Filters question

[PaulR1]

Hey guys ...

 

Would I be right in assuming that if you use narrowband filters then you dont need to worry about also having a light pollution filter installed ?

 

[symmetal]

Yes, that's right. If the LP filter blocking frequencies included your narrow band frequency you would be blocking the very band you wanted to image. If the LP filter blocking frequencies didn't include your narrow band frequency then it would have no effect in blocking LP from your image so would just be an extra piece of unnecessary glass in the way and would slightly degrade your image.

Alan

[kirkster501]

Correct.  No need for a LP filter at all with NB.

However, with my Astrodon filters, I have removed the LP filter for LRGB as well, I was finding that 10-15 minute subs did not appear significantly diifferent with the LP on or off, so I removed it (and may sell it).

[tomato]

You could consider NB filters to be the ultimate light pollution filter as they block out large portions of the ‘natural’ spectrum as well as man-made unwanted light.