I just returned from Joshua Tree. Here are my thoughts: Cholla in the morning. The backlight from the rising sun is better than that available in the evening. The wind was calm in the mornings and picked up by the late afternoon in almost all areas of the park. Keys View, in my opinion is too hazy to really capture the valley at sunrise or sunset. I went to Keys View for sunrise and in the afternoon. When I visited in the afternoon the wind was unmerciful. The morning I imaged was very calm and quiet. It was a beautiful sunrise, but I think I could have a better image from the valley with a Joshua tree. My advice is to explore the tree/rock combinations for sunrise and sunset in the Hidden Trail area. Best of luck.