light for enlarger

[dileep prakash]

HI.

I want to make my own black & white enlarger for 4x5 negs. What is a good source of light for a diffuser type enlarger. Is the Mercury-Argon grid (suggested by Ansel Adams)a good light source for todays enlarging papers (black & white.

Comments and suggestion please.

thanks Dileep

[Michael S. Briggs]

For all papers you need blue lot as part of the spectrum of the light bulb. If you want to use variable constrast paper, then you also need green light. For color, you need all three primiaries. Why not check with the manufacturer of the bulb you are considering? Or buy a cold-light head (e.g., from Aristo) and build your enlarger around it. These cold-light heads are probably close to what Ansel Adams was mentioning.

With the price of used 4x5 enlargers, I don't see the point of making one. You might consider buying a used enlarger and adapting the features that you don't like.