Crescent Nebula NGC 6888

The Crescent nebula NGC 6888 is a faint, diffuse nebula in the constellation of Cygnus. A beautiful star field of the summer night sky.

This shell of gas (resembling a brain to me) has a Wolf-Rayet star, WR 136, at the center of the nebula which is energizing it with the strong stellar winds. A Wolf-Rayet star is a  massive and very hot star that is expelling their outer layers.

The Crescent Nebula NGC 6888 lies 5000 light-years from Earth. The nebula itself is 25 light-years across. 

This image was taken using a QHY268C cold cmos camera and Optolong L-eXtreme dual narrowband filter for OSC cameras. 

The QHY268C cooled cmos camera

The new QHY268C is a very high resolution and capable camera. It’s 26mp and has small pixels of just 3.76um. This combined with its high sensitivity and low read noise makes for a super camera to image with. 

The Optolong L-eXtreme is their latest and greatest astro filter. It’s designed specifically for one shot colour (OSC) cameras to capture both Ha and OIII emission channels at the same time.

L-extreme Optolong
The Optolong L-eXtreme filter

The Ha functions at 7nm and the OIII at 7nm as well. This differs from its predacesor the L-eNhance filter, which is Ha 10nm and OIII 24nm. This means the L-eXtreme will deliver superior results for capturing Ha and OIII light. Increased detail and contrast with stronger signal. 

Crescent Nebula NGC6888
A widefield image of the Crescent Nebula NGC 6888 taken with the Skywatcher Esprit 100 triplet refractor, QHY268C camera and Optolong L-eXtreme filter.

The telescope used for this image was my Skywatcher Esprit 100 triplet refractor. It operates at a focal length of 550mm and has proven to be an excellent, high quality telescope for astrophotography. With it’s crisp and contrasty capabilities, it has become my primary imaging telescope. I’ve owned and used it now for over three years and have given it a good amount of use. I find the Esprit 100 is a good balance between price, performance and light gathering power. It’s performed well  for me and I highly recommend one if you’re looking for a high quality refractor that is comparable to Takahashi and Vixen astrographs but at a lower cost. 

soap bubble nebula in cygnus
The soap bubble nebula in Cygnus.

A friend of mine, Ron Brecher aka Astrodoc, pointed out that I had also captured the very faint soap bubble nebula within this image of the Crescent Nebula. It’s a very faint bubble of gas thrown off by a dying star thought to be similar to our own Sun. The soap bubble nebula appears almost delicate in structure and is  challenge to capture requiring many hours of data to reveal it. My image is over 11 hours of data and only faintly begins to reveal it. I’ve cropped the larger image to better show the soap bubble nebula.

Technical:

11 hours 20 minutes total

Skywatcher Esprit 100 F5.5 Triplet Refractor http://bit.ly/36w1F7Y

QHY268C cooled cmos camera, 26mp https://bit.ly/37OeYS5

Optolong L-eXtreme filter https://bit.ly/2CkuABq

EQ6 Skywatcher mount https://bit.ly/2C9lap1 

Acquisition: N.I.N.A and PHD2

Processing: Pixinsight

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