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Problem saving snapshot with ASI294PRO

Posted: Tue Feb 27, 2018 4:05 pm
by LaCasaCorp
Hello,

I had an issue yesterday 3.1.5059.0 taking a snapshot with my ASI294PRO: on screen everything looked ok, but the software saved a non de-bayered version of the image (gray scale with all the fine grid pattern). The software saved the .png files correctly when doing a live stack, later in the same evening.

this it the content of camerasettings:

[ZWO ASI294MC Pro(50416042)]
Debayer Preview=On
Pan=0
Tilt=0
Output Format=PNG files (*.png)
Binning=1
Capture Area=4144x2822
Colour Space=RAW16
High Speed Mode=Off
Turbo USB=48
Flip=None
Frame Rate Limit=Maximum
Gain=350
Exposure=15
Timestamp Frames=Off
White Bal (B)=74
White Bal (R)=52
Brightness=8
Temperature=-4.9
Cooler Power=3
Target Temperature=-5
Cooler=On
Auto Exp Max Gain=285
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=100
Mono Bin=Off
Apply Flat=C:\Users\Federico\Desktop\SharpCap Captures\Flats\90FL - F4 Reducer - ASI294 - Tilt Plate 17_26_35.png
Subtract Dark=C:\Users\Federico\Desktop\SharpCap Captures\darks\ZWO ASI294MC Pro\RAW16@4144x2822\15.0s\gain_350\dark_20_frames_-4.9C_2018-02-16T04_22_41.png
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.467032967032967
#White Point
Display White Point=1
TimeStamp=2018-02-27T01:44:27.1251021Z
SharpCapVersion=3.1.5059.0

Here a little snippet of the saved frame (.PNG)
Snip.JPG
Snip.JPG (125 KiB) Viewed 5562 times

Re: Problem saving snapshot with ASI294PRO

Posted: Tue Feb 27, 2018 4:39 pm
by admin
Hi,

yes, this is by design when you have chosen a 'raw' colour option for the camera. It lets you process the image later with your own choice of debayering algorithm and you get a chance to use better (but slower) ones than the one used in SharpCap. There is a very handy program called 'PIPP' which can do this for you (it's name stands for 'Planetary Imaging Pre-Processor', but it will work for deep sky too).

cheers,

Robin

Re: Problem saving snapshot with ASI294PRO

Posted: Tue Feb 27, 2018 4:45 pm
by turfpit
This might help viewtopic.php?f=35&t=254.

A shameless plug :)

Dave

Re: Problem saving snapshot with ASI294PRO

Posted: Tue Feb 27, 2018 5:58 pm
by LaCasaCorp
something wrong... i tried all four algorithms and the output was always similar to this one (300% magnification)
debayer.JPG
debayer.JPG (42.16 KiB) Viewed 5557 times
the stars were not this colorful yesterday...

Re: Problem saving snapshot with ASI294PRO

Posted: Tue Feb 27, 2018 8:43 pm
by admin
Did you try the debayer on the original PNG or on the JPG snip? JPEG is compressed and will do all sorts of horrible things to RAW images because it basically throws away the fine grid pattern as much as it can...

Can you share a link to the original frame in PNG format (perhaps on dropbox?)

cheers,

Robin

Re: Problem saving snapshot with ASI294PRO

Posted: Wed Feb 28, 2018 1:31 am
by LaCasaCorp
Yes, i did the debayer on the original uncompressed PNG

here is a link to one of the images: http://jmp.sh/09pbIqH

Re: Problem saving snapshot with ASI294PRO

Posted: Wed Feb 28, 2018 8:14 am
by turfpit
  • I downloaded the image from your link.
  • Loaded this into Autostakkert!3 with Color set to autodetect.
  • AS!3 reported BGGR.
I then loaded the downloaded image into PIPP and chose BGGR as the Debayer pattern. I ran the conversion and loaded the output file into Photoshop.
BGGR.PNG
BGGR.PNG (663.55 KiB) Viewed 5539 times
The debayered file is 42MB.

This is a screen snip at 100%. At 300% magnification the image will look 'blocky'.

Dave

Re: Problem saving snapshot with ASI294PRO

Posted: Wed Feb 28, 2018 1:57 pm
by LaCasaCorp
then the debayer or the way the png is saved is not correct... the asi294 has a unique pixel arrangement, could be this the root of the issue?

Re: Problem saving snapshot with ASI294PRO

Posted: Wed Feb 28, 2018 2:38 pm
by turfpit
Federico

You said "the asi294 has a unique pixel arrangement" would that be the Quad Bayer Coding HDR referenced here?

http://www.sony-semicon.co.jp/products_ ... cjk_e.html

Interesting - there seems to be a lot of discussion about this camera on Cloudy Nights.

Soemthing going on here - over to you Robin.

Dave

Re: Problem saving snapshot with ASI294PRO

Posted: Wed Feb 28, 2018 2:49 pm
by LaCasaCorp
yes, exactly, i was just looking at the cloudynights post to reference it here.... you've been quicker than me :-)

https://www.cloudynights.com/topic/5914 ... try8172521