Focus Assistant

Somewhere to ask questions about the best way to use SharpCap
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lbry9513
Posts: 2
Joined: Sun Sep 09, 2018 10:02 am

Focus Assistant

#1

Post by lbry9513 »

Hi,

Have just started using Sharpcap (3.1 Pro) with a recently purchased ASI294MC Pro camera which I am using on a Sky-Watcher Quattro 8” CF scope.

I am mainly interested in deep sky imaging and am trying to improve focus using the FWHM focus assistant. I am using the FX selection area around a single bright star. I don’t seem to be able to get the shading to appear around the star as indicated in the user manual. I have tried adjusting the black level all the way up to 100% (when the star disappears) and also adjusting the noise reduction but no luck. Also tried adjusting gain and exposure - the preview image looks fine at a gain of 200 and exposure of 1s.

Any ideas on what the problem might be. The focus scores are still appearing and changing when I adjust focus (manual Focuser) albeit it is very sensitive and hard to settle on the best score.

Appreciate anyone’s advice.

Thanks,

Leigh.
lbry9513
Posts: 2
Joined: Sun Sep 09, 2018 10:02 am

Re: Focus Assistant

#2

Post by lbry9513 »

For anyone else who happens to be looking for a solution to this problem, I have found that if you change the colour space to RAW8 or RGB24, the hatching will appear. In RAW16 which I previously had selected, the hatching will not appear.
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turfpit
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Re: Focus Assistant

#3

Post by turfpit »

Well spotted lbry9513.

Robin -I have looked back at the old v2.9 screen dumps on focusing. A lot of the graphics were obtained using either an LN300 style camera or Philips SPC 900 - which was all I had a the time, so YUY2 was used for the Colour Space. The rest were with the Test Cameras, whose Colour Space is cut off on the original images. I will look at this again with the 3.2 manual. I would have thought focusing with the Colour Space to be used for imaging would be best practise - well I do that but I only ever use a Bahtinov Mask for deep sky.

Dave
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admin
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Re: Focus Assistant

#4

Post by admin »

A silly bug - will be fixed in the next SharpCap 3.2 build.

thanks for letting me know!

Robin
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