This spesific shot was done with a D7000 and a Tokina 11-16mm f2.8 (which is a lens that goes for canon, nikon and sony). When it comes to noise it's a cameradependant. I would recommend you to stay around 800 or 1000 ISO. As a general rule I normally overexpose my auroras by something lik 1,3-2,0 stops. And I always shoot with a wideopen lens, so f2.8
Apparently, I need to go to Norway if you get to see that, THAT often. Way cool. You are a wonderful photographer, and I'm almost surprised if you only started messing with it a year ago. You have a talent for it. Now, I have to follow you. Thanks a lot, adding to my to-do list and my "To-be jealous of" list. -.-
Since you put the shutter speed to 10sec.. so I assume that in real life the aurora beam will not look the same like this one in the photo (maybe it's lesser?).. O.O I haven't seen one in real life before but I really hope one day I could travel to your place and witness the nature's masterpiece!..
10s shutterspeed you get a more visible light, it's like natures own light painting, so if you use a shorter shutterspeed you kinda freeze a "dancemove" as with a longer shutterspeed you kinda get more of the dance in one image. if that makes sense?
Beautiful doesn't quite seem to cover it. You're so lucky to witness something like this. A stunning photo, I especially like how you've included the lights from the buildings below to really add a sense of scale.