Re: [Leica] Focomat IC question

["Bill" <ohlen@lightspeed.net>]

I have never heard of using cornstarch.

But:

"If the film does not make even contact with the condenser lens, Newton's
Rings may occur....  They are prevented by the metal mask NEWOO (17665) or the
glass disc (17652) slipped onto the condenser.  The metal mask leaves both
surfaces of the film free;  however, this may have the effect that the film
will not be absolutely flat.  The disc (17652) keeps the film perfectly plane
by means of a specially treated surface."
(Kisselbach, 1967, p. 231)

Please remember that this is out of a book and therefore is probably invalid
to folks who only believe what they hear or what is imprinted on their
underwear.

Regards, Bill

Bill Franson writes:


>Hey list,
>
>Mind if I pose a question concerning use of a Focomat IC enlarger? A friend
>needs some advice. He has a real problem with newton rings and has been
>advised to use corn starch?! between the film and the condenser glass that,
>if I understand it correctly, sits directly atop the neg during exposure.
>The fine cornstarch powder apparently creates enough airspace between the
>glass and the neg to eliminate the newton rings but it creates a real
>spotting problem, for obvious reasons. This sounds bizarre to me but I am
>going by what he was told. Is he missing a part? Was this once a
>proceedure? If this is too on-topic for the list to handle please email me
>privately. =;)
>
>Bill Franson
>