Wind is an issue. I recommend a faster film. LIke something in the 400 speed range. You don't need to "improve" the grain for contact printing and you will get at least one more stop out of that speed film. I was in the Big Bend National Park last summer and it was hot and windy. My shooting mate was prone to 100 (FP4) and was bitching all the time about the long times and slow shutter speeds. My film showed no movement at all. His did.