Hi,
I have a process flow that I thinks works well enough. However, when processing images taken with a Tri-band filter the results tend to be very red biased.
I know another astro processing app has a "in built" process for handling Trib-band filters. People who use it seem to create a final image that has a more balance colour distribution. I think I have found a way to emulate this process in PI, but I am unsure where in the process flow it should go.
Starting with an integrated OSC image my current process flow is:
- Dynamic Crop
- PCC (broadband)
- Histogram Transformation
- TBVDenoise
- HDR Multiscale Transform
- Starnet++ (produce a "no stars" and a "stars only" images)
- Curves TRansformation (of "no stars" image)
- Morphological Transform (of "stars only" image)
- Pixelmath (to combine "no stars" and "stars only" images - iif((stars only<=0.01),stars only,0.001); ~(~no stars*~stars only)
- SCNR
- Local Histogram Equalisation
Now I think the following PI process emulates the other apps Tri-band specific process:
- Channel Extraction (red to "rHa", green to "gHbetaOiii" + ", blue to "bHbetaOiii"
- PixelMath:
- untick "Use a single RGB/K expression"
- tick "Create new image"
- R/K expression: rHa*1.00 + gHbetaOiii*0.00 + bHbetaOiii*0.00
- G expression: rHa*0.20 + gHbetaOiii*0.80 + bHbetaOiii*0.80
- R expression: rHa*0.15 + gHbetaOiii*0.85 + bHbetaOiii*0.85
So, my questions are:
- Is my standard process OK?
- Does my pixelmath do what I want it to do (see attached image to see what the pixelmath is trying to replicate)?
- Where in my process flow should I add the extra Tri-band steps
I hope that all makes sense.
Any and all comments and suggestion for any improvements gratefully received.
Thanks for any help anyone can give!!
Cheers, Jim
