This is my recent 15x1mins O-III data applied as 50% luminance over a 14 x 3mins RGB image I took last year. It seems to improve contrast, darkening the darker (noisy and non-nebular) areas of an RGB image. At the same time it retains or enhances the detail in the brighter (nebulous) areas. Also, star coloration isn't as much affected as I thought it would be and I wonder why that is?
The reddish areas of nebulosity weren't eliminated either, which is the opposite of what I thought would happen.
This technique looks promising. I'm hoping (if it all works out) that it will let me collect RGB data on dark nights and O-III data on moon-affected nights. Maybe doubling the number of nights that I can collect data each month.
Certainly an O-III filter is a good buy for a DSLR. It's a nice new toy to play with while I save up for the modded D40.
