Null data on first frame of data

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pmpmpm
Posts: 3
Joined: Thu Apr 18, 2019 2:44 pm

Null data on first frame of data

#1

Post by pmpmpm »

I have a question about .ser data frame.
Why is the first line of frame data plus one Pixel null?
on the frames I have looked at.
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admin
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Re: Null data on first frame of data

#2

Post by admin »

Hi,

Please can you share the type of camera you are using and the settings that you have used when capturing. Perhaps the best thing to do would be to upload a single short recording (just a couple of frames will do) and the capture settings file saved next to it which will contain all the camera settings.

Cheers, Robin
pmpmpm
Posts: 3
Joined: Thu Apr 18, 2019 2:44 pm

Re: Null data on first frame of data

#3

Post by pmpmpm »

I have had another 'why oh why' moment. This program does not accept .ser extensions but here it is disguised as txt.
The camera is:
p1778_TS-Optics-Astro-CCD-Kamera---Mond ... hluss.html

Peter
Attachments
Red 160x120 08_01_13.CameraSettings.txt
(369 Bytes) Downloaded 107 times
Red 160x120 08_01_13.ser.txt
(168.95 KiB) Downloaded 102 times
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turfpit
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Re: Null data on first frame of data

#4

Post by turfpit »

Peter

Have a read of https://docs.sharpcap.co.uk/3.2/#Configuring%20SharpCap to configure SharpCap.

BTW, the link you gave to the camera you have reports "internal server error".

Dave
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Re: Null data on first frame of data

#5

Post by admin »

Hi Peter,

It looks like you using a camera via a direct show driver, which means that SharpCap is just copying the data that came from the camera directly into the output file with no processing (actually, that's what happens to most types of camera).

I suspect that what is happening is that the developers who wrote the driver for your camera were a bit lazy when writing the algorithm used to convert the Bayer matrix image from the camera into a full RGB image and ignored the problem of trying to perform the calculation on the pixels immediately adjacent to the edges of the image. Trying to work on those pixels complicates the calculation and means that certain speed optimisations can't be used as easily – I have made the same shortcut in the code that SharpCap uses to debayering the raw images from astronomy cameras for display on the screen.

The upshot of this is that the black band round the edge is just how your camera works and I would expect that you would see it in all capture software.

Cheers, Robin
pmpmpm
Posts: 3
Joined: Thu Apr 18, 2019 2:44 pm

Re: Null data on first frame of data

#6

Post by pmpmpm »

I do not know what happened with the link have another try:

https://www.teleskop-express.de/shop/pr ... hluss.html

I thought it was the camera driver.

Does that mean that to get all the data I would like for the scientific purpose of finding aliens I should ignore the first frame or is there a better driver?(best not mention aliens me feels especially as I cannot see any in the data yet).

Where does the first frame begin? is it with the first non zero sub pixel? It would seem so from my analysis of the data frame. This could be an issue with the darkness around a galaxy in our neighbourhood.

Having now read the configuring chapter in the documentation my guess is it may be the "hot pixels" that I am looking for.

Peter.
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