Hello Arthur,
I live in the Yukon Territory, Northern Canada, and we have northern lights often up here. I have shot lots of them, with print and slide film. I would suggest your Nikon, if you have anything in the f1.8 or f1.2, use your fastest lens. Everything will be taken care by the infinity focus, so shutter speed and film speed are the two other variables. Don’t use too slow of a shutter speed or they won’t be sharp. If the light is really bright you can get away with 1/30 or 1/15 at 100 iso. Got some good stuff on Velvia 50 iso, the colour saturation was amassing. Don’t be afraid to do double exposures, one for the lights and pop a little bit of flash in the fore-ground or use a flash light to bring in the ground. Including the ground give them scale, otherwise it’s hard to tell how big they are. The best lens I found for scale and perspective are, 50mm or at the most 35mm from tripod height, anything wider get real close to the ground. A 28mm or 24mm make them pretty small in the frame. One last trick, is to make a little housing for your camera with camping foam, the blue foam mat used to put under a sleeping bag. A bit of duck tape and foam, will keep the camera and your finger warmer. Ok, last thing really, go out even if you don’t see them, sometime they show up later in the night; and don’t chase them, find a good vantage point and wait. It’s like football, American or European… the action seems to always be on the other side of the field until you get there.
Have fun.
Mario
From the great white North.
