Compatability of Aristo cold lights across Beseler 23c and 45 MXT, and questions

[Cliffordk33]

Couple of questions for this forum and looking forward to joining again and being part of the community.

In my Beseler 45 MXT, I have an Aristo Cold light head, D2 HI, I believe the bulb would be a V45. Years ago I built a darkroom and made 4 beautiful prints before I had to move… this was back in 2007, the Great Recession. Anyway, have rebuilt a new darkroom in another state.

I have the Beseler Timer, and I have a chance to get another new timer, with transformer and contractor (?)

1) I believe these came with a Beseler 23C, are the transformer and contractor compatible across Aristo lights or do are they bulb dependent? I did not use any of these before and made great prints. What does the contractor do?

2) I also have a CB-7 condenser enlarger. With an adapter, would the Beseler 23C Aristo cold light be compatible with either of these enlargers, the MXT and CB-7? I will only be printing an MF 6x6 negatives. And then lastly, would any heads, cold light be compatible on the CB-7 and 45MXT? I understand that a lot of the configurations and compatabilty of lights/condensor is about going up to a 6x7 or 4x5 ince negative, but as mentioned I will only be printing medium format 6cmx6cm.

Thanks in advance for the input.
Clifford

[Alan9940]

Are you sure the bulb in your D2 HI is a V54? What color is the light? If not a greenish color, then it's not a V54. Regarding timer capability, it's not bulb dependent with cold light heads. I don't know the technical details, but there is something unique about a cold light switching on/off that causes issues with timers. No experience with the CB-7 so can't help there.

[Cliffordk33]

Thanks for input, believe the light is pretty 'white', not greenish. I didn't think the timer was bulb dependent but what about the transformer and contractor, or the head itself? As it is called, do you know what the contractor does and if that is bulb or head dependent?

[Chuck Pere]

Here's a link to Aristo info that may help you: https://www.light-sources.com/soluti...risto-archive/

If the transformer you are talking about is for the 23C Aristo lamp it is only used for that lamp. The 23C has a separate transformer and the D2 has the transformer built into the head. Basically you could put any head on any enlarger if you make an adapter. One problem is that the cold light is sized to be installed right on top of the negative carrier. If you space it off the carrier it might not cover your negative corners. I got the factory adapter for my 23C to let me use 45 heads. I can't recall the part number right now. So I put a D2 on my 23C spaced higher so I could put in a filter drawer. The larger cold light still covers 6x9. You are probably better off just printing the medium format on the 4x5 enlarger.

[Luis-F-S]

With any cold light head, IMHO you really should use either a Metrolux timer or a Zone VI Stabilizer. Otherwise, the exposures will drift and not be the same. I prefer the Metrolux because it controls the "length" of the seconds thus providing consistent light output, whereas the Stabilizer essentially backs down the light intensity, and then increases it and decreases the intensity to stabilize the light. Both work, but I prefer the way that the Metrolux does it. The Metrolux II is still available, there were some for sale on this forum a while back. I would not buy a new timer unless it were a Metrolux. A contactor is typically only needed if your light wattage exceeds the timer rating, I believe the Metrolux is rated for 750 W making a contactor unnecessary. Most of the better timers are rated at least for 500 W, again way more than a cold light head wattage.

Either the W54 or the W45 Aristo bulbs can be made to work with the current VC papers and the Beseler. If I remember correctly, for the W45 head, you would use a CC40 filter in addition to the paper grade filter. I don't believe the CC filter is required for the W54 bulb. The main difference with the heads AFAIK is the diameter of the Aristo housing size for the different enlargers. If you need more info, you are welcome to PM me. L

[Kevin Crisp]

I tried to get two older Aristo heads to work with modern VC paper of three different brands, using every filtering trick I could find on-line. I never got satisfactory results -- or even close. Switched to the V54 (bright aquamarine color) and everything worked great. I know people give this advice about fixing the issue with filtration, but I certainly couldn't get it to work. I was highly motivated too, for the cost savings.