Giving the scope an idea where it is pointing

Really pleased with SGP and its plate solving which I have set up and now tested over a couple of nights - feels like a big step forward from how I’ve been working until now. It has been working well with the solve and sync function but I notice when you hover the curser over the solve and sync button that isn’t the ‘blind’ one, there is a help window saying the telescope needs to have a rough idea of where it is pointing in order for that function to work. As it has been working ok so far, I presume it has had an idea roughly where it is pointing. But how does it know this? Is it because I always start from the park position pointing towards the pole star and do the first solve and right there? (and always finish at park there). Another question relating to this: if you needed to let it know roughly where it is pointing, where would you enter this information?

One final question please… the Astonometry.net ‘local’ resource is the one that doesn’t require wifi and goes through my Planewave software? I think this is the case but just checking. Thank you in advance.

If the image is coming in from a robotic mount, the mount usually has the ability to share its assumed RA and DEC. SGP would read this through an ASCOM command and set this as the starting point. SGP would also take note of the pixel size and focal length that you had plugged into the equipment control panel too, to know the approximate image scale in arcsec/pixel.

Thank you again for your help and advice Buzz. SGP is connected via ASCOM and EQMOD to my HEQ5 Pro mount. Sorry to be slow on the uptake but how does the mount assume its RA and DEC before feeding that information through? Where does it get that data from? Does it do this by storing the last park position coordinates and assumes they are the starting point for the next session?

Ah, I just made the connection… your tutorials have been a fantastic help to me over the last few days and got me up and running. They are absolutely brilliant.

If the mount knows your location and time, when you point to a part of the sky, it automatically calculates the RA/DEC. This data is available to external apps, through an ASCOM command. It can be slightly wrong, if the polar alignment is off, or the time/location is not quite right too. The centering part of SGP either calculates an offset to correct for errors, or sends a sync to the mount, which updates itself with the information.
One thing to watch out for, if you are using frame and focus tab to take a quick and dirty exposure, the binning has to be the same as the setting in the platesolving tab. I platesolve at 2x2 binning but I have been caught out by F&F being set to 1x1.

Okay - that’s really useful to know. I will make sure the binning corresponds. Thank you.

It is ANSVR: ansvr - Astrometry.net Local Plate solver for Windows

One other thing to be aware of is that most GEMs do not like to be synced when pointing at or very near the pole. You’ll want to slew off from the initial park position before initiating a sync or odd things can happen with your mount.

Jared

Oh really? I didn’t know that and will slew. Thanks for the ANSVR definition also - really helpful and it certainly seems to be working well so far.