The trees in the foreground set the tone for the desert location, but also cover a lot of the background. This is a difficult thing to comment on or assess without actually being there, but with a memorable background of the butte as subject, you may have to get out some hiking shoes and sneaker on over to a clearer foreground.
Sky is dark and seems to pop out that ridge - may want to look at the clouds though and bring them up to a bright white.
You really got some pop on the butte - but maybe it converted as a really high white, perhaps losing some of the subtle toning along the way. hard to say or evaluate.
A few words about landscapes, and this is tricky, is the wider angle lenses tend to add a better sense of recession and depth because they exaggerate the perspective. A 50 mm is like an effective 70 mm so you are getting a nice telephoto effect, but it will flatten out - so for something in the distance it works well, but for the high drama of the landscape you have to unfortunately get out and hike right up to the butte and pull out the 12 or 10 mm lens.
Hard to describe, but check out
Dave K http://www.usefilm.com/photographer.asp?ID=82314
or Patrick Di Frucia http://www.usefilm.com/photographer.asp?ID=35468
That is, if you can afford the time and cost! (I can't but always dream of trying someday)
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{K:13131} 6/15/2006
