QHY183M flat capture takes forever

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GregL
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Joined: Sun Apr 30, 2017 6:19 pm

QHY183M flat capture takes forever

#1

Post by GregL »

I just switched my camera compliment around and put my 183c on the Z61 refractor and the 183m with the new and just fully populated filter wheel on my VRC6. Ran dark and flat capture for the 183c/Z61 -- seemed reasonable. The darks took forever but not unreasonable as I was using 120sec exposures. Then I switched to do the 183m and went to capture lights for the different filters. Capturing filter 1 (luminance) with 1.5 second exposure (seemed a bit long bit the wizard said it was ok)... never finished. Six frames (1.5sec exposure) in 21 minutes indicated (real wall time was worse). If there a problem? I had frame rate 1 fps, by the way.

greg latiak
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Re: QHY183M flat capture takes forever

#2

Post by admin »

Hi,

If you could post the log file of the attempt to capture the flat frame that failed, that would help.

Cheers, Robin
GregL
Posts: 68
Joined: Sun Apr 30, 2017 6:19 pm

Re: QHY183M flat capture takes forever

#3

Post by GregL »

Thanks, Robin.

Am attaching the logfile from yesterday. Nice and cool this morning so going to take another run at it.

Note - I reran things this morning, this time the whole set of filters generated flats in less than an hour. The 'L' that took forever was really quick. Am running a 'dark' right now with 120 second exposures..

I am curious about a number of things from running the flats wizard -- it pops up the histogram and messages about adjusting the exposure, but nothing registers in this histogram, but there is a white bar at the bottom that typically had values from 53% to 96%.. what is this showing?

Also, the little histogram in the camera tab did consistently show a curve for each -- I left it at linear.

greg
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Log_2019-08-02T15_00_03-3068.log
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Re: QHY183M flat capture takes forever

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Post by admin »

Hi,

Sometimes the histogram can look blank if the vast majority of pixels are either perfectly black or perfectly white – this is because in those cases the histogram would be really tall for either the black or the white level and the rest of the levels would be so small in comparison that you wouldn't see the graph. You can make this less of a problem by making sure that the 'logarithmic' checkbox is ticked in the top right hand corner of the histogram. This makes the vertical scale of the histogram graphs logarithmic instead of linear meaning that you get to see the rest of the graph even if one pixel value has a very high count associated with it.

Cheers, Robin
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