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?