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  1. #1

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    Gra-lab - Phosphorescence

    Hi. A little question I always meant to ask about the phosphorescent (glowing) numbers on the face of my good old Gra-lab (my dad bought it circa 1970 and it still keeps perfect time). I've always avoided using it in dark processes (printing, tray-developing film) because I assumed it would fog (particularly film). But at one time it was a pretty popular darkroom timer, so people must have used it in the dark. So what's the deal? Is it just not bright enough to fog paper within a reasonable amount of time? Etc.

    Thanks, Michael

  2. #2
    wildbill's Avatar
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    I think I'm on my fourth gra lab timer (all used). You're lucky!
    Mine fogs film nicely but not paper (three feet away). I made a flap out of show card that folds down over it when I'm loading/unloading film. If you aren't sure with your paper, just lay out a photogram for a few minutes and process the results.
    www.vinnywalsh.com

    I know what I want but I just don't know how to go about gettin' it.-Hendrix

  3. #3

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    The dark adapted human eye is very sensititive, far more sensitive than any phoitographic emulsion. What appears to us as being bright is not going to effect anything in the dark room. I have loaded film into a tank only to notice after I finished that there was enough illumination for me to see shapes around me. Never experienced any liight fog.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  4. #4
    RalphLambrecht's Avatar
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    mine is 4 feet away and has never fogged film or paper. it's too dim unless you place the glowing numbers right on top of the emulsion.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  5. #5

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    Interesting responses. I would have thought for sure it would fog film even if it was too dim for paper. I might have to test it and see what happens. It would certainly be great if I could tray-develop film with a timer I could actually see

  6. #6
    Mike Wilde's Avatar
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    I did have a time-o lite fog film at a distance of about 1' - 400 iso c-41 highly curly old film fighting to load it so on the dry desk in front f this timer for much longer than usual. I set it down to relax before trying to get it to load right, and ended up with shadowed sprocket holes printing onto the next layer on the reel.
    my real name, imagine that.

  7. #7

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    I place the Graylab 300 timer about 20” (about 50cm) above my developing trays on a shelf. The shelf overhangs the trays. The timer is high enough and far enough back on the shelf so that there is no direct line from any part of the phosphorescent face to the trays, yet the timer is still close and easy to see. Any light coming directly from the timer face towards the trays is intercepted by the forward part of the shelf.

    Apparently, whatever light reflects off of various surfaces is far too weak by the time it reaches the open try to have any effect on my films or papers. The fastest sheet film I use is ASA 320 or ASA 400 and is developed in the same trays as papers. I don’t see any fogging effect on these relatively fast films, which are likely more light sensitive than the papers.

  8. #8
    TheFlyingCamera's Avatar
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    So far I've had no problems with the Gra-Lab timers fogging anything, film or paper. To be on the safe side, I keep them a good 6' from my loading/printing area. And I have four of them up on the wall so that I can time multiple processes when printing (one for dev, one for stop/wash/fix/clear, one for second dev, etc).

  9. #9

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    I wonder if it can really be used when developing film in open trays vs loading film (developing obviously exposes the film for anywhere from 7 to 25 minutes in my case minutes before it is fixed).

    One thing that could help is the glowing fades pretty quickly on my Gra-lab, down to very dim but still visible levels. Presumably this is because it is 40+ years old.

    All these years I've developed sheet film without a visible timer, just a metronome and counting the minutes in my head!! Talk about adding stress to the process: "wait was I at 6 minutes or 7 minutes". It's like counting long rests when playing music. Stop concentrating for a few seconds and you're in trouble.
    Last edited by Michael R 1974; 11-30-2012 at 09:36 AM. Click to view previous post history.

  10. #10
    Shawn Dougherty's Avatar
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    I tray develop in front of mine, well, always. Never noticed any fogging from it. I used to turn it almost sideways against the wall but I couldn't tell a difference in the negatives so I just leave it as is.

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