When you're trying to take a photograph, intrusions aren't always welcome. While there are people out there who see a photographer and duck out of the way, there are also those who make no effort to dodge and instead offer up cheeky poses without being asked.
If you're good, you'll know when to let the intrusions happen, and then something fun can take place.
Johanna Siegmann is an architecture photographer who likes to shoot interesting buildings. She was out at the Ramon C. Cortines School of Visual and Performing Arts in downtown Los Angeles setting up her camera when a teenager rode across the frame just as Siegmann took the photo.