Alex Woronow:
It has been very informative to follow the discussions here. It is amazing how difficult a topic  this (RGB versus LRGB) is to understand and how much misunderstanding there is about LRGB. I have continued my years long research into this and have, amazing, just today overturned an important prespective contributed by none other than Juan Canejero, which should set things a little straighter, at least:
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You can read more discussion on page 3, here:
https://pixinsight.com/forum.old/index.php?topic=1636.msg9297;topicseen#msg9297

I agree with these statements 100%, and will avoid L except in the circumstances Juan enumerates.

I think you're again ignoring the elephant in the room which is your use of Topaz AI sharpening/upscaling and denoising. The amount of AI artifacts in your images is just staggering and is more detrimental to your images than anything LRGB can or can't do.
I think the AI processing is very apparent in your image of NGC 1291:
smooth2.jpg
So again that oversharpened pocket shouldn't be there and at the same time those completely smoothed out denoised areas clearly lost so much detail because of overagressive denoising that they just became a blurry mess. The main difference in your comparison between RGB and LRGB was actually these types of artifacts - because the AI reacted to the images differently each time - latching onto a different amount of detail and smoothing out different areas. This however doesn't prove anything except for the fact that AI such as this should not be used in this manner. If you want to truly compare these things you need to do so without any AI upscaling, sharpening and denoising - or at the very least use one dedicated for astrophotography - not Topaz.
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