Hello everybody,
about two years ago, I tried to make a bicolor of M 27. [OIII] is encoded in blue, H-beta is encoded red. In addition I generated a synthetic green channel from the sum of [OIII] and H-beta. The sketches I made during oberserving were made again with the same size, scanned and summed with color encoding. This is the result:
summe_2.jpg

I observed with a 24" dobsonian.

CS, Daniel