Sharpcap saves WCS data in FITS header

[sve196911]

Hello all,

I use SharpCap for double star astrometry and I use platesolve3 (configured in SharpCap and set-up as default solver) to go to the correct target. In my last session somehow, after plate solving within SharpCap and sync the mount to center to the target, I found the following WCS data all in my FITS headers of all my frames (Image01). They also had the line which says the solution was provided by SharpSolve (image02).

This is however strange... As shown in image03 and image04, SharpSolve is even not set up or configured and I remember the positions were clearly solved by platesolve3 as I saw the popup.

Now for me this is problematic as I need to solve these images separately to have the correct CD matrix for each image. Now the images are populated already with the WCS data of the last platesolve during the imaging session. This seem to be a recent change as before, even using platesolving to position on the correct target, SharpCap did never write WCS data into the fits headers.

So my question.. is this a new behavior ? And most important... how to avoid SharpCap writing WCS or any other astrometric data to the FITS headers ?

[admin]

Hi,

thanks for the feedback - the addition of the WCS data is relatively recent and I wasn't really expecting it to cause problems for anyone, so it is added whenever it is available. I will add an option to turn this on or off for the next update (probably in the 'Saving' page of the settings.

It looks like the PLTSOLVD header always being set to SharpSolve is a bug - SharpCap is using the plate solving engine that you have selected, but the header is written wrongly - another thing I will fix for the next update.

Hope this helps,

Robin

[sve196911]

Thanks Robin,

That would be great if you could manage that.
For my usecase I would need WCS data that are as accurate as possible (up to the one arcsecond) to measure the position angle. So that is why I prefer to solve the actual frames myself and use the platesolving in SharpCap only for sync to target.

Another usecase could be for people who align a stack in AstroimageJ using WCS data. Because they all the same, the alignment is not happening anymore.

I do not want to push you but do you have any idea when the additional functionality would be available ?

Many thanks for your great support!

siegfried

[admin]

Hi,

look out for a new update next Monday - I have made the changes already and I generally do update versions each Monday.

cheers,

Robin