How to create a Synthetic Luminance channel in Pixinsight 

Almost anytime I do a search "How to [fill in the blank] using Pixinsight" I get one of your tutorials as a hit and they are always excellent. This was no exception. Awesome tips. BTW I see you are changing your channel a little bit. All good, still love your content.

Thank you. Why not just use the extract luminance process in PI to extract luminance from RGB? would that also create a synthetic luminance ?

Probably a silly question, but then, this is why I am watching these videos, to learn! Why didn't you do a star alignment when you combined the R, B & G masters to create the SynthL, and then again when you did the LRGB Combination, adding the SynthL to the RGB master? I have several nights of data on M51, so I process each channel for each night and then again align all the sessions before using Image Integration. Is this not necessary? I hope this makes sense!

Thank you, very nice 🙂

Great video Shawn. Two question, would like to see the difference between combing just RGB and SynthLRBG, did you get any luminance on the ends of the galaxy? I just wanted to know how much one gains from creating SynthL. Second would be; what about color images? Is it possible that SynthL has any effect? Thanks.

Great tutorial as always! I shoot with OSC as i dont have filters and a filter wheel, so i was thinking of using this process as follows: 1. Have two master RGB images, one with all the acceptable subs registered (less noise, less focused= and one with the top 20% of the subs (better focus, more noisy) 2. extract luminance from the top20% one, process as usual 3. combine the luminance in the image with all subs registered I did not try it yet, do you think it can work to have the best of both worlds? (less noisy and enhanced focus)

loving your videos, just wondering since I am getting the Optolong L-enhance friday, where you got the Bi Color script?