Astrophotography: The Swan Nebula

Having visited dark skies and saw the summer milky way for the first time in my life some two months ago, I went on and lugged my imaging setup across the border into dark skies northwards into peninsular Malaysia. Far from the blazing city lights of Singapore, I found myself lucky to have a perfectly clear night, a rare occurrence under tropical skies. Testing out my new imaging rig - an iOptron ZEQ25GT mount with my trusty 800mm f/4 Astrograph, I turned my telescope towards Sagittarius, where deep sky jewels abound. Having taken some time to drift align and get my autoguider up and functioning, I managed only one object from the region, and that is the emission nebula M17, also known as the Swan or Omega Nebula.

With a total exposure of 40 minutes using an unmodified DSLR, I was able to pull out a reasonable amount of detail.

Being primarily a hydrogen alpha emitting nebula, the unmodified DSLR used only allowed approximately a quarter of the HA Data through its IR filters. As a result, I have lost a significant amount of red nebulosity in the periphery. Still, imaging from dark skies, a hint of the surrounding ionised hydrogen gas can still be seen.

Photographic Information:

Imaging location: Mersing, Johor, Peninsular Malaysia (Light pollution: Suburban region)

Date of data acquisition: 27 July 2014

Exposure Details: 13x3min, 800mm FL at f/4

Camera: Canon EOS 600D Unmodified

Stacked with DSS, adjustment of curves and colors in Adobe Photoshop CS6.