Auto center


Still learning to use this fantastic software, really great job guys, I love it !

Not sure if I am doing wrong but when I use the function “solve and sync” just after a slew, SGP does solve and it can use the results for as the reference image target.

But if don’t want to start a sequence, let’s say I want to start a new slew, how doing automatically an autocenter just after the plate solve and sync ?

I did have some issus with j2000/jnow but I found a solution and I don’t know if it’s the same problem here…

Astrotortilla always centered the target after the plate solve (sync scope, reslew to target) so I am a bit confused with the right method.

Also the option “autocenter” is not present here with the latest release :

Does SGP automatically autocenter when the function solve and sync is used as AT normally does ?

Assuming your target has a valid location, you can just right click it and get a whole bunch options (including auto center). This will not start the sequence.

I apologize, but I don’t really understand the rest of your message.

When I used Astrotortilla with my previous software and my dslr (BackyardEOS) for plate solving, my target was always centered in the crosshair, just with one click.

Astrotortilla did the plate solve sync, slew to the target and RE-center, automatically.

Unfortunately I fail do to that with SGP and Ansvr and I don’t understand why.

When I use the function solve and sync with SGP, just after a slew, the target is not centered at all, plate solve is ok, I do get the coordinates, but the target is not in the crosshair.

Ansvr, Stellarium and EQMod, all use J2000.

I would like to get my target in the crosshair when I hit the button sync and solve.

Solve and sync does exactly that…it takes an image, solves it and syncs the mount to that location it does NOT issue a slew to the mount which I think is what you’re expecting it to do?

You want to use Auto Center or Center Here. For auto center you’ll need to setup a target in SGP, right click the target and select “Center On Target”. You’ll need to populate the coordinates of the target, this can be done via the Framing and Mosaic Wizard, solving a previous image, or using a URL from Flickr or Astrobin which has been solved. If the object that you want to center on is in the image you can right click on the image and select “Center Here”. Having said that there is a known issue with Center Here when using ANSVR. So accuracy may vary here.


Thanks Jared !

I just tried to setup a target and the center function works great !! The target is in the crosshair.

But it’s just a shame SGP cannot offer the possibility to re-center (re-slew) the target with the function “solve and sync” like Astrotortilla…

When you start Astrotortilla, it can detect the offset and re-slew automatically after the plate solve so that the target is always perfectly centered with a “one-shot” process…

Another problem here : the function “center here” does not work after capturing a single image with “frame and focus”. Step 1 fails every time and nothing happened…

Any idea ?

Thanks !

Not really sure what this means. Just right click your target and center to your heart’s content. The target’s location is saved so you din’t need to re-enter anything.

Please see this post and we can take a look:

Everything now works great except for the function “center here”, I will give it a try with Elbrus because it fails at step 1.

Regarding my issues with auto centering options, I understand one must setup your imaging session before leaving home, either set manually the coordinates or import an image in the sequence menu for getting the coordinates.

But if you are outdoor and you just want to center a target, without having first populate the target, the function solve and sync will not center the target. It just get the coordinates.

So if your mount is a bit off, there will be an offset between the target coordinates from the sky chart and the coordinates from SGP. And I usually don’t do alignments points, never need it with Astrototrilla,

So I just miss Astrotortilla for this purpose, as it can blindy center a target from the tracking coordinates =

  1. Solve and Sync the scope
  2. Detect the offset
  3. Re-slew to target
  4. Target in the crosshair

One-shot process !

This is what Solve and Sync is designed to do. As previously mentioned it does not slew the scope. It merely synchronizes the RA/Dec that the scope is reporting to where it is actually pointing.

I guess what you’re looking for is something like:

  • Manually slew the scope to a position
  • Solve an image at that location and determine the offset between where the scope thinks it is and where it’s actually at
  • Sync the scope to the correct position
  • Slew the scope to where it thought it was pointing before

So it sounds like you’re looking for a ‘Solve, Sync and Slew’ functionality. We currently don’t have that. I’ll move this to the feature requests.

Really this is only useful when you manually slew the scope and the idea behind SGP is that you should use the automation to do that which will then center it for you. It sounds like you’re doing some manual/automated work flow?

Your best bet at this time is to setup a target in SGP. You can set this up in a lot of different ways.


Thank you Jared for your input !

Yes this is exactly what I meant and I am looking for.

And you’re right, I just have to change my way and think “automated” with SGP. I used to do some manual (slew with Cdc and solve with Astrotortilla).

When I setup a target in SGP, everything now works fine.

I now understand I will first have to setup my imaging session before leaving home and the whole automation process with SGP is just fantastic !

Thank you !