Re: How much dec drift, field rot, and periodic error allowable?

Chris L Peterson wrote:
> On 29 Jan 2006 17:01:22 -0800, "canopus56" <canopus56@xxxxxxxxx> wrote:
<snip>
Chris wrote:
> My rule is simple: if I can measure it, it's too much. These effects
> alter the PSF: they make it broader and possibly asymmetric. I evaluate
> my PSF by taking several short exposures (no more than a few seconds)
> and measuring the FWHM and elongation.

Thanks. I'll stick with my "minimize/record alignment/tracking"
strategy.

<snip>
> Wind is by far the most significant contributor to a broadened PSF with my setup. <snip>

Ditto here. - Canopus56

.

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