|
Hi Russell,
The core is already looking very good.
Your excellent back to back comparison of the H-alpha RGB and straight RGB provides a superb tutorial example of why using H-alpha as a luminance channel doesn't always work. The OIII is not co-located with the H-alpha. The G and B channels from the RGB already pick up some of the outer OIII ring, but the use of H-alpha as luminance actually blocks almost all of that.
If the photographer is interested in is the nebula, rather than the stars, the best thing to do is to just use H-alpha and OIII, and not bother with RGB at all.
There are many other examples where the H-alpha and OIII are almost totally separated in space, especially in nebulae in the greater and lesser magellanic clouds, and there is consequently no place for H-alpha as a luminance channel. Same applies (to a lesser extent) to other WR nebulae such as Thor's Helmet, and to many SNR's and planetary nebulae. All these objects are best photographed in H-alpha and OIII.
Once again, good work.
Very best,
Mike
|