In reply to I'd rather be climbing:
Take a look at
http://www.lonelyspeck.com/focusing-at-night/
I've never had much success with the live view method mostly because wide lenses tend to mean smaller bright objects and more uncertainty. When the noise creeps up its hard to tell between noise and blur. Deep dark sky results in very little apparent exposure between foreground and sky. auroras are worse as they tend to be diffuse objects making life even more complex however an understanding of the above link can help.
Or buy a manual lens with a hard stop. Either the 16 mm fish eye or 24 mm f/2.8 AIS Nikkor are good bets. I've not tried but samgyang do a 14 mm with very little barrel distortion. I've got the sammy 24 mm tilt shift and I don't recommend it.
Check that they work correctly with your body.