StarTools

I've been working on the Pacman nebula and have collected a lot of SHO data. I've done what I can in ST, but I always feel like there is something more I could have done to improve the image. I'd like to see what others can do with this data.

Ha 61680 seconds https://www.dropbox.com/s/xcovblqo081n8 ... .fits?dl=0
Oiii 39420 seconds https://www.dropbox.com/s/tbc0qtqeq01ug ... .fits?dl=0
Sii 61800 seconds https://www.dropbox.com/s/3auy2xgxb47s4 ... .fits?dl=0

Thank you for sharing your (very nice!) data. You must have lots of patience to accumulate that much!

I've had a quick play with it, which was good fun, and the result is below. Not sure if it's an improvement or not, but see what you think? I found choosing an appropriate matrix in the colour module was a challenge with all sorts of interesting and unusual results possible. I have also managed to loose some of background nebulosity which your result shows off nicely.

The data was actually collected over two years, both Oct of 2019 and Oct. 2020.
I have trouble getting blue to come through. You seem to have gotten more of it then I did. I think I went with the second SHO mix in the list and bumped the green bias up a bit and also the saturation to around 250%. I think maybe you push the saturation more than I did. As far as the nebulosity, maybe my initial stretch was more aggressive?

I used the [SHO 60SII+40Ha,30SII+30Ha+40OIII,100OIII] and pushed saturation to 360%, Cap green was 49%.

You've got a lot more detail in the 'golden' segments - perhaps if I had dropped the HDR Detail Size Range from 1000, (which I do normally but didn't this time for some reason) more of that nice fine detail would have come out.

Trouble is with all this one can go on tweaking it forever and never be quite sure that we've got the best out of it!

I thought this dso object should be reddish, am I wrong? Maybe these colors are due to the filters used?

mgutierrez wrote: ↑Sun Nov 15, 2020 9:29 pm I thought this dso object should be reddish, am I wrong? Maybe these colors are due to the filters used?

This object has been acquired using narrow band filters. Each filter produces a monochrome image. These individual monchrome channels can be assigned to any colour when combined in post processing, but in this instance the "Hubble Palette" has been used. This usually gives a blue-and-gold appearance, as here, but it's perfectly possible to produce a red and blue (or any other mix). (If you want to see the amazing range of colours that narrow band processing can produce, have a look at the IKI observatory processing competition entries over on Stargazers Lounge https://stargazerslounge.com/forum/294-iki-observatory/. Several StarTools regulars have submitted amazing results, some with complete work flows.

A broad band image would indeed have an overall reddish appearance.

Had a go using st 1.7.45