Re: [ATM] 32" Focal ratio

["Mel Bartels" <mbartels@bbastrodesigns.com>]

> Aperture is very important, IMHO.  Suppose, for example, you are  hunting
> supernovae where limiting magnitude is almost everything.  The  limiting
> magnitude of an image increases as

Sure, for supernovae, aperture is quite important.  But I'm talking about 
the practical aspects: trying to frame popularized sized amateur objects 
(many of which will overwhelm the chip size on the 32 inch), getting a mount 
to handle it properly, building an observatory, paying for it all: in 
otherwords, the whole practical consideration taken as a whole.  Probably 
I'll echo what was just said, namely, that focal ratio, particularly for 
DSLR's, is maybe the most important.  At f/4 and below, the exposures for 
extended objects are fairly reasonable.

Mel Bartels

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