Initial solve and sync set up

Is there a way to do an automated slew and plate solve and sync at the beginning of each mobile imaging session?

Is that something in the current feature set or is it on the roadmap?


What is a ‘mobile’ imaging session ?? as by default you can configure the system to slew\sync at the beginning of each target…

Mobile imaging session - physically setting up at the beginning of each night and then going through 3 or 4 “good” stars to solve and sync to build a pointing model

I may be wrong, but I take it as the pointing model is as per the SkyWatcher handset pointing model ??

As long as your polar alignment is correct, for each session, then it shouldn’t matter about a ‘pointing model’, as the mount will slew\sync to the coordinates provided as part of the target sequence data, and it won’t matter if its a way off on first movement, as subsequent iterations will remove any error as you’ve defined is acceptable.

Technically correct - but I like many never use the hand controller. We use EQMod and then use something over the top to control the slewing of the mount.
The workflow I currently have is (All manual)

Polar Align using Sharpcap and a separate guide scope and cam (Main OTA is too narrow FoV)
Slew to Kaus Australis to focus main OTA
Solve and Sync
Slew to a star west of meridian (Solve and Sync) because PA and actual OTA are always out of alignment by a few minutes
Slew to a star east of meridian (Solve and Sync) to correct the pointing model and be 95% here
By this stage I’m 95% there and happy enough

Slew to my target and start imaging.

It would be good to do the two star align as part of an automated process as part of an SGP script.

I am not using the same mount but, if I level and polar align it carefully, its initial slew is pretty good (within a degree). That also needs the location and time to be correct too.
This mount (a MyT on a tripod) does have home sensor, but on other mounts, like my Avalon or SW, I would set up an accurate park position that accomplished the same.

I then only need SGP to slew and sync and I’m there. Could that approach work for you?

If you are ‘syncing’ with EQMod, then I’d suggest you turn it off, as that can have adverse effects when trying to centre on the target i.e. stored sync point disagreeing with what the plate solve is trying to move the mount to…

But that then begs the question are you actually using plate solving ??

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You don’t want any pointing model in EQMOD, it badly interferes with plate solving with your model ‘fighting’ it.

It’s recommended to delete your model and set the sync option to Dialogue Based.

My process, using your examples, would be;

Polar Align using Sharpcap and a separate guide scope and cam (Main OTA is too narrow FoV)
Slew to Kaus Australis to focus main OTA
Run first target (Slew and Centre scope must be enabled)

The mount will slew, take an image, solve it, adjust the position, take an image, solve it, etc, until the scope is within the number of pixels you specify. I regularly get within 15 pixels in one or two iterations.

It doesn’t matter that your initial slew is off, the only downside is that your first solve will take a bit longer.

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Oh - I wasn’t using the centering feature of SGP - I found it was pretty hit and miss using Dialogue based to get on my target.

I’ll give it a another shot to see if it’s improved since I tried it last

I have been using the slew and center for years. It has always worked - with some care - check the settings to ensure it can plate solve and a mount that can accept movements and actually move by that amount. If your mount has appreciable backlash, it will be trickier. I forgot to change my timebase and it was an hour out in RA. Two slews later, it was within 4 pixels.

Initial solve and Sync works perfectly. I was using it as a pointing model. I’ve changed my approach now