What on earth is a Durst Luxoneg?

Discussion in 'Darkroom Equipment' started by Cybertrash, Dec 5, 2013.

  1. Cybertrash

    Cybertrash Member

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    When I bought my darkroom equipment I received some kind of contraption called a "Durst Luxoneg", and I can't quite figure out what it's supposed to do. It looks like this (picture not mine). It appears to be some sort of exposure meter for enlarging, but I can't figure out how to operate it, nor have I been able to find any sort of manual online.
     
  2. horacekenneth

    horacekenneth Member

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  3. dmb

    dmb Member

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    It works in a silimar fashion to the Ilford EM10 meter. You setup a representative negative in enlarger and find a good print time using test strips. Then without changing aperture and with safelight OFF place the sensor under a light part of the image (ideally you are selecting a part that you want to be shadow with a hint of texture) press button on side to turn on (it needs a battery) - turn dial - there are two red lights and one green - note reading when green light shows - this is your paper speed - write it on the paper box along with exposure time you found. To print another neg perhaps at a different enlargement, with safelight off, set the dial to the right speed for paper, open up enlarger lens to widest aperture, place sensor under a light part (same idea looking for a shadow with slight detail) press button on side and adjust aperture until green light appears - your exposure time will be about the same as you wrote down. I use my EM10 to get me in the ballpark for exposure time and then use small test strips to fine tune.

    I think as no green light on this it would be when both red lights on !
     
  4. Cybertrash

    Cybertrash Member

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    I see, that's pretty nifty, could probably reduce the amount of test strips I'd have to do. I suppose I should do the calibration at a 'normal' contrast (grade 2 or 3), but which aperture would I use when I'm doing the calibration print? Wide-open? All the way stopped down?
     
  5. polyglot

    polyglot Member

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    It doesn't really matter, especially if you're not changing enlargement ratio. The meter measures the light hitting the paper; it doesn't matter how it got there. You're recording a light intensity (metered) and exposure time for future use; when you come to print in future you just set up the exact same conditions (intensity and duration), maybe with a time/aperture tradeoff so that you can work near a desirable aperture.

    For practical purposes if you make the measurement with a small print, you probably want to do the metering at a small aperture. That way when you do a big print (with dimmer light from the enlarger), you don't run out of lens speed trying to get the meter to read correctly.
     
  6. paul ron

    paul ron Member

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    I have a similar gizmo... It has a neon light that will go off like a null meter dial. I calibrate it each session n set for my first black... Usually the margin of the neg n include a small part of my image as reference. It gives me a good starting exposure.. Then i'd still have to work my print for local details n contrast anyway. It just takes some of guesswork out of it.

    I stopped using it in 1980.... Just got tired of calibrating n noiw just dive right in with my gut feelings.
     
  7. Cybertrash

    Cybertrash Member

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    I just tried calibrating it after making a print, but I couldn't get both LEDs to light up, I settled for one of the LEDs lit and the other one sorta flickering, not sure if it'll prove to be a reliable reference point, but we'll see.