Tag: M17

M17 Omega Nebula M18 Open Cluster

Due to moderate focal length of my telescope (660 mm) I managed to capture two Messier’s object in one shot. Specifically it was Omega nebula M17 (on the right) and open cluster M18 (on the left). I already captured Omega nebula some time ago, but due to its very low declination, the picture was not that nice. I was really happy that I got the opportunity on island Milos to capture it again. The cluster M18 is approximately 4200 light-years away from Earth and it has diameter 17 light-years.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length660 mm
MountiOptron CEM25P
AutoguidingQHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM
CameraZWO 071 Pro @-10C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure37x180s, Gain 134, bin 1x1,

M17 – Omega Nebula

Omega Nebula is a giant cloud of the hydrogen gas where new stars are born. It’s around 5000 light years from Solar system and it has 15 light years in diameter. The nebula is located in constellation Sagittarius (The Archer) and it’s the most massive star-forming location in our galaxy. Visual observation is possible, but only with the telescope (medium or big aperture) and from the place with low light pollution.

Since this nebula is visible in summer, there is not enough time to collect enough photons during one night (short nights in summer). Therefore I had to photograph this deep space object several nights (4 in total) and I collected 7.2 hours of the exposure time. Since the light pollution is quite high on the south, I used narrowband filters to collect three channels (H alpha, OIII and SII). I was playing with pixel math and placing partially some narrowband images into Red Green Blue channels and here are the results of my experimentations:

M17-2016-07-05-22Ha32OIII32SII-300s-30C-FL1000-01 M17-2016-07-05-22Ha32OIII32SII-300s-30C-FL1000-RGB M17-2016-07-05-22Ha32OIII32SII-300s-30C-FL1000-SCNR