SNR 1987A with ASI290

[John Hothersall]

SPX350 F9.1, ASI290, Baader LRGB Astronomik UHC. 0.38"/pixel

My new planetary camera a back illuminated uncooled USB3 CMOS ZWO ASI290 mono is very sensitive and perfect for bright deep space objects like planetary nebs. Full resol'n 2036 x1096 pixels at 2.9microns but binningx2 gives 5.8 microns.

You can image in 8 or 16bit (actually 12bit) but binning is strange as with 8bit it increases brightness/noise as usual but in 16bit the bin is average which opens up the dark layers and reduces noise dramatically (16bit is actually 14bit when binned). Cmos binning is different but the maths shows a big advantage to average binning.

I always wanted a go at the SNR 1987A, after moving house in 2017 I can now see the south easily with my new setup.

The remnant seemed brighter than I imagined at 16th mag rather than 18th I had expected. The night was breezy so the 3 sec subs were damaged so I took many and just picked out the undamaged ones with UHC/RGB which took a long time. 1987A stands out as a red oval.

UHC-194x3sec
Red-58x3sec
Green-48x3sec
Blue-109x3sec

I have a HST of the SNR in detail and a GIF to compare my image with HST wide field.

The ASI290 binned is a shade better than Lodestarx2 in sensitivity but with smaller pixels and more detail - would work as a guider too.

Regards, John.

[multiweb (Marc)]

Cool project and very well executed. A needle in a haystack.

[Merlin66 (Ken)]

Whoooo
Well done!
Great catch.
I'm very surprised to hear your experience with binning of CMOS cameras
(You're correct the ZWO page shows the IMX 290 can(?) run at 2 x 2 binning.)
Very interesting......

[Atmos (Colin)]

Yours is a little better resolved that my attempt a few months back. I was hoping someone else may be able to get more detail than I did but it doesn’t seem like it’s possible without your own personal HST.

[John Hothersall]

Thanks for the interest, not a pretty image but I always wanted a go at this challenge.

Ken, the CMOS binning is different, the ZWO forum members had a complaint about average binning for the 290 but the technical guy would not add the bin for 16 bit saying there was no advantage. I was skeptical but after looking at the maths it seemed to be true and after testing I am very pleased with the noise and sensitivity. Can't wait for the planets.

https://forums.sharpcap.co.uk/viewtopic.php?f=35&t=262

Regards, John.

[RickS (Rick)]

Nice catch, John.

[cometcatcher (Kevin)]

That's pretty cool actually.