To continue with the Yellowstone photos (I posted a bunch of wildlife photos in the wildlife forum) here is some of the weather we saw while there. All shot with the Pentax K20 and Sigma 17-70 (wildlife shots were with the 40d and 400 f/5.6 L while my landscapes shots were all with the Pentax system).
I took this is 2 .6 ND filters stacked. I was trying to get long exposures to capture some lightning. The nice thing was that this was happening right before sunset which gave some incredible light.
3s f/20.0 at 17.0mm iso100
3s f/20.0 at 23.0mm iso100
8s f/20.0 at 17.0mm iso100
1/25s f/8.0 at 28.0mm iso100
1/320s f/8.0 at 53.0mm iso100
1/320s f/8.0 at 17.0mm iso100
1/400s f/8.0 at 17.0mm iso100
1/125s f/8.0 at 17.0mm iso400
, 135mm f/2.0
