Re: [ATM] how good is this mirror?

[Mike Lockwood <melockwo@uiuc.edu>]

John,

john sherman wrote:
> I presume you mean that the bad performance is due to the horrid
> wavefront error, not the f/#. I have observed thru 28" f/3.7
> mirrors which are very well figured, and they give very good images
> on-axis (you would think you're looking thru an f/6). Yes, there is
> coma off-axis, but it is not horrible (it would be horrible if the
> mirror was not figured exceedingly well).

In general, bad mirrors have the same amount of coma as good ones. 
It's the quality of the star images on-axis that are improved with 
better figuring.

> I would really like to know which eyepieces & coma correctors WILL
> handle f/3.7. Anyone know?

A Paracorr + any Panoptic or Nagler I have used seem to work fairly 
well in our 30" F/3.8.

	Mike Lockwood

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