. After many rinses and standing with fresh water in the slots for 24 hours, I then drained the slots and re-filled with the existing chemicals - maybe not the best idea.

    Now I find that the prints are almost completely white but with a pale yellow image discernable in the darker parts. There are also still marks that look similar in shape to the 'cyan splashes' that I had previously, except this time they are pale yellow.

    Does anybody else have any experience of this, or know what might be going on?

    All advice gratefully received!

    Thanks,

    Edward.

  2. #2

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    Hi Edward,

    Seems there's two issues here. Firstly the cyan marks and then the almost white/yellow prints. I think I'd try to tackle each at a time and I'd firstly look at the white/yellow print issue which seems to have been caused by the bleach (presumably no other things have changed). Maybe the Nova needs another good wash and then fresh chemicals, Work on this problem before going onto the cyan splash problem which may be an issue with the Tetenal kit - another member here had some big problems with the blix.
    Steve.

  3. #3

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    I don't think I am clear on what you see but I think you are saying that the prints are almost normal but with some yellowness in the shadow areas? Have I got this correct? You are not saying that there is almost no print discernible on the paper but there is an overall yellowness in fact a brigh yellow according to your headline? An attached scan of the prints in question might help

    I find it difficult to believe that dilute bleach which has been flushed out could affect the paper to that extent. I take it that the exact same paper was printing fine until the bleach clean-up?

    To eliminate the paper as a problem try developing in a tray or any container that hasn't been cleaned with bleach. If it prints OK then it suggests that the paper and chemicals are fine and there has been contamination in the Nova.

    Try using a stiff bottle brush with running water through the slot from the top, giving it a vigorous scrub including along the bottom of the slot and letting the water flow out of the bottom taps. It might just be that that there is remnants of the bleach at the bottom of the slot which has mixed with the chemicals. Use plenty of water and elbow grease. Then refill the slots.

    I use dilute bleach in my Nova and have never experienced a problem with B&W chems but they may not react the same, I don't know.

    Cyan streaks was what I got if I failed to dry our a Jobo drum properly. Even a small remnant of water running across the print before being diluted with developer gives a cyan streak. Could there be any way that plain water has touched the paper surface? Just a thought.

    If any of the ideas submitted here cure the problem be sure to let us know.

    pentaxuser

  4. #4

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    Thanks for your replies!

    I'm attempting to attach a before-and-after scan to show what I mean (never tried this before so I hope it works!).

    The top section shows a test strip on which I have marked the 'cyan splashes' with arrows - I hope they show up after being shrunk and converted to jpeg. The white area at left is the shadow of a hand holding the paper. Please also note the 'flame' effect along that edge (which was towards the bottom of the Nova slot) and also a similar effect along the wavy edge, which had been cut with scissors in the dark.

    The bottom section shows the result after cleaning the tank: this time a single exposure of 20 seconds - about twice the length of the longest test strip time. The arrows show a mark that may be caused by the waffle pattern of the tank wall, perhaps? Previously, these marks were appearing as cyan before I cleaned all the tank slots (although there isn't a waffle mark in the top section on that particular test strip).

    I suppose I must have failed to rinse the slots sufficiently after cleaning, but I'd still like to know the cause of the 'cyan splashes' which I have not had trouble with before.
    Attached Thumbnails Attached Thumbnails bright_yellow.jpg  

  5. #5

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    Thanks for that I now can see what you mean. Yes , it is one colour only and a very faded picture. If it is caused by dilute household bleach contaminating the developer then given there is 1L of dev in the slot and the dilute bleach has been further diluted and drained away then household bleach even in minute and very highly diluted quantities must be devastating stuff. So devastating that any RA4 users of a Nova should steer clear of any household bleach at all.

    As you may have gathered from the above I still remain doubtful that at very high dilutions and flushing, such bleach remains the culprit.

    Maybe photo chemical engineers will add a response. I hope PE and other knowledgeable experts can shed some light on this.

    When you do the scrubbing you might want to drain the water jackets first and tip Nova at an angle so the water going into the top is all running out at the bottom and then to make sure the empty slot is dry I'd use a hairdryer with a narrow blower to ensure the slot is bone dry before filling up.

    pentaxuser

  6. #6
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    Color chemicals are extremely susceptible to contamination.
    I have gotten cyan splash marks if my hands were wet from my wash tray right before I grabbed a fresh sheet of paper to expose.

  7. #7

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    I hope you solve your problem because that picture looks like it's got great potential.
    Steve.

  8. #8
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    Hypochlorite bleach is recommended for cleaning tanks in professional labs by chemical manufacturers so I don't believe it's so highly contaminant. Of course you must give a very good wash anyway, so I don't rule it out as one possibility. And in fact it's hard to see any other possibilities from what you mention.

    Very weird. I have never had a slightest problem with RA-4 developer, -- except a case when the concentrates went bad in keeping much faster than any working solution --

    but no color splashes, no "fading", and my procedures are a bit sloppy every now and then. Even a year-old working solution works perfectly. So I'd say; very weird.

    And I can't find a reason why the color developer would be especially susceptible to contamination. Never seen it, never heard a reason why it would be so. Have done reversal RA-4 with a BW developer as a first step with quick wash in-between, no problems...

  9. #9

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    Taking note of advice earlier in this thread, I ditched the existing chemicals and gave the Nova tank another clean with a scrubbing brush and rinsed it thoroughly with copious amounts of running water (in the bath, with the shower hose!).

    Then I made up new working solutions from the same bottles of concentrate as the first attempt and had another go at printing. This time, the prints came out dark blue. So I re-did the colour calibration and have now ended up with 'perfect' prints, using exactly the same filter settings as I was using at the start of the year with a different box of paper.

    So I have to conclude that the first batch of working solution was not right at all, for whatever reason, and maybe remnants of the initial cleaning process were sufficient to finish it off completely (this is all just a guess really, I'm not a chemist).

    As for the 'cyan splashes' on the original test strips, I wonder if these were caused by touching the surface of the paper. The darkroom is in an unheated garage (but an integral part of the house) and was really quite cold last week. Usually I bring the paper into the house to warm it a bit before printing, but I forgot last week and I wonder whether the cold, gloss surface attracted some condensation in the same way that placing fingers close to a cold glass surface can sometimes do.

    So the problem has gone away, even if the mystery isn't completely solved. I guess the moral of the story is to rinse very thoroughly indeed after cleaning Nova tanks!

  10. #10

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    Thanks for that. I think this shows that 1. Bleach can be used if properly cleaned out and
    2. If in any doubt change the chemicals and maybe be prepared to re-calibrate.

    I still think that colour work in the sense of calibration and chemicals is more difficult that B&W but on the other hand, once you have got it right then prints may be done with much less manipulation and a complete run can be done with little variation so the same number of prints might be printed more quickly in colour than B&W.

    pentaxuser



 

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