I have printed several images recently with the lamp retrofit that I designed for the Durst 138S that I have.

Until about three years ago, I printed exclusively with a cold light head and later with the diffusion Saunders 4550 VCCE. (An enlarger that I still own by the way).

Personally, speaking for myself, I thought that I got results more to my tastes when I switched to the Durst enlarger. The problem that arose is that the Thorn lamp for that enlarger is no longer available.

To deal with that problem I located, procured and designed a retrofit using a 1000 watt halogen lamp rather then the 250 watt Thorn lamp. In the design of this I arranged for the enlarger to be used as everything from a point light source to the diffusion of a cold light head. The design process was quite extensive and creating a reflector design was a major problem to overcome.

I have never seen grain so sharply defined as I do when the enlarger is used in the point light source mode. It is really an eye opening experience for me.

I have, as many others have too, I am sure, heard so many things over the years about different light sources. I have found it really interesting and informative to try the different types of light output.

I meant this as a report for those who have questions about the effects of the various sources and having wondered about them or not had availability to determine the differences. No other purpose should be assigned to this post.