A frequently asked question is which is tour is better between Upper and Lower Antelope.
Upper Antelope is considerably more popular both in overall visitation and people in the canyon at one time. A common complaint over the years is how crowded Upper Antelope can by. However, you would be hard pressed to be able to tell the difference in photographer between the two canyons.
Lower Antelope is just as beautiful as Upper Canyon, but has serious mobility issues for anybody with joint or strength issues. At a minimum, you must be able to climb multiple ladders at high incline.
The reward for this is that you will be in the canyon with 10x less people. Upper canyon is only 300 feet long, and can easily have 100 people in it at a time. Lower canyon usually has significantly less people that that. In addition, Lower Antelope is a one way hike, so it helps manage the flow of visitors.