cold light head "color"

Discussion in 'Darkroom Equipment' started by Dan Dozer, Aug 1, 2009.

  1. Dan Dozer

    Dan Dozer Subscriber

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    Does anyone know the differences in performance between the different light units available from Aristo for B&W printing (VC Fiber paper)? Their website lists Cyan Blue, Blue White, Daylight White, and Warm White as all appropriate for B&W work, but they have wide variances in wave length. I assume that different wavelength (color) light sources are better for different types of paper/printing.
     
  2. George Collier

    George Collier Member

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    The new V54 lamp (cyanish in color) was developed for use with VC papers. Previous lamps could not be used with VC without extensive color correction filters added to the contrast filter.
    I use the V54 exclusively with VC papers (Ilford MGIV, now that Forte is gone) and I find I have to use lower filter numbers than I would have with graded paper for the same results, but the results are great.
    They offer a dual lamp version, for a lot more money, that uses a dialed balance of the two lamps to control contrast, more convenient, but they will admit to you that the single lamp (with a filter drawer - entirely different head, and a lot cheaper) is faster (brighter). I use the single lamp, and I bought 2 extra filter holders so that I can swop them more quickly when printing split filter combinations.
    If you do a search under "V54" and "Aristo head" in this forum and the Enlarging forum, you will find other info.
     
  3. ic-racer

    ic-racer Member

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    I was testing my W45 coldlight last night with a color meter. With a 30cc Rosco filter in place, I found it to be within 10cc of the incandescent 'white' unfiltered light from an OMEGA dichroic head.
     
  4. Lee L

    Lee L Member

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    Which color 30CC Rosco, and off 10CC in which color? Just curious.

    Thanks,
    Lee
     
  5. ic-racer

    ic-racer Member

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    Color probe nulled to Aristo W45 + 30ccY then placed under Omega Dichro head and it required M5 and Y0 to Null.

    Color probe nulled to Aristo W45 + 30ccY AND Ilford 00 filter then placed under Omega Dichro head and it required M0 Y96 to Null.

    Color probe nulled to Aristo W45 + 30ccY AND Ilford 5 filter then placed under Omega Dichro head and it required M65 Y0 to Null.
     
  6. Lee L

    Lee L Member

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    ic,

    Thanks for the data.

    Lee