Combining Ha with LRGB

[Notty]

Hello, after a long hiatus from AP I've taken advantage of the last 2 gorgeous UK nights and got some data from the Heart nebula; Ha and LRGB.  Can anyone recommend the best approach of combining the Ha with LRGB? Or should I ditch the Lum and use the Ha as my Lum?  I use (fumble my way around) Star Tools.  Thank you! Andy

[Singlin]

I use Pixinsight to add Ha to the red channel of my rgb image.

[Notty]

I just tried combining the HaRGB so no Lum as I don't know how to incorporate it.  I get lovely detail from my Ha on it's own, but for some reason with the colour it looks awful.  Maybe I need to bin my RGB data would that help? Any ideas? As mentioned, processed in Star tools.  It's not huge data, 3x30 RGB and 30 Ha. Thanks for any advice.

 

EDITED I dopn't know what the orange band at the bottom of the colour pic is, it's a corruption of the jpeg conversion and doesn't show on the TIFF here? Anyway you get the gist from the top 3/4 of the image!

 

 

 

 

 

Edited March 27, 2020 by Notty

[steppenwolf]

I wouldn't really recommend replacing the luminance with Ha as you will likely get very 'pink' results.

Far better would be to blend the Ha in with the Luminance data and red data too as this will give you increased detail and a more balanced output.

[Notty]

17 minutes ago, steppenwolf said:

I wouldn't really recommend replacing the luminance with Ha as you will likely get very 'pink' results.

Far better would be to blend the Ha in with the Luminance data and red data too as this will give you increased detail and a more balanced output.

Ah. So would they (Ha and L) combined during stacking or as an intermediate step in the processing program (ST in my case), as ST only lets me import 4 channels of data, which I expect is normal in all of them?

[steppenwolf]

1 hour ago, Notty said:

Ah. So would they (Ha and L) combined during stacking or as an intermediate step in the processing program (ST in my case), as ST only lets me import 4 channels of data, which I expect is normal in all of them?

To be honest, I was thinking more of combining these in something like The Gimp or PhotoShop - definitely NOT during the stacking process! You should always stack each filtered set in its own group and then combine/blend them in post processing as required. PhotoShop and The Gimp will allow you to import as many layers as you want to combine and blend as you see fit.

[Notty]

I am going to investigate Gimp now I hear it properly handles our types of file. In the meantime I've processed a few times, once with Ha RGB (no Lum) and once by combining Ha and L as a lum. I prefer the first one, but as can be seen compared to the second one, it's completely omitted the large bright white stars visible in the Ha/L RGB combo. I don't know why. Hopefully I can get better results once I've done a bit more research, but I'm quite pleased with this after so long doing nothing - and my first light with ASI1600mm Pro. Thanks for your help.

Edited March 28, 2020 by Notty

[bottletopburly]

old post i know but there is a tutorial here for adding Ha to lrgb using startools if it is of help.

https://forum.startools.org/viewtopic.php?f=4&t=2148