A couple of days ago, I went to work in Abrau-Durso, took with him a mini-astrograph. The main task was to shoot the nebulae in Scorpio, but I could not resist and decided to shoot my favorite nebulae in Sagittarius – M 8 and M 20. Local light pollution interfered noticeably, but closer to one in the morning some of the lanterns were turned off. The sky was noticeably better than Supsekh, but the filter Optolong L-Pro is still useful and now it will be in the camera all the time. With the white balance did not arise.
M 8

M 8 “Lagoon” and M 20 “Trifid” nebulae, June 9, 2019.

-Samyang 135\2.0 ED Canon EF lens
-filter Optolong L-Pro
-Canon 550Da
-mount Sky-Watcher Adventurer
23 frames per 60 s, ISO 1600.
Processing: calibration and stacking withDeepSkyStacker, post-processing with Fitswork, noise reduction with PixInsight LE.
At scale 100% — at link.
Location: Russia, Abrau-Durso.

Interestingly, almost a year ago I shot the same area, but without a filter and with a lower ISO (400).

I recently purchased a 12 nm oxygen OIII CCD filter, so now I can fully do bicolor (h-alpha + OIII) shooting. The first object for such capturing was Eskimo, a bright planetary nebula in Gemini.

Туманность NGC 2392

The Eskimo Nebula NGC 2392. April 3, 2019.

-telescope Meade LX85 8″ f/5
-Baader MPCC
-filter Optolong H-alpha 12 nm (358 х 5с)
-filter OIII CCD 12 nm (588 х 2 с)
-camera QHY5III178m
Software: PIPP (calibration), Autostakkert (stacking).
Location: Russia, Anapa, backyard.
Scale 50%.
Full size – link.

Туманность NGC 2392

Cropped image

I managed to shoot the Seagull nebula in the constellation Monoceros 5 times. Literally before the shooting, the weather deteriorated and the whole sky was overcast with clouds. Several trips out of town were wasted because of the clouds. On February 5, 2019, the weather still took pity on me and was able to fully capture this interesting area of ​​ionized hydrogen. Below and to the left of it is the Thor’s Helmet nebula in the constellation Canis Major, which got its name for its resemblance to the winged helmet of the Scandinavian thunder god. The departure was very successful, there were only a few clouds at the very beginning, while I set up the autoguider and searched for the nebula. There was wind, but the rocks were well protected from the it.


The Seagull and Thor’s Helmet nebulas, February 5, 2019

-Samyang 135\2.0 ED Canon EF lens
-camera Canon 550Da
-filter Svbony CLS clip EOS-C
-mount Sky-Watcher Adventurer
-autoguider: finderscope Sky-Watcher 50 mm + camera ZWO 290 MC.
35 frames per 120 s, ISO 1600.
Calibration with PIPP, stacking with Fitswork.
Scale 25%. Link — at scale 100%.
Location: village Supsekh, Kuban, Russian Federation.

There were great difficulties due to red halos – the result of using a CLS filter with a modified Canon 550Da camera. When shooting without a CLS filter, they practically do not interfere, but due to the noticeable light pollution, I still had to use this accessory. The filter does not transmit light between the red and green ranges of the spectrum, which leads to a choice in focusing – either in the red channel or in the green. It is possible that using a more advanced L-Pro type filter will improve the situation. A compromise is possible – focusing between the red and green channels, but this will lead to a decrease in resolution. Perhaps next time I will try this kind of focus. The problem itself lies in the photo-lens – undematured chromatism and spherical aberration in the red channel.
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