Leo Triplet – MatP's view of the world

2021-04-122021-04-12

NGC 3628 – Galaxy in Leo Triplet

This is the third and dimmest galaxy of the Leo Triplet. The other two galaxies M65 and M66 are quite close, but did not fit in the image. They seem to be not only close in our view. The three galaxies might interact in gravitational forces.

The dust band in front of the edge on view of the galaxy render it a very interesting and beautiful deep sky target.

Image data:
Date: 2021-04-04 – 2021-04-08
Location: Graz, Austria
Telescope: 10″ f/5 Newtonian with GPU corrector (1250mm focal length)
Camera: QHY183M @ -20C
Filters: Optolong RGB + Baader UV-IR-Cut
Guiding: MGEN-II with off-axis guider
Exposures:
UV-IR-Cut: 60x120s, Gain 0, Offset 15
R, G, B: 30x120s, Gain 10, Offset 15

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2021-04-02

M48 and M65+M66 – finally with round stars

The past months I had trouble with my 10 inch scope. I was not able to image with nice round stars. So i kept imaging with my smaller refractor, as stars were rendered round. After some investigation and chat with fellow astronomy club members, I could nail down the cause of the elongated and triangular stars: the auto-guider as well as a too short settle time after dithering were messing up. So, to achieve the round stars everyone is after, I had to increase the settle time after dithering (otherwise, I got double-images due to the offset) as well as the guiding parameters in MGEN. My settings for off-axis guiding on 1250mm focal length are: Threshold: 0.1, Aggressivness: 100% in RA and 80% in DEC and 2×2 binning.

The first test target was M48 with 50% aggressiveness. Stars were not yet fine. The second target was M65 together with M66. Stars are fine!

Image data:
Date: 2021-03-31
Location: Graz, Austria
Telescope: 10″ f/5 Newtonian with GPU corrector (1250mm focal length)
Camera: QHY183M @ -20C
Filters: Optolong RGB
Guiding: MGEN-II with off-axis guider
Exposures:
M48: 83x10s L, 46x20s R, 30x20s G, 30x20s B
M65+M66: 48x60s L, 39x60s R, 32x60s G, 20x60s B

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2021-02-162021-02-17

Leo Triplet with H-alpha and O-iii enhanced

During the last few days there were really promising clear nights. I recorded several data sets from my urban location (under these conditions, going up the mountains would have been a treat!). Now, as there are clouds again, I am processing the captured data. Here is the first result from the Leo Triplet (M65, M66 and NGC 3628).
I still have not yet received my color filters. So here I have a combination of luminance (UV-IR-Cut), H-alpha and O-iii data.

Image data:
Date: 2021-02-12 – 2021-02-14
Location: Graz, Austria
Telescope: 102mm f/7 APO with 0.79x flattener (equals to 564mm focal length)
Camera: QHY183M @ -30C
Filters: Baader UV-IR Cut + IDAS LPS-D2, narrow band Ha, Oiii
Guiding: MGEN-II with off-axis guider
Exposures: 41x100s Luminance, 20x300s O-iii (2x binning), 30x300s H-alpha (2x binning)
Sky-Quality: 19.4-19.6 mpss

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