Re: [APML] Need for a 300 mm "CCD scope"; was: (OT) IC1396 CCD with Schmidt-like FOV

[Gene Horr <genehorr@texas.net>]

> Sean's estimate of $5-6K 300 mm apos would be way outside my comfort zone because
> I already have so much invested in equipment. But I sure would
> be interested in one that sold at $2 to 2.5K

IMO that is doable.  Tak used to sell their 76mm f/4.5 triplet set for around
US$2k.  That gives you 342mm FL and full 35mm coverage (they claimed 6x4.5
coverage, but the corners were pretty bad.)

But keep in mind that focus at f-ratios faster than f/6 starts becoming a 
real b*tch to keep up with.  Camera lens aberrations tend to hide
a lot of the problems that start becoming obvious at these faster speeds.
You have to plan on refocusing when changing filters and between 
exposures.

Gene Horr
genehorr@texas.net

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