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  1. #11

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    There is not a wiring problem if you use the tungsten bulbs originally intended for this printer. They were wired in series to cut down their output, and to ensure the printer did not light up if one bulb was burned out. If you must use the compact flourescent bulbs, you wil have to rewire in parallel, and your wiring diagram shows both wires shorted out at the switch. In truth, only one side of the electric service needs to go thru the switch. So, to verbalize it. One unswitched lead from 110v service needs to go to one terminal on each socket. Another lead (from the switched side of the 110v service) needs to go to the other terminal on each socket. You may find that with the CFL bulbs your exposure times are too short for modern enlarging paper.

  2. #12
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    I wouldn't blame CFL's for anything, but they are the wrong thing for this tool.

    I would say they are unlikely to work in a satifactory way in this type of printer. The exposures will be far to short for the CFL type bulb to even out into any type of consistency, even warmed up, because they are many many times too bright for modern paper, in this type of printer. (Unless you have a AZO stash, and you'd be nuts to wreck a bunch of AZO tying to make the CFL's work.) My "experiments" with CFL's in a diffusion enlarger also indicate uneven spectral distribution that mimics the spiral of the bulb, a sort of spectral phasing that casts alternating green and magenta spirals, so contrast will be all over the place on the same print with VC papers, even if you could get them on and off in a consistent predictable way, if your experience turns out like mine. The proximity of the bulbs to the diffuser in the contact box will likely exacerbate that problem. I found that I could get the CFL to come on in an "sort of" predicable manner if I pre-burned them for a few minutes, and struck the lamp within about thirty seconds. Not much time to get paper in and adjusted, and if you don't make it, you get to put the paper back and start over. (except these bulbs are gonna fry your paper anyway, unless your negatives look like a welders mask)

    Not worth the PIA,even in an enlarger, where the output power was at least in a useful range.

    Find 7.5w tungstens, and double diffuse, as suggested, or look into LED. The small output of an LED might be ideal in this application, and since you can get them in edison base, and you can get them in colors, and your going to rewire it, you could have two switches, one for green, and one for blue, and have a ready made split printer.

    That's what I'd do. (Unless I'd been drinking)
    Last edited by JBrunner; 01-24-2008 at 11:15 PM. Click to view previous post history.

  3. #13
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    Quote Originally Posted by copake_ham View Post
    Blaming CFLs is a red herring. Whether or not you use CFL's or incadescents - it seems there is a wiring problem.

    Which type of bulb is in the socket is immaterial once the CFLs warm to full light.

    I would first check the efficacy of your switch and also replace the main plug and wire. To begin with, they look like fire hazards.

    There's a reason that thing was stuck into the basement to begin with - and it was problem long ago - certainly long before there were CFLs.
    There isn't a wiring problem, it was made to run half voltage to two incandecent lamps.

    The bulb type isn't immatierial for photographic printing. There are many factors at work, including spectrum. See my post above.The idea that this type of bulb can be a direct replacement in all applications is the red herring.

  4. #14
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    Quote Originally Posted by JBrunner View Post
    There isn't a wiring problem, it was made to run half voltage to two incandecent lamps.

    The bulb type isn't immatierial for photographic printing. There are many factors at work, including spectrum. See my post above.The idea that this type of bulb can be a direct replacement in all applications is the red herring.
    You do have a point on both counts, and remembering how Florescents work that does raise a concern for short-period exposure on photographic paper.

    I'll likely go the route you mentioned lower wattage conventional bulbs (like 25 or so that they'd go half at 12 or so) Course if I go LED I'll redo the wiring completely and put those lights directly on the bottom of the box facing up but either route would work for the additional diffusing panel I was taking about because I want to experiment with the idea my co-worker came up with in terms of dodging contact prints by laying shapes down on the lower diffusion board.
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  5. #15

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    Quote Originally Posted by kb244 View Post
    I want to experiment with the idea my co-worker came up with in terms of dodging contact prints by laying shapes down on the lower diffusion board.
    That is no experiment, it is a proven technique for contact prints made on a contact printer.

    There was at one time (newer than your machine) a super-deluxe volume production contact printer that had a whole bank of small lights, each one with its separate on-off switch, the idea being that you could adjust the exposure across the LF negative to give dodging and burning effects. Say you needed more exposure in the sky, you would leave those lights on full, and say, possibly switch off every other light on the rest of the negative area. Of course the whole light source of many small bulbs was diffused thru an opal glass, upon which you could also lay dodging papers, as this was below the glass plate you put the negative on. Quite a machine.

  6. #16
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    Quote Originally Posted by PHOTOTONE View Post
    That is no experiment, it is a proven technique for contact prints made on a contact printer.

    There was at one time (newer than your machine) a super-deluxe volume production contact printer that had a whole bank of small lights, each one with its separate on-off switch, the idea being that you could adjust the exposure across the LF negative to give dodging and burning effects. Say you needed more exposure in the sky, you would leave those lights on full, and say, possibly switch off every other light on the rest of the negative area. Of course the whole light source of many small bulbs was diffused thru an opal glass, upon which you could also lay dodging papers, as this was below the glass plate you put the negative on. Quite a machine.
    :P Technically its an experiment for me if I am making sure I actually do it right
    -Karl Blessing
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    The Bokeh
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  7. #17

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    I believe that Stouffer Technologies in South Bend, Indiana still makes these contact printers.

  8. #18
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    Quote Originally Posted by BobNewYork View Post
    I believe that Stouffer Technologies in South Bend, Indiana still makes these contact printers.
    :P Probably for more than I want to spend too But actually nice to know they're available new.
    -Karl Blessing
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    The Bokeh
    Color Film always existed. It's just the world was always black and white till recently.

  9. #19
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    Quote Originally Posted by kb244 View Post
    what I want to do is put four pegs in the corner down near the bulbs and drop in a larger peice of frosted glass in hoping of diffusing the light even further before hitting the negative.
    Another way to make it more even is to get the diffuser closer to the negative. The less the center of the negative can 'see' of the edges of the diffuser, the better.

    BTW there is a very cool 'doging' contact printer on e-bay. (item no. 150215888469) It has been listed for quite a few months but I couldn't get the guy to come down from $650. I thought this would be a great project to make the ultimate VC contact printer but wound up getting an 8x10 enlarger instead.

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