Gap Between 45S Beseler Head and Negative Carrier

Discussion in 'Darkroom Equipment' started by Neil Poulsen, Aug 13, 2009.

  1. Neil Poulsen

    Neil Poulsen Member

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    I don't have a Beseler enlarger. But, isn't it the case that there's a gap of an inch or so between the 45S diffusion glass and the negative? With the 45S being mounted above a filter drawer, I don't see how the diffusion glass could be any closer to the negative than about an inch higher.

    Assuming this gap exists, is this not a problem? Wouldn't there be significant light fall-off between the diffusion glass and a 4x5 negative? If not, why not?

    I ask, because I have a Type II Zone VI with the Beseler color head adapter, and the adapter is thick enough that the diffusion glass can't reach the negative. It finally occurred to me that this gap is probably similar to my conjectured gap with a 45S mounted on a Beseler enlarger. As I say, I wonder if this wouldn't lead to uneven coverage, too much light fall-off at the corners, etc.
     
  2. Whiteymorange

    Whiteymorange Member

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    I don't see how the space between the negative and the diffusion glass could be a problem. Think of that space as the light mixing chamber. Since this space is not variable, the quantity of light coming through the negative is not going to change and the only real light fall off comes as the distance between the negative and the paper changes. I've never had a problem with the cold head on a Beseler 45 nor have I had any with the color head.
     
  3. Neil Poulsen

    Neil Poulsen Member

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    Thanks for your response. Can you print 35mm film using your color head? Do you have long exposure times?

    I've also had occasion to use the 45S head where it rests right on the negative carrier, and there was no problem whatsoever printing a 35mm negative. Very fast.
     
  4. Whiteymorange

    Whiteymorange Member

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    I've only worked in 6x6 and 4x5 with the color head, since I put it on a school enlarger kindd of lare in the year and haven't had much time in the darkroom this summer. My memory is that the exposure times were in line with the cold head, maybe a little faster. Sorry, didn't take notes.