Here is an image of B33 taken using a blue filter on two separate evenings. To prevent the stars from saturating I only captured 60 second sub frames with matching dark frames. I then combined them with flat field frames and bias frames to reduce the effect of vignetting in the final image. The total exposure time was two hours. The colour data were taken using H-alpha for red O111 for green and aditional blue filter for blue. plus a combination of old RGB data.
Captured through a blue filter
Final colour image
