Enlarger bulbs / condenser v cold light

[dpurdy]

For 30 years now I have printed with an Aristo Variable contrast cold light on my Beseler 45MCRX. That head seems to be giving up the ghost. I also have a regular Aristo cold light as well as my original Beseler condenser head, which has a 6 inch slot for putting in filters above the negative stage.

I have been printing the last week with the condenser and laying 3.5 inch filters on top the film holder. The bulb in this head is a very old 75 watt incandescent bulb. I want to get a new or couple of new bulbs and I wonder if the light technology has changed so that there is a better or best type bulb to buy. I see in B&H there are a few different brands and sizes and brightness and light temperature... as in color. They have a bulb that is 250 watts as well as a 150 watt bulb and the dimmer 75 watt bulb. They also show a heat absorbing glass I could put in.

Can someone advise me on the best way to go? Is there such a thing as an LED made for this normal medium base bulb. I see on B&H that one brand of bulb is smaller, would that have an even lighting problem?

thanks
Dennis

 

[ic-racer]

Yes, change it. The black splotches that incandescent lamps can acquire can cause unevenness in a condenser system. Get some extra bulbs while they are still available. Make sure you get 'enlarger' bulbs that have even frosting. The globe of the lamp is actually projected by the condensers as an image to the negative stage. So irregularities and markings on the lamp can show in your prints. . Stick with 75 watts if that has worked well for you. Only go for a higher wattage if it indicates it is OK in the owners manual. Otherwise you can run in to heat or fire danger.

 

[dpurdy]

Thanks ic-racer. I looked at the enlarger and it states 150 watt bulb max. So I went ahead and bought a few. They are pretty cheap.
Dennis

 

[Doremus Scudder]

IIRC, Aristo will still make replacement tubes for their cold-light heads on a special-order basis. There's contact info on the forum here somewhere if you're interested.

Doremus

 

[Tebbiebear]

IIRC a couple of years a go a few people here did quite a bit of testing and found a common LED bulb that was very well suited for enlarger duties. I will search and try to find the thread.

ETA: I have looked but have been unable to find the thread I was talking about. Perhaps it was a different forum or site completely. If I find it I will post it here.

 

[darkroommike]

The brighter 212 and 213 lamps are rarely needed and put out a great deal of heat. Then you need heat absorbing glass. The common 211 lamp does not heat up so much. There's this for the Omega series of 4x5's, amybe something similar is out there for the Beseler's http://www.modernenlargerlamps.com/Modern_Enlarger_Lamps/Welcome.html

 

[silveror0]

IIRC, Aristo will still make replacement tubes for their cold-light heads on a special-order basis. There's contact info on the forum here somewhere if you're interested.

Doremus

You might try this contact for Aristo replacement tubes:


Louise M. Kessler
Voltarc Technologies/Aristo Lighting Technologies, Inc.
Specialty Products Group
400 Captain Neville Dr
Waterbury, Connecticut 06705
e-mail: Louise.Kessler@voltarc.com
Ph: (there was a url link here which no longer exists)