Friday, February 23rd, 2018

Galaxies Messier 81 and 82

image 5

There is a story behind this image. A few weeks ago the CEO of LightBuckets, the remote telescope outfit, made available for free a mountain-load of data for his customers to process and post their results on the LB Forum. A half-dozen of us said we would love to have a go at it. Everyone but me (it seems) swallowed the whole load of data and produced some beautiful pictures. I could see I was not at their level of expertise. What to do?

Well, I decided to pick a much smaller subset of the data mountain, only 8 measly Luminance frames and an even measlier 5 each of Red, Green, and Blue. I figured that would allow me to do fair justice to the two galaxies, but I would not be able to dig deep into the space surrounding them to show very distant stars and wee-looking galaxies or cosmic dust. The image above was my best effort and it was duly posted on the LB Forum along with the work of the Masters. So far they haven’t taken away my password. Anyway, enjoy it as just another pretty sky-view.

The way this works, in the unlikely event that you are interested, is when you break up the total telescope camera exposure for the Luminance (brightness) image, for instance, into 8 shorter exposures it allows them to be stacked and averaged automagically to produce a single Luminance image with less background noise. If you dare ask why, I’ll simply refer you to a book that I don’t fully understand.

Dave, wannabe astro-artist.