Question about the Beseler Universal Color Head

[gorsescent]

Hello. I recently purchased a used Beseler 45MXT enlarger on Ebay. It came to my apartment yesterday, and I spent 2 days to assemble it.

It came with a color head and a digital controller. I have a question about how to change the filter configuration. I'm able to change the numbers for each color such as 40 for yellow, 50 for magenta, and 80 for cyan. However, even when I change the numbers, the color of the light that comes from the color head is always magenta (red). Even when I set the yellow filter and the magenta filter to 0, and the cyan filter to 80, the color of the light coming down from the color head is not cyan but magenta. Since I'm only using the cyan filter, the color of the light coming down from the color head should be cyan (blue).

Is this enlarger broken? Or, am I just not using it properly?

[Drew Wiley]

Cyan is cyan, not blue. Magenta is magenta, not red. RGB are primaries used in additive printing. CMY are subtractive colors used in most colorheads. This is basic color theory. But Beseler did market a couple of additive colorheads at one time, though subtractive heads are far more common. There was a Beseler-Minolta additive head which used small xenon flashtubes. Then there was the Beseler Universal head which employs three pulsed EVW dichroic lamps, with a separate power supply and control panel. Problems with these could be as simple as a burnt-out bulb or so complicated that it would take a very skilled electronics technician to figure them out. Expect zero help from Beseler themselves. Additive printers are much more complicated than ordinary subtractive machines; and this particular version of it was prone to a lot of EMI schizophenia within the triacs etc. They also marketed a version of the head itself intended for only VC black and white printing, which simply removed the blue filter and substituted a colorless piece of glass. IF this is the case in your own particular
instance, you would somehow need to acquire the suitable blue filter for this lamp slot to turn it into a true colorhead. So open the top, look in there, and see
what is actually there - but don't touch anything with bare fingers.

[Drew Wiley]

POSTSCRIPT - Even though this aforementioned colorhead is additive (RGB), the control panel itself is programmed CMY for ease of calculations. There is a feedback circuit allowing this kind of control. Beseler themselves MIGHT still have some of the replacement filters, particularly the blue. If not, you'd have to try
someone custom like Focal Point. But don't attempt a substitution without asking some questions. It's not that simple. Try for the original part first. It should slide
right in.

[gorsescent]

My question was very simple. Is this enlarger broken?

[Tin Can]

My question was very simple. Is this enlarger broken?

Sure sounds like it, but we don't really know what you have. I have 3 Beseler 'color' heads. How about a couple pictures of what you have and why not look inside it and see if the filters are there and if they move in the white light path as they must.

Googling your title brings up this ebay Beseler, http://www.ebay.com/itm/Beseler-Univ...-/331003725998

Which I hope is not what you have...

You mention digital control and digital anything concerning old used enlargers is not a good thing in my estimation. ymmv

[ic-racer]

My question was very simple. Is this enlarger broken?

Is this an additive enlarger? Some of those get blue when the yellow is dialed to the max. and so on..

[Drew Wiley]

My answer was simple. Do what I said or pay someone hundreds of dollars to open up the top and see if all three colored filters there or not. You need to do that
anyway to see if any of the bulbs are burned out. The controller itself will act wacky if any of them aren't working correctly. AFTER that, we can discuss what might
or might not be wrong.

[gorsescent]

Folks,

My problem has been solved!!!

I finally figured out why only the magenta filter worked until yesterday.

The cause was that 2 of 3 light bulbs in the light source (for cyan and yellow respectively) had been unplugged during the shipment from California to Japan. This is why only the magenta filter was turned on until yesterday. I just had to open the black box on top of the enlarger, and connect the unplugged components.

Now, since I properly connected the other 2 light bulbs, all colors of the filters show up.

It's an amazing enlarger. I'm very glad I could obtain this whole system for only $890.

http://www.ebay.com/itm/251988881959...%3AMEBIDX%3AIT

Folks, thank you very much!!!

[gorsescent]

[ATTACH=CONFIG]136206 [/ATTACH][ATTACH=CONFIG]136205

I suppose the current Beseler 45 enlarger has a similar color head. It might be exactly the same.

Mr. Moe,

>Which I hope is not what you have...

What made you think that I purchased a very old enlarger like that?

[Drew Wiley]

Congratulations, both on solving your problem and on bagging a colorhead system worth five times as much as the enlarger chassis itself. If you do buy some spare bulbs to have on hand, I recommend Japanese made USHIO. They'll last way way longer than cheapo bulbs. You can not only do additive color printing with this machine using convenient subtractive controls, but do VC printing either normally through mixed filtration or as separate B or G split printing. For example, set Y to zero, then ratchet C and M to the top setting, and what you get is pure blue - only the blue light will operate. Then ratchet Y and C all the way up, with C set to zero, and you'll get pure green. M and Y together yield red, though you don't need this in black and white printing. This might not sound like correct color theory and it isn't. It is how the keyboard CMY color buttons control what is actually an additive bulb/filter set of RGB light output. But the nature of the design does have some idiosyncrasies (which are hell to solve, so I won't go into them here), the main problem being the risk of EMI (electromagnetic
interference). So I'd keep anything like electronic lighting ballasts or sensitive solid-state gear well away from this machine, or something might become haunted.