Crab Nebula with Lodestar guide cam

[RobertI]

I use my Lodestar guidecam for EAA/Video and get live stacked images during each session which I save for reference. A couple of nights ago I was looking at M1(see report here) and got a nice mono image and a not so good separate colour image of 30 second exposures (unguided). I thought I would have a little go at postprocessing and combined them to produce a single colour image of about 5.5 minutes total exposure. Scope used was an RC6 @ around F4.7.

My processing skills are very limited and the result won't win any awards, but I was pretty pleased that I was able to get the result below from the humble low res mono Lodestar. Might try some more!

[Martin Meredith]

Lovely image for 5 mins. The Lodestar is a real gem isn't it? Could you say more about the processing? Was it LRGB? The brighter filaments certainly look nice and sharp, something I struggle for when combining pure RGB (live) at short exposure lengths.

Martin

[RobertI]

Thanks Martin, I was a bit nervous posting this alongside the fabulous images in this forum! To say a bit more about the process (from memory), I put the colour image into photoshop as a background layer, and overlaid the mono image as a layer on top. I made the top layer 50% transaparent so I could see stars in both layers and then align them both. I then used the 'exposure' adjustment tool to brighten the colour layer to a simalr level to the mono layer (with a resulting increase in noise), and then did a 'luminosity' blend of the two layers, which seemed to bring forth the colour into the mono layer but not so much of the noise. I then flattened both layers and fiddled with noise reduction and de-speckling to make it a bit smoother. I was unable to do anything about the bloated stars. I have no idea whether any of this is 'standard' post processing, but seemed work quite well.

By the way the colour was obtained with 2x30secs for each R,G&B and without the luminance was dim and lacking the detail as you have found.

[Chris]

For five and a half minutes it's really impressive stuff  After enjoying seeing the mono and RGB seperately on your EAA thread, it's also good to see them combined so well into a proper processed Lrgb image. Very impressive for the integration time.

[RobertI]

Thanks Chris, very kind words, it’s been very illuminating and would be great to be able to do this live, but I think there is a limit (unless someone with more Lodestar Live knowledge can illuminate me).