Hi All,
Well, not really related to the
legendary
arcade game by Taito, but a glorious bubble it is! Actually, I should not avert from the centre showpiece, the magnificent open cluster M52 in all its glory...
So without further ado, I’m pleased to present “
M52 environs”.
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The open cluster M52 appears lost within the rich Milky Way star fields of the constellation Cassiopeia. This cluster consists of approximately 200 stars that are at varying stages of their lives, though most are still in main sequence. The cluster resides 3,000 light years away. To the upper-right of M52, the diffused nebula NGC7635 glows brilliantly. This nebula is commonly known as the Bubble Nebula due to its sphere-like figure. The nebula surrounds a hot star approximately 20 times larger than our Sun, which is visible on the left edge of the bubble. Ultraviolet light from the star causes the gas to glow through a process known as fluorescence. Winds of material are blown from the star which gives the nebula its characteristic outline. The Bubble Nebula is approximately 11,000 light years distant. At the very top of the image is the lesser-known bright emission nebula NGC7538 which is located in the adjacent constellation of Cepheus. This nebula houses the largest known protostar which is approximately 300 times the size of our Solar System! NGC7538 is 9,100 light years away.
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About the image;
I took a minimalist approach to acquiring this image. Total exposure time of only 1.5 hours (R:30mins:G:30mins:B:30mins). I opted to not acquire any luminance data for this image. Instead I used the red channel, thus an RRGB composition. I think the image screams for more data, but appears to hold its own reasonably well. I feel certain greater nebulosity would have been captured with longer exposures or the use of a luminance/Ha filter to bring out some intricate knots of dust/gas etc. Having object pairings in a single FOV adds a pleasant dimension to this wide field image. This is a crop of a much larger frame.
Image processing;
This was one of the simpler processing workflows considering there was no luminance involved, though I did add a few twists to the flow to try new things (experimenting and potentially making things more complex for no apparent reason – such as life). All subs calibrated (dark/flat/bias/hot&dead pixel removal) in MaximDL. Registered in Registar and Sigma Reject combined back in MaximDL. Red channel, pushed through 1 iteration of deconvolution using CCDSharp. I created two RGB balanced images with 1:1:1.1 colour ratios. The first I stretch with DDP (no sharpening). The stretch was rather crude – wasn’t worried about loosing too much data as this was going to be purely used for colour information. The second image was manually stretched (levels/curves) in PS. The second layer (DDP stretched version) was then introduced in PS using a softlight blend, thus providing richer hues/saturation. I used the colour range tool to selectively process the stars and ran the minimum filter. This gave smoother feel to the stars and provided the opportunity to really focus on the individual star colours – rather important for wide field aesthetics. I made adjustments to saturation and normalised the selection. Red channel added as luminance and stretched manually. Minor noise reduction performed, though think I could have been a little harder in the dim areas. Flattened image before finalising.
Thanks for looking, hope you enjoy it.
Cheers