Tag: GPU coma corrector

M49 Galaxy

Messier 49 is an elliptical galaxy belonging to the Virgo Cluster of galaxies. Magnitude 8.4 makes this galaxy the brightest in whole Virgo Cluster. Due to its brightness, it’s possible to observe it just by using binoculars. Distance of M49 from Solar system is 52 million light-years.

The picture is a stack of 40 photos with exposure time 5 minutes each. This means more than 3 hours of exposure time.

Technical details

Telescope:Newton 254/1000 mm
Aperture:254 mm
Focal length:1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
Camera:ZWO ASI071MC Pro
Corrector:GPU
Filters:UV IR cut
Exposure:40xRGB 300s
Date:2018-04-11

M95 Galaxy

Messier 95 is a spiral galaxy, which is located in constellation Leo. It is 38 million light-years away from Solar system and it belongs to a group of galaxies with M96 and M105. M95 belongs between the galaxies intensively studied by Hubble Space Telescope, in order to determine Hubble’s constant. Collected results were adjusted with help of satellite Hipparcos and the distance of this galaxy was estimated. The galaxy is drifting away from us by speed 766 km/s.

Technical details

Telescope:Newton 254/1000 mm
Aperture:254 mm
Focal length:1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
Camera:ZWO ASI071MC Pro
Corrector:GPU
Filters:UV IR cut
Exposure:18xRGB 180s
Date:2018-03-29

Moon – Waxing Crescent

After long period of bad weather, I had the opportunity to take the telescope out and enjoy the clear skies. In the early evening, waxing crescent was setting down, so I took the opportunity and pointed my newton on the Moon. The illumination was only 34%, which means that as soon it gets dark, the Moon is not far from horizon and you have to capture it through thick layer of turbulent atmosphere. The picture is a stack of 700 frames.

Technical details

Telescope:Newton 254/1000 mm
Aperture:254 mm
Focal length:1000 mm
MountGemini G53f
Autoguiding-
Camera:ZWO ASI 071
Corrector:GPU coma corrector
Filters:UV IR cut 2"
Exposure:8x1000 frames, best 700 selected
Date:2018-03-21

NGC281 Pacman nebula

NGC281 is a HII region, which reminds a head of the main character in very popular game from nineties. It is located in constellation Cassiopeia and it 9500 light-year far from us. This nebula was discovered long time ago by Edward Emerson Barnard and it is possible to observe this nebula by reasonable sized telescope under dark skies. Well, I wouldn’t see probably anything, because I live in light polluted area, therefore I had to use narrow band filters, which block the light pollution.

The picture is composed out of 66 narrow band exposures, which means slightly more than one hour per channel. First one is bi-color composition of hydrogen and oxygen, the others are in Hubble palette (hydrogen in green, oxygen in blue and sulfur in red).

Technical details

Telescope:Newton 254/1000 mm
Aperture:254 mm
Focal length:1000 mm
MountGemini G53f
AutoguidingTS 60 mm, ZWO 174 MM
Camera:Moravian instruments G2 8300M @-30C
Corrector:GPU coma corrector
Filters:Baader narrow band
Exposure:8x22xHa, 22xOIII, 22xSII 180 s, bin 1x1,
Date:2018-01-13

 


Worldwide coma correction exercise

Introduction

What is coma and why needs to be corrected. Coma is a special type of an optical aberration. It’s mainly visible in the astrophotography – the stars are deformed into comet-like shapes:

Fast Newtonian telescopes suffer from comatic aberration, mainly in the corners of the photos. These telescopes are nowadays very popular between amateur astrophotographers just like me, because they offer the best price/aperture ratio. There is easy way how to suppress the comatic aberration – coma correctors. There are many coma correctors on the market, but there are just a few published reviews or comparisons between them. Therefore I decided to perform the comparison myself. Quite big collection of coma correctors has assembled in my drawer ready to be tested: