It's quite rare to see aurora borealis in Helsinki, I've mostly only seen them around 400 km or more north.
Fairly weak and variable. I was only able to point my camera south and up, not north where the auroras normally are brightest - because of buildings and light-pollution in that direction.
As usual only green is visible to the naked eye, while the camera also picks up reds and maybe blues.
Canon 500D with 17-40/F4L lens at 17mm/F4 on tripd. iso400, 8-10 s exposure with cable-release.