C/2013 A1 conjunction with 47 Tucanae

[rat156]

Comet C/2013 A1 (Siding Springs) in a close conjunction with the bright globular cluster 47 Tucanae.

Larger version here (http://www.astrobin.com/117084/)

It seems as though this comet is doing a tour of the small Magellanic cloud globular clusters...

Share and Enjoy.

Stuart

[cometcatcher]

Very nice Stuart. I've still got a few hours of processing in front of me but I don't think it will be this good.

[seeker372011]

Great record of the event.

[h0ughy]

holy cosmic dust Batman!!! nice result Stuart, my only pathetic suggestion from an armchair wannabe is to crop out the right hand side and leave the comet and glob - they are brilliant

[batema]

Hi. Beautiful image. Can you tell me how to process that as I have 32 images from last night and am sitting in front of DSS trying to work it out.

[rat156]

HI Mark,

I used CCDStack.

When I acquire the images I use a sequence of two minute L, R, G and B, then repeat. This gives at least a six minute (but typically 8 to 9 minute) gap between like exposures. Then you align as per normal on the stars, sigma reject and combine, which basically eliminates the comet and leaves you with the star field. The same process for all the LRGB subsets and combine these to form the colour image of the star field.

Next you do the same for the comet, i.e. one star align on the comet, the normal sigma rejection will remove most of the star field and leave the comet. In this case there was a lot of 47Tuc still remaining. Then align the R, G, B and L, frames and combine to form the colour image.

Next take the two colour images into photoshop, layer the comet over the star field apply a layer mask and cut out the bit over the comet, then blur the layer mask about 50 pixel Gaussian.

Job done.

I can post the intermediate frames if this helps...

Cheers
Stuart

[PeterEde]

Missed it. Had weekend on KI. Clouds
Great capture