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Old 27-03-2017, 01:07 PM
glend (Glen)
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glend is offline
 
Join Date: Jun 2013
Posts: 5,184
Thanks Gents, I have been doing some further research on this and found some information from Frank F, the Metaguide author, which outlines how he sets up DEC guiding on his CGE mount. The CGE and CGX use near identical spring loaded worms, so I am going to try Franks recommendations.
He says that RA bearing noise can be transmitted to DEC as wiggles and those need to be corrected. Great bearings minimise this of course. Even with great PA, there maybe a slow up and down movement to DEC on a scale of a 50 second time scale.
Frank recommends setting up a small non-zero value for DEC Reverse in Meatguide Setup, use about 0.3" . The DEC error needs to reach that point in order for DEC corrections to reverse direction. Add abit (200ms) of DEC lash in the Setup page, which is added to whatever amount the mount uses. Offset the balance in N/S direction so the mount is not floating on the gear. Most of the time the mount will not be moving the DEC, but it will be gradually chasing the error in small steps and DEC errors tend to be slower anyway. "A lot of the DEC peaks we see in the guide logs are not actually movements but just unwinding backlash. So it is feasible to see chasing behaviour on the guide plot, and think that you have a DEC problem, when in fact, it is not actual motion."

I need to try this out.
Thanks

Last edited by glend; 27-03-2017 at 01:29 PM.
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