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Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Mon Nov 02, 2020 6:29 pm
by ryanha
I just got the new ASI294mm mono camera and ran the sensor test.

The gain/eADU numbers look way off. If I divide by 64, they look right. (camera is 14-bit so divide by 2^6 if it thinks it is 8-bit?)

I saw an earlier thread about ASI drivers reporting the wrong bit-depth and I could not find a place to change it manually so I assume this is a bug?

lmk if there is other detail/info you need (or if this is actually operator error).

FWIW, here is the output from the test:

https://docs.google.com/spreadsheets/d/ ... sp=sharing

--Ryan

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Mon Nov 02, 2020 7:56 pm
by admin
Hi Ryan,

my first guess is that you ran the analysis with the camera set to 8 bit mode (MONO8 in the colour space option). Hopefully if you change this option to MONO14/MONO16 (not quite sure which it is for that model) then you should get the correct results.

https://docs.sharpcap.co.uk/3.2/#!2!Cap ... and%20Area

Cheers, Robin

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Mon Nov 02, 2020 9:09 pm
by ryanha
Lol, someone else just pointed that out to me.

I must have been sleepy as I did not see that setting.

I'll give that a shot tonight. Thanks!

--Ryan

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Mon Nov 02, 2020 9:50 pm
by donboy
For what it's worth I got this for Mono16:
ZWO ASI294MM Pro.txt
(1.68 KiB) Downloaded 99 times
Don

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Mon Nov 02, 2020 11:52 pm
by ryanha
@donboy, what do you use as your offset?

--Ryan

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Tue Nov 03, 2020 5:13 am
by donboy
I believe SC set it to 8 for the analysis. I normally don't use an offset with my cameras. I believe that the ascom driver sets offset to 30.

Re: Sensor test reporting 8-bit on ASI294mm (mono)

Posted: Tue Nov 03, 2020 7:35 pm
by admin
Hi Ryan,

those figures look reasonable – I wouldn't expect them to be very different from the values that get produced for the colour version of this sensor.

SharpCap will adjust the offset/brightness/black level controls during the analysis process to ensure that the values are high enough to separate the histogram peak from zero point when taking measurements.

Cheers, Robin