My favorites were Antelope Canyon and Arches. I think I would have liked Bryce as much as Arches if I hadn't gotten bad weather for that part. Sadly my trip was much shorter than yours will be (only one week).

I spent a day and a half in Antelope (upper and lower... definitely do both) with 35mm, and I thought that was adequate. With LF, I would suggest doing a day of scouting (perhaps with 35mm and get it developed at the one hour place to see what works). Once you know what compositions you really like, go back with the big camera. I want to go back one day and reshoot one particular shot with 4x5 (if I can find the spot again).

Arches would probably be good for several days as long as they aren't overcast. I spent two there.

Be willing to modify your itinerary based on weather. Some places need blue skies and some need cloudy.

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