Antelope Canyon is amazing! The colors and textures - wow! The Navajo guide we had, Darryl, was great at pointing out the best picture shots, including what settings to use on cameras or phones. Often he would take our cameras and take the shot, including us in it. (Much better than selfies!) Our tour guide, Brad, was very knowledgeable, especially about Native Americans - both ancient and modern, as well as the geology and history of the area. We first stopped at Horseshoe Bend - very scenic, (and full of tourists from many countries). There is now a railing in place, so you can get close to the edge without fear of at falling. We had a picnic lunch, and plenty of water and snacks. Brad was very good at stopping for bathroom breaks (at Cameron Trading post), and after Antelope Canyon, we went over to Glen Canyon Dam (where the Grand Canyon starts).
I heartily recommend Grand Canyon Adventures. We had actually started the tour the day before, got to Horseshoe bend, and then Antelope Canyon closed due to threat of flash floods. (Our guide that day, Scott, was also knowledgeable and great.) The company offered either a full refund, or a re-book. We choose re-book and I'm glad we did, as Antelope Canyon was worth two days. It was interesting being with 2 guides, as they had different interests.