Prom is a special event in the lives of many high school students: it marks their social transition from childhood to adulthood. The students can wear beautiful dresses and trim suits and their parents can snap photographs galore in an attempt to capture the moment. If you're going to be taking your prom photographs outside, you should remember a few key things about outdoor photography.
You should be aware always of what's going on behind you and how it complements or detracts from your desired aesthetic. Ensure that the colors of the flowers, the trees or whatever else is in the background works well with your dress. And make sure that the background is clear of unwanted items, such as vehicles, power lines, street signs and dumpsters; sometimes these items seem too far away or inconspicuous to be a nuisance but they become noticeable once pictures are developed.
You can't control the lighting when you take pictures outside; you have to work with what nature gives you. You should take your outdoor prom pictures during the daytime, when the sun is high in the sky. Hopefully the day will be sunny and not overcast. Ensure that those posing for the pictures are not facing the sun directly -- that will make them squint -- and that they're not faced away from it entirely -- that will place a shadow on their faces. Instead, shoot the couple or couples in the shade, where the lighting will be consistent.
For outdoor photographs, use your surroundings for props. Head out to a nearby lake and use benches, cast iron hand rails, and docks as your props. If you want that traditional prom arch look, find a botanical garden that has a flower or vine arch instead of bringing one made of balloons. You're already outside, you might as well make the most of what Mother Nature has provided.
You should employ a variety of poses and props during your photo shoot. Because it's impossible to fully discern the light properties and background details in a photograph until you look at it printed or downloaded on a computer, you should give yourself plenty of options from which to choose. If you find a background or scene you like, vary it a little by trying different angles or stances.