Jupiter (08-08-2020)

[rob_r]

My latest efforts in capturing Jupiter from last Saturday night. Perhaps far from the best conditions or planetary position as Jupiter was skirting the rooftops plus there was a brisk breeze but it was clear skies for once in what feels like a month. In any case, I think it is a improvement from my effort from last year which I posted somewhere here. This one just seems a little blurred I guess and I had problems getting a decent alignment on the stacking even after manually deleted some wayward frames. Still got some cloud bands though. Io was touching the disc towards the bottom right. Seems to be about the best size I can get with the current equipment I have so considering a dedicated astro cam, perhaps a ASI224 or 120.

52 lights, at 0.2s at ISO 400
18 darks, at 0.2s at ISO 400
20 bias, at 1/4000s at ISO 400.

Skywatcher SkyMax 127 with Canon 600D unmodded on SW EQ5 GoTo. Removed the diagonal and slotted the camera straight into the back of the scope with a Celestron 2x barlow lens attached.

Pre-processed and stacked in Siril on MacBook Pro. 
Processed and stacked all bias and dark frames, normalised all frames.
Processed and stacked all lights, processed against a stacked bias frame and stacked dark frame, normalised all light frames. Image Pattern Alignment (Planetary - full disk) registration used for stacking, with average stacking with rejection.
Level and curve adjustment in Photoshop with a little hue and saturation tweaks.

I also captured 4 minute videos (roughly 7000 frames at 25fps) for both Jupiter and Saturn but still yet to process these in Autostakkert via Bootcamp. 

[michael.h.f.wilkinson]

Despite the difficulties, I can still make out the GRS. More, shorter subs would certainly help, and generally darks aren't necessary (I rarely take even flats for planetary). An ASI224MC or similar would certainly get more detail, but I think the EOS 600D has a crop video mode, in which it streams the centre part of the CMOS chip uncompressed to video. That can improve matters dramatically.

[rob_r]

3 hours ago, michael.h.f.wilkinson said:

Despite the difficulties, I can still make out the GRS. More, shorter subs would certainly help, and generally darks aren't necessary (I rarely take even flats for planetary). An ASI224MC or similar would certainly get more detail, but I think the EOS 600D has a crop video mode, in which it streams the centre part of the CMOS chip uncompressed to video. That can improve matters dramatically.

Thanks, I'll have a look at that 'crop video' setting. I think the instruction manual refers to it as 'digital zoom' and has 3x - 10x on the 600D. I'll try it next time. I re-stacked it without the additional bias or darks and upped the contrast, seems to have brought out the GRS and banding out a little more. 

Edited August 11, 2020 by rob_r
Added re-stacked image

[Pete Presland]

Some nice detail visible there.