NGC 7000 The North America nebula

This patch of nebuosity lies in the constellation Cygnus the swan . I was using a ten inch F4.8 reflector , PHD auto guiding and an Atik 383L mono CCD camera . I captured ten minute sub frames and matching dark frames and combined them with flat field frames to reduce vignetting in the final image . The total exposure times was 60 minutes using a H Alpha filter , 30 minutes using an O111 filter and 10 minutes for each colour filter:
Narrowband luminance with RGB colour:

Narrowband plus RGB:

Bicolour: