Hello all! I’m sitting at home at my bortle 8(ouch) location which at the moment only has a good view to the north. I recently acquired a 2” astronomik 12nm H-alpha filter to use with the artesky adapter I have which is currently holding a 2” L filter for my 294mc pro for rgb, and for luminance with the 2600mm on the rasa 8. What I’d like to do is image in Ha with the 2600mm since I’m in pretty heavy LP, but there isn’t much in the way of heavy Ha targets out that way right now, so I figured I could image m106 since it has very nice Ha structures. Then I can get an rgb image to combine with later, or share the data with someone that wants to combine some Ha to their image and make a collaborative effort.
The thing I need advice with, is how long should these exposures be?(approx.) With the 2600mm/rasa 8 and the L filter, I was still blowing out some pixels(around 400 per sub) even at only 30” at 0 gain. But I know narrowband is a totally different animal and I’ve never shot NB before. Is there a “rule of thumb” with how much longer than your L subs your Ha subs should be? Like 2x, 3x, 4x, or something along those lines? I’d prefer to keep using 0 gain as the dynamic range of this camera is incredible, and I plan to always use 0 gain with the rasa.
So with the info I’ve provided, where would you start experimenting as far as sub lengths for Ha with a 2600mm on an f/2 system? I know it won’t be a clear cut answer, just looking for some kind of starting point as having never done nb before, I don’t wanna start somewhere “way out of the ballpark” and waste a night of imaging. Thanks everyone and clear skies!
Edited by Professor2112, 10 April 2021 - 06:49 PM.