Hello.  I am currently enrolled in a black and white film photography class.  Our current project has to do with light, and I would like to try to take some star trail/field pictures.  I have done a little of this before on my DSLR, but to my great disappointment, the dark site I was at was still not dark enough to produce good trail pictures without severely brightening the image.  It's the darkest site anywhere close to me, in a yellow region for light pollution (from cleardarksky) , and I was just wondering how dark the sky actually has to be to do this properly.  Could I get away with a green or a blue region? Or will I have to go all the way to a black site?  I have a couple of weekends for this project, and I'm thinking about taking a weekend trip to some dark site farther away, but I would like to try to avoid it if I can.   Thanks!

Hi Mr Quasar. Here's a site that will answer most of the questions you've asked. I hope you find it helpful to you.