Re: [APML] Tak FSQ-106

[Chris1011@aol.com]

In a message dated 5/2/2002 7:05:36 PM Central Daylight Time, robgendler@worldnet.att.net writes:


> There are others with more experience on the list who can
> comment
> on the petzval design. The overall design, light weight, fast F-ratio (F5),
> and sharp optics


A Petzval of this size will always vignet when used with 6x7 format, but some of this can be taken care of in image processing. Tony Hallas has done some work on negs taken with this scope so he can tell you more about the extent of vignetting and how he has been able to compensate for it.

In a typical Petzval lens, the size of the unvignetted field will be approximately 1/2 the size of the secondary lens set. The point where the light falls off to zero will be approximately equal to the outer diameter of the secondary lens set.

Roland Christen