C/2021 A1 Leonard, 21st December 2021

[Pilgrim]

Today's (21 December 2021) Leonard Comet.
Image was taken in the twilight when comet was 25°-12° above the horizon.

73 x 30 sec (LRLGLB sequence, 37x Light, 12x R G and B at gain 100)
Guided by comet's core, no dithering (key point for processing used).

Post-processing pipeline is the same as for yesterday's image (https://www.astrobin.com/7tq6rf/)https://www.iceinspace.com.au/forum/showthread.php?t=195813:

1) Weighted sum with strong sigma clipping to make comet-only image.
2) Subtract (1) from each raw frame getting stars only image with comet subtraction error artifacts
3) Aligning (2) by stars
4) Stack (3) with strong sigma clipping getting rid of residual comet core artifacts.
4.a) Some manual magic to cleanup the rest of artifacts
5) Combine (1) and (4) via simple addition.


Hardware & Software is the same too:
Tal-250K with F/6 reducer MkII, ASI2600MM camera with ZWO filters, EQ6PRO mount. Balcony in Brisbane.

Software: APT, PHD2, Iris, FITStacker, Photoshop


Bigger version on AstroBin (https://www.astrobin.com/j85eoz/)

[rustigsmed]

nice and smooth Igor - nice outer detail too.

[Hans Tucker]

Wow ... nice capture :thumbsup:

[multiweb]

Another corker Igor. :thumbsup: You can see the tail getting elongated with some details now. You should do a time lapse.

[JA]

A wonderful image Igor :thumbsup:

Best
JA

[Dave882]

Wow really nice shot. Super smooth and clear!

[Mick]

:thumbsup: nice one

[Aussie_Dave]

Very well captured, processed and edited Igor, love the detail.

[TerryC]

Even better than the first one Igor

[gregbradley]

Stunning. Great work.

Greg.

[Prickly]

Hi Igor

That’s a very clever approach to getting the image without trailing of the stars. It has worked a treat. Really nice picture.

Merry Christmas!
David

[Camelopardalis]

Great shot Igor, well done :thumbsup: