Comet C/2022 E3 (ZTF) @ f/10

[Menno555]

My first real comet capture. Not as spectacular as I hoped it would be though.

It's at f/10 (2032mm), so I only could use short exposure times (4sec) because the comet was just moving too fast.
Also the moon high in the sky and a lot of captures lost due to strong winds, only 80 exposures were good to use. But at least it was mainly clear skies for the first time in 6 weeks.
Talking about the moon: in this FOV the moon just doesn't fit. So it gives a good comparison on how big the comet is in the sky

Bortle 6/7
Meade LX200 8" f/10 ACF OTA
Ioptron CEM25EC mount
Baader IR/UV Cut filter
Zwo ASI071MC Pro camera

Captured with SharpCap Pro @ -10 Celsius / White balance R50 B50
80 x 4sec / Gain 400 / Offset 4
50 x darks, 50 x flats and 50 x darkflats

Stacked with DeepSkyStacker
One stack with comet and starstripes + one stack with stacked stars and blurry comet

Processed with Siril and Photoshop
Siril: Crop, Histogram

Photoshop: StarExterminator used on the stacked stars version and pasted that resulting starfield over the stacked comet at Screen.
Removed the starstripes with the Spot Healing Brush (Content Aware).
Camera Raw Filter (white balance, contrast, darks, color saturation, lightness, sharpening), light noise reduction NoiseXterminator plug-in.

Full res at https://i.imgur.com/np4hNgx.jpg

[timh]

Well done for getting it recorded at all Menno -- nice green colour!

A question for Robin perhaps? Maybe stupid. Can the comet tracking feature in the beta software be applied retrospectively by using 'livestacking ' in Sharpcap on any set of raw frames transferred into the folder camera -- provided of course that the comet didn't move out of frame over the recording period.

I was thinking that given the data you might be able to use the comet tracking feature retrospectively? Of course it also rather depends on the 80 captures that you did get being mostly contiguous withoout too long gaps between them.
Tim

[Menno555]

Thanks Tim!
Over here the tracking feature sadly doesn't work. It does with ROI but not with my mount: it will only accept RA but no DEC. Think there is a fault in my mount but for me not very important since I only use the tracking of the mount

Menno

[Vesmaobs261]

Hi Menno,
Good image with nice round stars, and the dark
background really shows up the dust that the
comet is expelling. Hopefully when the comet is
in my neck of the woods ( southern hemisphere )
the sky conditions will be favourable.
All the best
George

[admin]

Hi folks,

firstly - nice image @Menno

On the subject of the comet stacking feature - yes, you can use it from the folder monitor camera, since it does not rely on having a GOTO mount or anything like that, just being able to detect the bright blob of the comet as distinct from the stars in the image.

If I can work out a way to split the stars out from the rest of the image reliably then I would like to introduce a version of the comet stacking that aligns both the stars and the comet - we'll have to see how that works out.

cheers,

Robin

[timh]

If you were to align the stars as well as the comet then you would have to choose a particular moment in time ? I suppose that you could have any -- whatever looks best -- but start and finish points would be the ideal I think ?

[Jean-Francois]

Hello Tim,

Look here with the comet NEOWISE from 2020: viewtopic.php?p=34182#p34182
I used the "Folder Monitor Camera" and start the Live Stack.

Regards,
Jean-Francois

[Menno555]

Thanks George and Robin!
Here too hoping on some more clear skies. There is a good prediction for next week but (of course ) during the full moon.

Menno

[admin]

Ah, clear skies - loads for a week or two in mid January, not a scrap since

@Timh, yes, you are right - if you stack the two separately then you have flexibility on where to put the comet - somewhere along its track I suppose, although in theory anywhere!

cheers,

Robin

[timh]

@Jean-Francois

Thanks Jean-Francois. That is a good idea and link. Although I missed out on the current comet I also have some frames of the 2020 comet and so I will go back and give it a try.

Tim