Re: PHD2 Dec tracking goes runaway after Meridian Flip with Mach1
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That is definitely a wrong approach. If the mount runs away in Dec it's because the guide pulses are in the wrong direction and need to be reversed. It's fundamental Of course it will guide ok for a few seconds or even longer as long as no pulses are sent to Dec, but as soon as Dec receives any correction pulses, it will send the mount in the wrong direction and every pulse after that just adds to the error until it goes completely off the guide window. This is fundamental, guys!
From: CurtisC via groups.io <calypte@...>
Sent: Mon, Oct 19, 2020 7:16 pm
Subject: Re: [ap-gto] PHD2 Dec tracking goes runaway after Meridian Flip with Mach1
On Mon, Oct 19, 2020 at 06:12 PM, John Davis wrote:
The mount guides great from starting time until it is time for meridian flip. After the meridian flip, it guides fine for anywhere from a few seconds to a minute - until there is the first commanded correction in Dec. Then the Dec corrections continue and get larger - driving the scope off of the guide star until PHD2 loses it. See attached screen shot from the PHD2 log viewer (post_meridian_flip_guiding_1.pngWhat a coincidence! I don't use PHD2. I use MaxImDL. But I had a recent experience of something very similar. East of the meridian, everything was fine. After the flip, it'd guide fabulously for several cycles, and then suddenly the guiding looked like the guider was chasing a squirrel. I don't have an explanation. But two nights ago it happened, and all I did was put my Mach1 into Park 3, and I remeshed the worm. I had no reason to think the existing mesh was bad, but there wasn't much else I could think to do. The problem disappeared, and guiding on the west side was as good as on the east side.