P3D Re: Anti-Newton Glass

[fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)]

Just to add a couple of notes to Dennis' informative posting:

>Anti-Newton glass has been used to prevent the formation of the 
>irregularly shaped rainbow hues sometimes seen in glass mounted slides.  
>It is caused by the contact of the film with a glass surface.  It is a 
>very noticeable and objectionable problem.  

I have noticed that Newton's rings form easily in Kodachrome while they do
not form in Fujichrome.  Can someone confirm this observation?

>Whenever the film curves or 
>buckles there is the chance of Newton's rings forming.  

It is important to reverse-roll your film flat, before mounting it. 
Aluminum mounts (like the Albion) offer some anti-Newton protection by
providing a spacing (equal to the thickness of the mount) between the film
and glass.

George Themelis


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