Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart (morrienz)

Celestial hemisphere: Southern · Constellation: Microscopium (Mic) · Contains: Solar system body or event

Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart, morrienz

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Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

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Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

I had a second go at comet C/2021 A1 Leonard last night, and here is a composite image showing my 10:40pm 26th December image (top) compared to my 10:20 pm 30th December image four nights later (bottom). Both the coma around the head and the tail show quite changed structure on the two different nights. some of that perhaps coming from different capture (a stack of 15x 10sec exposures on 26th vs 11 x 30 second exposures on 30th), different stacking, possibly slightly different processing (although I did try and process after stacking similarly, going from memory), and for the 30th Dec capture I avoided direct light from a nearby street light, but I think most of the differences are real. In the 26th Dec image the head was at 14 deg altitude, on the 30th at 18 deg.
Both were taken from near Taupo, New Zealand, with a C11 280mm aperture SCT working at f/2 with a Hyperstar lens, ZWO ASI2600MC Pro colour CMOs camera at -15deg C, no filter (camera has an IR block cover glass), on a 10Micron GM1000 HPS mount. Captured with a ZWO Asiair Pro. No darks or flats. The 30th Dec image was stacked/aligned on the fly by the Asiair's live stacking process, while the 26th image was stacked with Astro Pixel Processor from individual exposures. Processing was with Pixinsight and Photoshop Elements. Most of the detail/structure was made sharp/visible by using Pixinsight's wonderful "HDRMultiscaleTransform" process.

New Zealand Astrophotography
HyperStar Lens Astrophotography
The OSC Club (One Shot Camera)
Comets Imaging
CMOS Imagers
ZWO ASI 2600MC PRO
Southern Hemisphere Astro
Reflecting Telescope Group
ZWO ASIAIR PRO USERS
PixInsight Addicts
Solar System Imaging
Celestron C11 XLT Group
Schmidt-Cassegrain Telescope (SCT) Imagers

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Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

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Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

Composite image. Comet C/2021 A1 Leonard on two different nights, four nights apart

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