Flats in Mono Imaging

[SB]

The previous post led me to a question I never thought of before (especially as I am thinking about going to Mono):

Question: Do Flats need to be taken for each narrow band filter (using OSC I have used the same Flats for everything and not changed them for 12 months).

Thanks in advance.

Chris.

[The_bluester]

Yes, you flats for each filter as the dust bunnies and possibly vignetting will be different between them, and any time you change the camera angle you need a new set too (Unless maybe you are using a smallish refractor and rotating the entire scope in rings to change camera angle)


I normally shoot flats for each session. That is particularly required if you pull anything apart in the image train between sessions as dust bunnies can change session to session.