Quote:
Originally Posted by alpal
Of course that would work but I think
there is a signal to noise advantage in using 3 filters for colour -
in most cases RGB - just like the S/N advantage using narrow band Ha.
Also:
I notice that my RGB stacks have a better FWHM value than the L stack if they are both binned 1x1.
cheers
Allan
|
Thanks Allan :-)
Note that I'm not necessarily advocating hardware binning in the capture of any of these. Binning basically means you're (probably) clipping your highlights to reduce your read noise... consider the Atik 314L+ (my specific one) has read noise in the area of 3.6e, which is about 0.02% of my full well capacity, which is clearly insignificant even when tripled to match the difference in 2x2 binning. I'd rather keep the read noise in and blow out less stars.
As for the SNR improvement of LRGB over LPY, I'd be keen to have that explained a bit more thoroughly because to my way of thinking you'd improve the SNR this way. I just don't see how LRGB can be better than that; you'd have more read/bias/dark noise and less signal because for each R, G, B you're excluding both the others, whereas with PY you're only excluding one component, which directly translates to more signal.
Quote:
Originally Posted by troypiggo
Wouldn't you need a third colour filter to triangulate the colour space coordinate?
|
You already have all three components in the luminance frames. Consider this:
R = 10
G = 20
B = 15
L = 45
vs
L = 45
P = 25
Y = 30
G = L - P = 20
R = L - Y = 10
B = L - (G+R) = 15