I'm sure the shutter speed was min. 2 seconds. Close down the aperature to f/16 or smaller. It's probably more like f/22 based on the depth-of-field. The bottom was about to fall out, you can see the clouds rolling in over Broken Hand Pass which makes for good lighting. I shot from the same spot the next morning at sunrise but included the background b/c there weren't any clouds. Wish i were there now.
"As an adolescent I aspired to lasting fame, I craved factual certainty, and I thirsted for a meaningful vision of human life - so I became a scientist. This is like becoming an archbishop so you can meet girls."