https://www.astrobin.com/gq7t1o/B/?nc=user
To create this file I used the Compose module:
S-II in Red channel
H-a in green channel
O-III in blue channel
The mix of colors is:
60% S-II + 40 H-a
30% S-II + 30% H-a + 40% O-III
100% O-III
The Compose module is easy and