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Thread: Switching back to condensor head, 45MCRX, from cold light

  1. #1

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    Switching back to condensor head, 45MCRX, from cold light

    Ive been using my Beseler 45MCRX enlarger for over 30 years with a cold light. Seeing so many people using LED bulbs these days I was thinking of putting my condenser head back on with an LED bulb.

    The light chamber of the regular head has a semi gloss cone inside where the bulb is. My question is this....

    Should I paint the cone ultra flat black to reduce reflection or flat white to increase the light?

    will it make any difference painting it?



    edit... sorry I see this should have gone in Equipment.

  2. #2

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    Re: Switching back to condensor head, 45MCRX, from cold light

    Just curious, why use an LED bulb? Is the regular 212 not bright enough or is there some special result that is achieved with LED.

    I must admit, I like them in my flashlights, but I have a lifetime supply of 212s, and they are plenty bright enough for me.

    The interior of my CB7 and 45MXII condenser heads are white, as you describe, but the interior of my CB7 point light head (with a tiny bulb) is black. I have no idea why -- but an LED would be closer to the size of the PLS bulb. There must be a reason, so perhaps black will work better. That is just a guess. They both seem to create the same illumination edge to edge for me. Beseler must have done it for a reason.

    One point (ha,ha) to consider is, the point light source head is taller than the condenser head body. Again, I don't know why. Beseler must have done it for a reason.

  3. #3

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    Re: Switching back to condensor head, 45MCRX, from cold light

    So it's worked for 30 years and you feel a need to change it?

  4. #4

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    Re: Switching back to condensor head, 45MCRX, from cold light

    "One point (ha,ha) to consider is, the point light source head is taller than the condenser head body. Again, I don't know why. Beseler must have done it for a reason."
    The additional height is necessary in order to focus the light correctly for various sized prints.

  5. #5

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    Re: Switching back to condensor head, 45MCRX, from cold light

    That is what the adjustable condenser stage is for -- to focus the light correctly for various sized prints. You have not answered my question, nor have you offered an explanation. Have you ever actually used a Point Light Source?

    And how does that help Paul get it right about using an LED light(s) in his standard condenser assembly?

  6. #6

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    Re: Switching back to condensor head, 45MCRX, from cold light

    LED bulbs run cool. the physical bulb size are the same.

    yup 30 years of cold light. i love it, but im looking for that extra snap of condeners. i still have the cold light and can and will interchange them at random as i may chose for other situations or just may never use the one or the other ever again.

    i thought about white. it would reflect more light to the negatives.
    but black will reduce the reflected stray light and may give a better sharper print... i mean contrast boost.


    edit: why do this? because i can.

  7. #7

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    Re: Switching back to condensor head, 45MCRX, from cold light

    I had been only thinking of the tiny LED bulbs, not the "normal" size bulbs. That should work fine and I assume you can get one brighter, dimmer, or the same "wattage" output as the 212. If the "normal" size LED bulbs are like normal incandescent bulbs they will be imprinted on the top. Bulbs designed for enlargers have this info imprinted on the side instead so that it won't show up on the print!! Is that an issue with these LED bulbs? Also, I have read that LED bulbs have a different color spectrum (bluer?) than incandescent. With VC paper that might require adjustment. Others will know about this and chime in.

  8. #8

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    Re: Switching back to condensor head, 45MCRX, from cold light

    Quote Originally Posted by Paul Ron View Post
    i thought about white. it would reflect more light to the negatives.
    but black will reduce the reflected stray light and may give a better sharper print... i mean contrast boost.
    Interesting question. That might be why the interior of the point light source head is black instead of the normal condenser head. You could always run some tests first. One would be just try to use your condenser head with the regular 212 bulb (or what you have). As I recall the dimmer version is a 211. That might meet your needs. Another test would be to compare the condenser head as is vs painted black. That would take time and trouble -- especially if you find out the black version is not what you like. But paint in spray cans would make it easier.

    Have you already compared the results from the cold light and condenser heads? I know there is a difference, but some people consider it more substantial than others.

  9. #9
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    Re: Switching back to condensor head, 45MCRX, from cold light

    My one condenser enlarger projects the image of back-illuminated frosted disk, so bulb physical characteristics are not that important.
    However, most all other condenser enlargers project the image of the bulb. So the size, color and texture of the bulb will alter the projected image. Good thing is that nothing is occult, you will be able to detect uneven illumination easily with testing.

  10. #10

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    Re: Switching back to condensor head, 45MCRX, from cold light

    this all started because I decided to overhaul my enlarger, took her completely apart. I lubed and cleaned everything and went over the rollers n bearings. Now Ive got it back together doing the fine adjusts.

    I was intrigued about using LEDs after reading so much about it on APUG and here. The one reason I went to cold light 30 years ago was the heat issue. With LEDs running so cool, I felt it was time to try condensers again. Besides, I see lots of posts about condensers being a bit more contrasty. Its been a long time for me so I dont really remember the differences. But hey, Ive got time on my side to play with it.

    LED bulbs (at least the ones I have) dont have the writing on the end of the bulb, its on the bottom plastic flange. I have a nice choice of color temps and wattage to chose from. The bright white is much closer to a regular 212. But reading the 4000K responds better to VC papers. We'll see next week. If I had a prism to separate the color bands, I would be able to see a more realistic difference but I dont have a prism.

    I compared the light image of the 212 and the LED, they are both the same diameter and intensity. I did notice a shadow ring around the circles when holding the lamp house over the table before mounting it on the enlarger. I contributed the shadow ring to be reflections from the semi gloss black paint Beseler is using in the light box. Which got me thinking to paint it ultra flat black, which raised the question, WHITE OR BLACK.

    Im going to use white paper in the lamp house as an experiment to see if it makes any difference. I have a feeling I'll probably paint it flat black anyway.

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