M90 Galaxy

This is my first image of Messier 90. It is not yet as good as I would like it to be. Which is due to bad weather preventing further imaging. As the moon is already too bright, I will have to postpone further imaging at least to the next new-moon phase.
Nevertheless, this image shows already a beautiful spiral galaxy with its companion.

Image data:
Date: 2021-04-15 – 2021-04-16
Location: Graz, Austria
Telescope: 10β€³ 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: 45x120s, Gain 0, Offset 15
R 30x120s, G 25x120s, B 23x120s, Gain 10, Offset 15

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: 10β€³ 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

M104 – The Sombrero Galaxy

M104 is one of the deep sky objects, I could capture during the past week of clear nights. M104 is a rather difficult target for my balcony imaging, as it stays quite low. So the influence of the air movements cauesed by the city, I am looking over, is significantly increasing stars and reducing detail in the galaxy.
Apart from detail level – this 4 hours worth of imaging goes deep enough to clearly show at least 4 small and faint galaxies around M104. The faintest being at 17.9mag.

Image data:
Date: 2021-04-04 – 2021-04-08
Location: Graz, Austria
Telescope: 10β€³ 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: 58x120s, Gain 0, Offset 15
R, G, B: 20x120s, Gain 10, Offset 15

Project: Messier catalog from Bortle 6 home

After several months struggle with my 10 inch Newtonian telescope, I got all configured properly. Camera, Auto-Guider, APT, etc. are well tuned to produce nice and round stars, even in several minutes long exposures.
I am unable to view or image the whole sky from my balcony setup. I may only point to an area within 80 to 220 degrees azimuth (south-east to west-south-west) and an altitude from 12 degrees to at most 70 degrees. In several occasions, this is truly a very limited view, when objects are only visible for short periods. But still, my view is facing south. So over the course of one year, the majority of the well known deep sky objects are passing by. And for the rest of the sky, I will find opportunities to drive an hour to one of my mountain observing spots with Bortle 3-4 skies πŸ™‚
Living on the northern edge of a city with a south-facing view is by far not a good combination for astronomy or astro-photography. Fortunately, the city I live in, is not too large. Therefore, my average night (if the sky is free from clouds), provides a Bortle 5-6 sky (most of the time 19.3 to 19.5 magnitues per square arc second). Visually, I have a hard time enjoying anything apart from the brightest objects. But imaging delivers really pleasing results.
During the last weeks of testing an imaging, I grew the idea to create my own Messier Object images catalog, where almost all images are recorded from this one location, with all its drawbacks. By pursuing this project, I want to show, that astronomy as well as astro-photography are still possible, even though light pollution gives us a hard time…

See the results, as I progress here: My Messier catalog from Bortle 6 suburban home

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: 10β€³ 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

M42 with short 2 second exposures

It is amazing what modern cameras are capable of! Intreagued by learning how to improve the quality of deep sky astro photography, I stumbled upon Dr. Robin Glovers talk and essay on picking the correct exposure settings. Dr. Robin Glover is the creator of SharpCap, which is one of the best recording tools for planetary imaging.
A head full with new wisdom, I tested for myself, how true the statements according image aquisition were. Therefore I selected the core of M42 – around the trapezium – to set all parameters to. Using my 10″ f/5 newtonian telescope, I could set only a mind buggling 2 second exposure length, before saturating the 4 stars. I expected to gain a little bit of nebulosity, as the area around the trapezium is really bright. But what I could gain in post processing the 300 individual exposures is simply fantastic! Compare the 2 images attached – the nearly black one is one of the individual frames used to create the colorful result!

Image data:
Date: 2021-03-25
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:
100x2s R, 100x2s G, 100x2s B

M51 and IC434/NGC2023

Saturday night, the sky was a spectacular sight. I had the chance to go out to one of my favorite places for observing. The sky was so full of stars – it was really a treat! A bit of “discomfort” posed the low temperatures, which were around -10C all night long.

As I arrived later than I hoped for, I immediately set my scope up. Scope and camera setup were up and ready for imaging soon. But then – a series of technical problems began. The scope did not fulfill GoTo commands properly. After solving this, the auto-guider could not calibrate well. I thought, it should be well enough. But upon inspecting the data back home, I had to discard more than 60% of the data due to elongated or totally ruined images. And finally, at around 2am my primary battery gave up (being only discharged 25%) due to the low temperatures. So I called it a night and went home.

The results I could gather are not as i was looking for. This is primarily due to the very low amound of data. But still, I add them here for the records…

Image data:
Date: 2021-03-06
Location: Gaberl, Austria (RGB) + Graz, Austria (H-alpha)
Telescope: 102mm f/7 APO with 0.79x flattener (equals to 564mm focal length)
Camera: QHY183C @ -20C (RGB) + QHY183M @ -30C
Filters: Baader UV-IR-Cut, Baader H-alpha
Guiding: MGEN-II with off-axis guider
Exposures:
IC434: 24x300s H-alpha, 19x60s RGB
M51: 19x60s RGB

NGC 2237 – Rosette Nebula in narrow band

Last night, I captured several subs of the Rosette Nebula (NGC 2237). Most of the subs were in H-alpha. So the O-iii and S-ii data is a bit short in signal. But hopefully, one of the next nights will be clear to add more subs πŸ™‚
The colored image is Ha = red, Oiii = green, Sii = blue. The one in black and white is the pure H-alpha image

Image data:
Date: 2021-03-02
Location: Graz, Austria
Telescope: 102mm f/7 APO with 0.79x flattener (equals to 564mm focal length)
Camera: QHY183C @ -30C
Filters: Baader H-alpha, O-iii, S-ii and IDAS LPS-D2
Guiding: MGEN-II with off-axis guider
Exposures: 20x300s H-alpha, 10x300s O-iii, 5x300s S-ii

NGC 2359 – Thor’s Helmet in narrow band during Full-Moon

Even though the moon was at its brightest, I had to capture some light during the current phase of perfect weather. So I aimed for a rather dim nebula – Thor’s Helmet. I could capture a total of 124x300s images, which I combined to this nice result…

Image data:
Date: 2021-02-27 – 2021-03-01
Location: Graz, Austria
Telescope: 102mm f/7 APO with 0.79x flattener (equals to 564mm focal length)
Camera: QHY183C @ -30C
Filters: Baader H-alpha, O-iii and IDAS LPS-D2
Guiding: MGEN-II with off-axis guider
Exposures: 67x300s H-alpha, 33x300s O-iii

Sunspot 12804 plus prominences and filaments

After a brief break early February, the Sun is still showing activity. Here are the nice but small sun spot 12804 as well as 2 filaments and a detatched prominence.

Image data:
Date: 2021-02-26 13:30 – 14:00 UTC
Location: Graz, Austria
Telescope: 102mm f/7 APO with 4x Tele-Centric
Camera: QHY183C @ -10C
Filters: SolarSpectrum 0.5A @ 60.5C