plate solve and slew

Discussion of using SharpCap for Deep Sky Imaging
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plate solve and slew

Post by glangas » Sun Oct 06, 2019 11:45 pm

I hardly ever use the platesolve and then slew function to get my targets centered, but I decided to give it a try. But I think I'm missing something in the setup. I currently have a separate guide scope and camera. I'll get that up and running with PHD2. I then calibrate the camera and start guiding. But if I want to use the "slew and center" function in Sharpcap, how does the software know what commands to send to the mount after analyzing an image from my main camera? PHD2 hasn't been calibrated to the main camera, just to the guide camera. Is the software smart enough to analyze an image, figure out how it's oriented, and then send a appropriate command to the mount? Does it not somehow use the PHD2 calibration data?

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Re: plate solve and slew

Post by admin » Mon Oct 07, 2019 7:14 pm


This function doesn't rely on the PHD calibration – it passes the image to the plate solving application (Astro tortilla or similar) and gets back the RA and DEC coordinates of the centre of the image. SharpCap also asks the mount where it thinks it is pointing (RA and DEC coordinates). From this information it simple to first tell the mount where it is really pointing from the coordinates extracted from the image and secondly then tell the mount to go back to the position that you have originally set through the hand controller or planetary map which should automatically centre to your target.

Hope this helps, Robin

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