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  1. #21
    Flotsam's Avatar
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    There has been mention of differences in the quality of condensor systems. I know that the function of a condensor system is to concentrate the light from the bulb evenly over the negative in it's carrier but beyond that, what characteristics would separate a "good" condensor head from a "not so good" condensor head?
    That is called grain. It is supposed to be there.
    =Neal W.=

  2. #22

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    Quote Originally Posted by Flotsam
    There has been mention of differences in the quality of condensor systems. I know that the function of a condensor system is to concentrate the light from the bulb evenly over the negative in it's carrier but beyond that, what characteristics would separate a "good" condensor head from a "not so good" condensor head?
    In addition to creating an even light source, there are other considerations that are even more important, in my opinion.

    The characteristics that seem to be of importance are the design and construction of the condensors themselves. Since these are in effect an additional optical system that affects the light quality prior to the light passing through the camera negative, one can see that the quality of this optical system is of importance. Involved with the design of these optical componants are such matters as the type of glass used, the optimal radius of the ground surfaces for the film format size, and the spacing of these componants.

    The condensors in a well designed system are responsible for focusing the light at the nodal point of the enlarging lens. This does not occur in a diffusion light source and may not occur precisely in a condensor system that is not properly designed.

    The cost of these condensors, as in most things optical, are expensive. I believe that I remember a figure of $25,000 on the condensor set for a Devere enlarger if one were to buy them today.

  3. #23

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    Thanks, everyone, for the replies. It's been most helpful.

    When I got serious about photography several years back, I did a lot of reading and research. Something that came up often was the opinion that as long as you've got a good enlarger lens, the rest of the enlarger was less important. Although the Jensen article was very biased towards condenser enlargers, it was a useful read, and certainly convinced me of the need to have a high quality, alignable condenser set. My current enlarger, an Omega B22, would appear to have no way to adjust the condensers or the lamp position.

    So, it's time to upgrade. Maybe that's where those elusive steely grays and luminous highlights are hiding! 8-)
    "If You Push Something Hard Enough, It Will fall over" - Fudd's First Law of Opposition

  4. #24

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    donald - which devere is 25 thousend ?
    good there are dursts and kaisers ... lol, not that they are cheap but at least u can justify their prices.
    victor

  5. #25
    Flotsam's Avatar
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    Quote Originally Posted by Donald Miller
    The cost of these condensors, as in most things optical, are expensive. I believe that I remember a figure of $25,000 on the condensor set for a Devere enlarger if one were to buy them today.
    In that case I don't think that I will purchase a second "back up" set just to keep on hand in case the first ones get fingerprints on them. :o
    That is called grain. It is supposed to be there.
    =Neal W.=

  6. #26
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    Quote Originally Posted by Flotsam
    There has been mention of differences in the quality of condensor systems. I know that the function of a condensor system is to concentrate the light from the bulb evenly over the negative in it's carrier but beyond that, what characteristics would separate a "good" condensor head from a "not so good" condensor head?
    As Donald stated below even distribution of light this is only part of the picture. Directed light means directed from the bulb right through the lens down to the baseboard. With directed light you are concerned about the light taking the right direction: Into the back of the enlarger lens and through its aperture. Diffuse light acts more like a shotgun here, sending the light in all directions thereby passing enough through the lens. A condenser-set must have the right focal length to send its light through the aperture of the enlarging-lens instead of bouncing it against the mount or the bellows and the right image circle to illuminate the respective negative.

    Not quite as "good" systems and (I'd better said "less collimated") work with more diffusion, white domes, closer/bigger opal-lamps to achieve even illumination with universal condensers, less collimation, less sharp grain, less obvious scratches/dust. Leitz Focomats or my former Dunco 66IISW are examples for such in-between constructions.

    The increase in contrast and apparently sharp grain (after adjusting contrast) when stepping form a Dunco with an universal condenser for 6x6 in a white mixing-box to a Durst L54 with dedicated condenser-sets for every focal length, all black inside, and a lamp quite distant from the negative stage was astonishing at least to the beginner I was at that time.

    My personal solution to the question is simple: have both and use them as subject matter and technique suggest. Used enlargers are to cheap these days to restrict myself.

    best

    Stefan

  7. #27

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    Hi doug,
    I tried this when I wanted a cold light head for my d5 but didn't have the funds to do so at the time( I finally got one from that well known auction site). Go to a plastic supply store and purchase a piece of translucent acrylic I tried a piece of 1/4" but an 1/8th would be better as it wouldn't absorb as much light. Get them to cut it just slightly larger than the condensors. Then when you get it home trace around the housing (condensor) and remove the circle of protective paper and remove the paper on the otherside then place this under the condensor and above the neg carrier. You may have to use electrical tape to mask off some of the stray light.
    Try making a print with the plastic in place.the light from the condensors will be even above the plastic which will then be diffused before it passes through the neg. if it works and print times aren't to long you can cut the plastic to fit permanently under the condensors. The price of the acrylic shold only be a couple of bucks.
    best regards
    Andy tymon

  8. #28
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    I had an interesting experience in my darkroom today. If any remember I had a negative I'd shot at Jekyll Island this spring that looked good scanned and tweaked but when I tried to print it the mid tones just muddied up and the detail got lost. I was using a dichroic head and Polycontrast RC paper.
    Well I just finally got my hands on a condensor head for my Beseler and also got some Ilford Warmtone fiberbase vc paper. With the jump in contrast I got from the condensor I put a no. 1 filter under the lens and the print came out looking nearly like what I posted in the gallery. I'd scan it to show what I got but it's 11x14, too big for the scanner bed. Any comments on this?
    Gary Beasley

  9. #29

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    Gary,

    Am I understanding you to say that the local contrast increased with the condensor light source? The change could be due to the paper. It could be due to the condenser.

  10. #30
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    Overall contrast increased, as expected. What was not so expected was the better separation of the midtones when I used a lower contrast. Is this an increase in local contrast? I know the details are a lot sharper looking and better defined.
    Gary Beasley

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