Re: counterweight up slews in APPC Pro with Sequence Generator Pro


 

>>>They have not figured out yet that sending the mount via a relative time move, such as is used in every autoguiding program


i am fairly sure most (all?) imaging applications that use platesolving and centering routines do this as well, i don't think it's unique to SGP

goto-platesolve-Sync and repeat until the target is within the centering tolerance



On Wed, Mar 10, 2021 at 7:07 PM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:

I have found that CW up slews within the East limits are slow due to all the safety slews. So for example, if plate solving takes three tries, the mount will go back and forth in and out of East limits three times to move a handful of pixels.
That is because SGP sends a new co-ordinate, a co-ordinate slew, to the mount. It is basically sending the mount to a new position each time, so that always triggers a safety slew when the scope is under the mount. They have not figured out yet that sending the mount via a relative time move, such as is used in every autoguiding program, will move the mount a few pixels without encountering this safety slew issue. A relative move is a timed move at sidereal rate. So moving 15 arc seconds simply sends the mount at 1x sidereal for 1 second.

Rolando


-----Original Message-----
From: Luca Marinelli <photo@...>
To: main@ap-gto.groups.io
Sent: Wed, Mar 10, 2021 8:31 pm
Subject: Re: [ap-gto] counterweight up slews in APPC Pro with Sequence Generator Pro

Duncan,

I have used it and you don't have to do anything special in SGP. APCC has to be setup with East and West meridian limits and the checkbox to allow CW up slews within East limits needs to be checked. Ray can correct me if I am wrong. SGP will just issue a slew command to specific coordinates. APCC realizes that it can access those coordinate in a CW up position within the East limits and it goes there.

Ultimately, I stopped using this feature. While it is appealing in principle, I have found that CW up slews within the East limits are slow due to all the safety slews. So for example, if plate solving takes three tries, the mount will go back and forth in and out of East limits three times to move a handful of pixels. In the end, meridian flips are easy and work well so I find that I waste less imaging time with an automated meridian flip than the overhead of all the CW up safety slews.

Have you set up automated meridian flips in SGP? SGP is able to take full advantage of the declination-dependent meridian limits in APCC.

Luca

--
Roland Christen
Astro-Physics



--
BrianĀ 



Brian Valente

Join main@ap-gto.groups.io to automatically receive all group messages.