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Thread: Dektol dilution recommendation for overexposed negs? (16x20 prints)

  1. #11

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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Quote Originally Posted by Bernard_L View Post
    Except ordinary white LED bulbs have a poor CRI, meaning that even if they claim some color temperature, their spectrum is different from a tungsten bulb. In summary, will probably work, but expect some adjustments of multigrade filtering compared with a tungsten source.
    It works perfectly for me, if not using a high CRI white (of same K) there is a need for adjustements in the grade, as was the case for cold cathode illuminations. You may recall that cold cathode illuminators also had remarkable corrections.

    I've been using an RGB LED bulb for contact copy split grade. With the remote command I switch Red safe light, green and Blue, I've pending making an accurate calibration for RGB grades because I'm making a LED retrofit for a 138S.

  2. #12
    ic-racer's Avatar
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

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    If the enlarger lamp is old, sometimes the filament or the reflector can deteriorate. Try a new lamp.

    Otherwise if you are printing on multigrade paper try these values instead of the values containing neutral density. This table will give you the shortest printing times.

    You can also burn with white light instead of green (yellow) for the highlights..
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  3. #13
    ic-racer's Avatar
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Quote Originally Posted by Michael Graves View Post
    Are you using the 4x5 mixing box on the enlarger? Not doing so may result in lower light output.
    Unfortunately the 4x5 mixing box is the dimmest. But that is the only one he can use for 4x5 negatives.

  4. #14
    ic-racer's Avatar
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Finally what I would do is replacing the original tungsten bulb by a led source (a powerful led bulb, perhaps) sporting x10 times more effective light power.
    Why post an impossible solution for a beginner? This will only lead to 'internet confusion.' There are no 82 volt LED replacements are available for that enlarger. The wrong lamp may void the warranty and may destroy the power supply; this is a $6000 enlarger that the OP does not own.

  5. #15

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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Changing your print developer solution isn't going to help much. Dektol at 1:1 is already quite strong. You need to see what the problem is with print exposure. Check you light source, mixing box, filters, etc. etc. If indeed all is optimal, then you'll just have to live with long exposure times. However I find it a stretch to think that even a 3-stop overexposed negative would require three whole minutes of exposure under a properly set-up enlarger.

    Best,

    Doremus

  6. #16
    Jac@stafford.net's Avatar
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Try an experiment: if your negative is very overexposed, make a contact print exposed enough to actually make a print. You might be surprised if your over-exposure pushed the density far enough up the curve that it met the shoulder and down the other side. Never mind if you are using T-Grain film.

  7. #17

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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Quote Originally Posted by Doremus Scudder View Post
    Changing your print developer solution isn't going to help much. Dektol at 1:1 is already quite strong. You need to see what the problem is with print exposure. Check you light source, mixing box, filters, etc. etc. If indeed all is optimal, then you'll just have to live with long exposure times. However I find it a stretch to think that even a 3-stop overexposed negative would require three whole minutes of exposure under a properly set-up enlarger.

    Best,

    Doremus
    Thank you, sir. Yeah, does it even sound normal to having to make a print exposure around 5-7 mins at f8 at the most dense highlights and 1.5 mins at the midtone/shadows (1 stop from wide open). I don't think the school uses a mixing box (just having looked what a mixing box is on the internet). I don't think I severely overexpose my negatives during the negative process.

    The connection with having a well exposed negative and translating to the printing process (with having consistent ballpark printing times) is something I'm trying to figure out.

  8. #18
    おせわに なります! Andrew O'Neill's Avatar
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    There are a few ways to print that negative, but if you are a beginner, you should first work towards easily printable negatives. Your print by the way, looks fine. Once you are a seasoned darkroom printer, you can always come back and print it, trying something like pre-flash...

  9. #19

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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    Based on your description of how you exposed your negative using an orange filter, f45 and a 10 second exposure, I think you may have grossly over exposed the negative. I think the correct exposure should have been closer to 1/2 second or 1 second at F45. You might also want to check to make sure the knob on the head that cuts the enlarger light by about 2.5 stops is not engaged.

  10. #20
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    Re: Dektol dilution recommendation for overexposed negs? (16x20 prints)

    sounds like a great candidate for contact printing with a 300R bulb to me

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