[LargeFormat] 300mm/f:4.5 Xenar mounting question --> Compound shutter sizes

[Richard Knoppow]

----- Original Message ----- 
From: "philip lambert" <philip.lambert@ntlworld.com>
To: <largeformat@f32.net>
Sent: Friday, December 26, 2003 4:00 AM
Subject: Re: [LargeFormat] 300mm/f:4.5 Xenar mounting
question --> Compound shutter sizes


> I don't know if it's true but I heard some parts of the
Compound, maybe the
> iris or the shutter blades, were made of paper.  Seems
unlikely but... PL
> ----- Original Message ----- 
> From: "Ole Tjugen" <oftjugen@online.no>
> To: <largeformat@f32.net>
> Sent: Friday, December 26, 2003 11:18 AM
> Subject: RE: [LargeFormat] 300mm/f:4.5 Xenar mounting
question --> Compound
> shutter sizes
>
  I'm not sure what they are made of. They are definitly not
metal, at least on the larger sizes. Many large shutters
used Ebonite, or hard rubber, for both shutter and diaphragm
blades. The blades in the Compur look like they are made of
this stuff but may be hard fiber coated with something. The
probable reason is low weight. Be very careful cleaning
shutters like the Compound and larger Ilex shutters because
some solvents will attack the material. Also, don't use heat
to force dry them, the shutter and diaphragm blades will
MELT.
  I agree that Compound shutters are about the best of the
large shutters. While the air-brake is a much older
regulating mechanism than the clock-work regulator on Ilex
shutters, which _should_ be more accurate and repeatable, in
fact the Compound is more accurate and repeatable.
  Don't overlook large Wollensak shutters, they are IMHO
considerably superior to Ilex.

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com