Part of the heart

Date of image 14/08/2016

The heart nebula. Processed using DSS. 

Hardware details: Camera: Canon 600D (astro modded). Telescope: SW Evostar 120 with Baader UHC-S filter. Mount: AZ-EQ6 guided using a ST80 synguider. Image details: Lights: 76 x 3min at ISO 800, Darks: 50 x 3min 0 sec at ISO 800 (from dark library), Lights and darks separated by 30 sec intervals. Flats: 50 x 1/40s at ISO 800, Bias: 50 x 1/4000 at ISO 100.

This was quite a difficult target in light polluted skies for a broadband filtered camera. Despite this, I was able to pull out quite a bit of detail. I am glad that I framed the nebula correctly (fitting in the open cluster as well as the vail of gas on the left). Very little of this detail is visible from the individual frames.

A broad sheet of cloud interrupted imaging for about an hour but because of the almost unobstructed view I had of this nebula I was able to get more than 4 hours of exposures. There were no clouds after 00:00. Auto guiding was very stable, as before, the RA axis seems a bit sloppy, often with negative corrections, I checked the tracking rate but it was sidereal. The mount was east-heavy balanced and I reduced the RA aggressiveness of the auto guider around 20%.

Processing was done in DSS, I increased the saturation by 30% and manually aligned the colour channel histograms. The red was stretched considerably more than the green and blue channels to really bring out the H alpha detail. I still have vignetting in the image (this image was cropped), but I do need to redo the flats of distant cloud rather than a monitor screen, perhaps this will solve the issue.