Thanks! I ordered mine from B&H Photo. I started off with a couple Cokin filter sets (one grad, one solid) and they were in the $50-$75 range for a set of 3 different ones, haven't had any issues with them (the ones you get aren't the strongest but I stack them so it isn't too bad). I went cheap with getting a 10 stop, got a Formatt Hittech and it has such a bad color aberration that it's useless for just about anything besides a coaster (a $50 coaster). I've heard from a few other photographers that their firecrest line isn't bad but nothing good about the cheaper ones they make.

As for processing, I had to use the dehaze filter some because there was haze everywhere due to nearby wildfires. Other than that it was just a bit of tweaking the temp, contrast, and levels.