I've tried my first night photography of the stars last week. Most articles I've seen were recommending a fast lens, fully opened, @ ISO 800 and about 20 - 30s exposure, etc. Unfortunately, my only "fast" lens is a 50mm f1.4 which was fine but not as wide as I would have liked.
There is a strong possibility of aurora borealis tonight and I would like to use my wide angle lens (Canon EF 17-40mm f/4.0 L USM) With maximum possible aperture of f/4.0, what settings should I use to produce reasonably noise free photo. I would like to omit star trailing if possible.
I will be using a Canon 60D DSLR.