Re: Strain wave gear PEC limitations


Roland Christen
 

One problem with very fast guiding is intermittent loss of guide star due to very short guide exposure. Some places you might get bright enough guide stars for a .5 sec exposure. Other places you might get nothing. When I'm guiding my 130 and 160mm refractors with off-axis guiders and Lodestar guide camera, sometimes I have to use 5 second guide exposures to get a bright enough star to guide on. Things aren't any better with CMOS guide cameras.

Rolando

-----Original Message-----
From: dvjbaja <jpgleasonid@...>
To: main@ap-gto.groups.io
Sent: Sun, Dec 26, 2021 7:06 pm
Subject: Re: [ap-gto] Strain wave gear PEC limitations

40 arc sec peak to peak is outrageous.  And given that, strain wave gears have an erratic PE, if one would call it a PE at all.  Best results with the RST-135 mount is accomplished with very fast tracking with a guide scope and multi-star guiding to compensate for the erratic peak to peak performance.  Cheap products from China are disruptive to the market, but not always the best value for performance. 

Buyer beware







--
Roland Christen
Astro-Physics

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