Durst CLS 501 - Replaced with Aristo Cold Head Light

Hello! I am in the process of building a personal darkroom - my partner in this endeavor acquired a Durst CLS 501 enlarger from an estate sale. Everything is well maintained - but the previous owner has made several modifications to the machine that I'm attempting to sort through.

The most notable is that the color mixing box seems to have been replaced with an Aristo cold head light. So regardless of adjustments to the color dials the light is cyan. I believe I have the original mixing box in my possession as well, however I am unsure how this should be wired. The cold head light has its own power cables & the other box seems to not be wired - and I'm unable to figure it out based on the manual I found online.

Any advice or pointers on where to look to get started would be helpful.

The light will come from above and pass through your original mixing box. You will need the special power supply and the lamp up above. Do you have the owner's manuals? My 8x10 Durst came with a similar Aristo. I don't use it anymore, but I kept it because the Aristo was made special for my enlarger. Same, it appears, with yours.

If you don't have all the parts to get it working like it originally was, you can still use Ilford contrast filters with the Aristo head. In fact that is how I used mine, until I could get all the parts to get the Dichroic head working.

ic-racer said:

The light will come from above and pass through your original mixing box. You will need the special power supply and the lamp up above. Do you have the owner's manuals? My 8x10 Durst came with a similar Aristo. I don't use it anymore, but I kept it because the Aristo was made special for my enlarger. Same, it appears, with yours.

If you don't have all the parts to get it working like it originally was, you can still use Ilford contrast filters with the Aristo head. In fact that is how I used mine, until I could get all the parts to get the Dichroic head working.

Click to expand...

This is helpful to know! I have a bunch of parts that I wasn't sure how to connect or use - but no manual from the original owner, only the one I found online. Was the light from your aristo also bright cyan? There doesn't seem to be a clear place to put contrast filters - did you just put them under the light box? I'm hopeful that I'll be able to get it running for color prints as well as black and white.

I think there was a time when a popular modification of these enlargers was to fit a Cold Light head. I'm glad I converted mine back to the dichroic head.
This is the under-lens filter holder I made. I used that for a year or so while I got all the parts to get the dichroic head working.