[Leica] Solutions for avoiding newton rings on the foco mat

["FB" <frederik.boone@harol.be>]

Thanks a lot for your help in solving my newton-ring problem.
First of all I was wondring why Leitz made enlarges which were Newton 
sensitive. The answer is that they were not newton-sensitive with the 
emulsions of the 50's and 60's. They were not that thin and glossy.
The solutions can be divided in two groups :
1. Anti-newton glass
- - Leitz anti-newton glass but the Leitz anti-newton glass is hard to 
find (impossible ?)
- - Make anti-newton glass yourself with the AN-glass of a 6x6 slide 
frame. That must be a good solution but glass doesn't cut as easily as 
paper and make sure the edges do not scratch the negative.
2. Avoiding contact between the negative and the condensor.
- - Tape of the 24x36mm frame and make sure the tape is not too thin 
(the misake I made).
- - Make a frame to put on the negative stage with a 24x36mm cut out. I 
made it out of medical film.
I am working with the last solution now which works very well for me. 
I also have the feeling that it is more forginving for dust on the 
negatives.
Greetings,