Quote:
Originally Posted by Peter Ward
As for city lights...with a 5nm filter I believe you could image from Pitt Street
or for less foot traffic, Observatory Hill and still get the same S/N.
..i.e. they are essentially immune to light pollution.  |
I have noticed a significant improvement in SNR after moving from Brisbane’s inner city to a small town. For example - good flats were essential even for 10-minute 3nm Ha subs on a moonless night, while in Prossy, as long as the bright one is not up, I can easily get away without flats when shooting 20-min 3nm HA subs, unless I’m chasing the faintest bits and stretching like mad. Background noise is much less here in Prossy in subs taken through 3nm filters, with the same scope and camera. Good narrowband filters like Astrodons help big time, but from my experience are not immune to strong light pollution. I strongly recommend a dark, or at least a darkish site
