Antelope Canyon is pretty surreal and a photography cheat code. You can pretty much just point a camera in any direction and get a pretty sweet shot. However, there are a lot of elements about Antelope canyon that will bring you back down to earth. Antelope Canyon is on Navajo land so there is no way to walk through Upper or Lower canyon without a guided tour. This means all those completely empty shots of the canyon are all manufactured moments between groups of crowds getting hustled through the canyon. Gotta have a quick trigger finger and find those little moments of solitude or shell out 5x as much money for smaller tours.
Upper canyon is likely where the majority of the photographs you've see are from. The canyon is way narrower which makes the light beams way more pronounced, however you need to be really calculated to score the conditions optimal conditions. Because the canyon is narrower, you'll need to track where the sun is at on the day you arrive. This means that in the colder months, the sun may never even get high enough in the sky to create any noticeable light beams. Upper Canyon is also super short and you need to take a short bus ride to even get to the canyon. Personally, we prefer lower canyon. The canyon is probably 4x longer than Upper canyon and is way less crowded so its easier to snag a last min spot if you aren't great at planning ahead (like we are). Basically, unless you are a hardcore nature photographer that is dead set on getting the same light beam shot (pictured below) that 10k others have already gotten, then you'll probably have a better experience at Lower.
If you aren't shelling out a ton of money for a private tour, you're going to want to be in the front or back of your group. In the front, you're going to want to sneak ahead of your group as often as you can. If you're in the back, pick a shot, let the group get ahead of you and take the shot quickly and keep up. If you let the group get too far ahead, you're guide will probably let you know it and keep you honest for the rest of the tour. As always, be nice/respectful to your guide....but at Antelope Canyon, this is especially true. If you're cool, you're guide will be cool and give you more of a leash to take better photos.
If you hate crowds, there are bunch of similar (but not quite as good) slot canyons nearby. You used to be able to just snag a permit and hike through the canyons solo, but now you need a guided tour. We did Canyon X and Secret Canyon prior to requiring a guide and tbh, now that they require guides, they're not worth it. If you're trying to decide between Antelope and one of these canyons, we would probably suggest just dealing with the crowds at Antelope...but do you.
When you think Arizona, you don't normally think cold weather. But we have been twice in the colder months and Page gets pretty damn cold. We have been in the area 3 times and the spring/fall time is definitely ideal. The sun starts getting high enough in the sky to get into the deep slot canyons for longer periods of the day and the temps are pretty ideal. In regards to crowds, since your only option is guided tours, there is no getting around this. They're pretty much booked every hour of every da, even in the winter months. However if you plan on going in the summer months, you better snag your spot pretty far in advance. If you do end up going in the winter months, we have gotten away with booking guides about 5 days in advance.
Antelope Canyon has two options, Upper and Lower canyon. If you want to see light beams, go to upper in the middle of the day. If you want to avoid the crowd and get a longer tour go to Lower Canyon. Best time of year to go is in the spring and fall. Best time to book a guide is in the middle of the day when the light is more upright and can reach the bottom of the canyon (for more even lighting). Despite being a super commercialized experience, Antelope Canyon is totally worth doing at least once. Just be sure you know what you're signing up for before you go and you won't be disappointed.