Sony A77
Sony 70-400G @ 140mm
ISO 200, 1/640 @ f11
Chrissy and I just began our two week trip to Colorado and Wyoming with a stop at Great Sand Dunes NP. Most shots from the dunes usually depict the forms and shapes and I hope to get a bunch of those at sunrise tomorrow but today conditions were less classic including cloudy skies and high winds that kept a lot of people off the dunes despite the holiday weekend crowds. Here I wanted to depict the vastness of the place from the sage plains with the tiny scrub trees at the edge to the dunes themselves to the Sangre de Cristo mountains to the almost foreboding sky. Perhaps not a wall hanger but one I’m pleased with. All comments welcome. >=))>
Bill, nice image, I especially like the hazy look created by the blowing sand against the backdrop of the dark mountain. I think your composition does a good job of depicting the vastness of this location, and i like the amount of sky you included, a tight crop like this makes the mountain look more impressive. I could see including a very tiny bit more grassland, but that is a subjective nit.
My only suggestion for improvement would be to add a bit more midtone contrast in the dunes area, and slightly dodge the highlights of the blowing sand against the dark mountain. i played with doing these things using lights and darks luminosity mask selections, and it added a little more pop to the dunes and blowing sand. Overall this is a very nice image, and I think a few tweaks like dodging the blowing sand would take it up another notch.
Bill, this tells a fine story, with the color differences between the dunes and the mountains, the bit of grassland and the tiny trees. The haze due to the sand is an intriguing addition.
Bill,
Windy? Ya think? 
The plume of sand blowing off the top of the dunes is a dead giveaway.
Classic view and I think you captured it just right. Yes, you could play with the contrast and such, but the cold, overcast mood is captured well here. Just enough base and clouds up top. I suppose if you had a frame with more room top and bottom, I wouldn’t complain.
I hope you had a good sunrise this morning and you’ll have some images to share!
Lon