HaRGB compose instructions question
Posted: Wed Aug 18, 2021 6:33 am
So I recently did an HaRGB on the Cocoon nebula, and am actually pretty happy with it right now. 5 hours of RGB, and 3 hours of L'eNhance. I followed the extract/compose instructions which are in multiple places including the manual I believe. But it got me to thinking (always dangerous ).
So first I extracted the R from the filter data and saved that as Ha. Then I loaded the RGB set into R, and the Ha into G, and saved that as my new R. Then I loaded everything up and here's where I have questions. While new R went into R, per the instructions original RGB went into G, B, and L.
I presume that doing this creates a synthetic L out of the entire original RGB? But we are calling that real L for now. But also, with the default composite setting as L+synthetic L (was this wrong?), will it not create yet another synthetic L, this time from (newR, RGB, RGB), and add it to the L, which is synthetic also as noted? I think I need to get out a yellow pad and trace this, but I was wondering if there's a weighting issue here.
Nonetheless, the extra detail added to the nebula was great. It was very, very, very deep red, even after dialing it back, but that was way better than the pink I got when I tried Ha as L.
So first I extracted the R from the filter data and saved that as Ha. Then I loaded the RGB set into R, and the Ha into G, and saved that as my new R. Then I loaded everything up and here's where I have questions. While new R went into R, per the instructions original RGB went into G, B, and L.
I presume that doing this creates a synthetic L out of the entire original RGB? But we are calling that real L for now. But also, with the default composite setting as L+synthetic L (was this wrong?), will it not create yet another synthetic L, this time from (newR, RGB, RGB), and add it to the L, which is synthetic also as noted? I think I need to get out a yellow pad and trace this, but I was wondering if there's a weighting issue here.
Nonetheless, the extra detail added to the nebula was great. It was very, very, very deep red, even after dialing it back, but that was way better than the pink I got when I tried Ha as L.