Take both -- what's a few more ounces? If weight is really an issue don't take extra shoes or something else. If you can absolutely take only one lens take the wide and crop. A tripod would be a plus if you can take it. In Utah beside Zion and Bryce go to Moab there is a wealth of photo opportunities there and nearby such as Dead Horse Point, Arches, Natural Bridges, Newspaper Rock, Hovenweep, Monument Valley and others.

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