I'm really interested in long exposure photography and will be shooting the coastline in the Pacific Northwest, plus landscapes mostly in Colorado. I have absolutely settled on Singh Ray filters as my brand choice, but I'm so torn on which one(s) to buy. I've narrowed it down to a few choices:
LB Color Combo filter (standard mount) stacked with a 10-stop Mor Slo (thin mount).
Vari-N-Duo filter (standard mount) all by itself. That would at least give me up to 8 stops of ND. No color intensifier effect, though. Then if I needed more ND later, I could buy a Mor Slo to stack on top of it.
I'm kind of leaning toward #1, although I know that that would give me less flexibility as far as the ND, since it's fixed at 10 stops instead of variable. But on the other hand, if I didn't need any ND, I could just use the Color Combo by itself and lose a minimal number of stops.