ASTAP FOV command option

[blackdragon]

How do I pass "-fov xx" setting to ASTAP plate solver in Sharpcp.

I put "-fov 0.3" to the "Additional option" in Plate Solving tab, but I got this error right away when I did plate sovle.
"Plate solve failed -something went wrong. Error was: Index was out of range. Must be non-negative and le than the size of the collection (Parameter 'index')
So it seemed that the command line option was not passed to ASTAP correctly.

I tried FOV setting of 0.3 and it was working fine if I used ASTAP standalone, or I did not pass any command option in Sharpcap.

What is the syntax Sharpcap takes for ASTAP command option?

[admin]

Hi,

that looks like a bug in my code. SharpCap will add its own -fov parameter if it knows the field of view (pixel size of camera known and focal length known). The code I had written dealt with that case (remove calculated fov and allow custom one) but didn't cope with the case of no calculated FOV.

I will fix that in today's update, but for now the way to go is to enter your focal length in the plate solving settings (presuming that your camera reports the pixel size, which most do).

cheers,

Robin

[blackdragon]

Is the fix in release 4.1.11388.0?

[admin]

Hi,

yes, the fix is in that new version.

cheers,

Robin

[blackdragon]

Thanks for the quick fix, it is working now.

I am seeing a different issue, not sure if it has been reported.

I usually open a skychart app so I can slew my scope to a target.
I use Sharpcap to do plate solving (in this case, I use USB frame grabbler).

But we I close Sharpcap app, the skychart app complains that the ascom telescop connection is lost. Looks like Sharpcap close the ascom telescope driver completely even though there are other apps are connecting to the scope. Ideally Sharpcap should only close the connection for its communication but leave others untouched.

[admin]

Hi,

yes, at the moment SharpCap will set Connected = false on ASCOM hardware during shutdown. I'm sure changing this would fix your situation, but I worry that it would equally break other people's configurations. You could try using the ASCOM Device hub to connect to the mount and then make SharpCap, Skychart, etc connect to the hub. The hub should deal with connection counting for you and avoid this issue I think.

cheers,

Robin

[blackdragon]

I dont know why fixing it would break others, as ASCOM local server supports it natively.
I would suggest to fix it and leave an option for backward compatibility.