Re: [APML] Petzval hot spot/Binoculars

[Gene Horr <genehorr@texas.net>]

Chris1011@aol.com wrote:

> I guess I will have to spring for costly Zeiss or similar binocs to get full
> illumination of the field (or maybe put up with some light falloff).

Well, the Zeiss may give you full illumination but you aren't going to get
sharpness to the edge of the field.  Although this is somewhat muted by 
their much wider AFOV.  If you limit the comparison to the AFOV of another 
manufacturer the sharpness is the same.

Still, I would avoid the Zeiss for astro use.  For the same amount of money
you can get either a (don't cringe) Takahashi or a Leica, either of which
IMO are better for astro use.  That dropoff of sharpness at the edge of the
field of the Zeiss is IMO a distraction.  For such a cheesy looking exterior
the Taks have d*mn good optics.  But the high power (22X) means that some
sort of mount is required, which IMO defeats the main purpose of binoculars.

Nikon makes a surprisingly good mid-range (~US$600) series that you should
try out.  They don't have the colour correction that the more expensive units
do but sharpness and illumination are very good.  I remember them being 
noticeably better than the cheaper Nikon units, but don't remember
what the reason was.

Gene Horr
genehorr@texas.net

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