Thanks everyone for the input. After reading the comments I asked someone else who was there for a few of their photos and they have similar issues - so I think the dusty haze must have at least played some part. (He was using a pocket digital and as he reminded me, there were a lot of people walking around kicking up dust). Thanks for the comments, I really appreciate the feedback.

Roger - thanks for the composition feedback. I'll try that advice on my upcoming trip.