It's fun to make travel photos more personal by including photos of the people you're traveling with in front of some of the landmarks that you're visiting together. Even if (like me) you prefer to rarely make an appearance in the photos yourself, you'll always be a part of the photos because you shot them. Taking pictures of your travel companions just standing there staring back at the camera can get old pretty fast, however, if you don't find some way to make the experience a bit more interesting for them and you.
One way to change things up a bit and get some interesting photos in the bargain is to use lenses, like ultra-wide-angle lenses, that were never really meant for portrait photography. To take this shot on the steps of Assateague Light in Virginia, for example, I used a Sigma 10-20mm ultra-wide-angle zoom (equivalent to 15 to 30mm on my Nikon D90 camera body) and a very low angle to stretch out both the doorway and my friend and make them both seem much taller than they are in reality. In order to get his very low angle, I had to literally lay down in the sand at the foot of the stairs and shoot nearly straight up. I also used the "live view" feature on the D90 that lets you compose on the LCD--a feature that I rarely use--to make composing the shot easier on my neck.
You can also get some interesting portraits by going the opposite way optically and using a very long telephoto lens to photograph someone in front of an unexpected background. You'll have to shoot from farther away, of course, but the compressed feeling that a long telephotos lens (any lens that is say, the 35mm equivalent of 300mm or longer) creates can be very eye catching. If you were to photograph someone standing on a street corner in Manhattan with a very long lens, for example, the compression would compact the spaces and press your subject into the traffic and crowds behind them. Your subjects will probably find the idea of posing a half block away more interesting too and they will no doubt feel more relaxed by not having to smile into a camera three feet away. (Just don't let them get so far away that they can escape on you.)
Whether you're shooting with a super-wide or super-long lens, take time to pause for a moment and show them the first few frames on the LCD. Once they see how off-beat the photos look they'll be more willing (hopefully) to pose a bit longer and be open to trying some of your extreme portrait ideas later in the trip.
The Treetop Temple in Kyoto of Kiyomizu-dera
13 hours ago