Backlight is a technique in which light is against the object that is being shot, so in a certain way the light is also against the camera lens. To create nice color effects, the leaves have to be hit by an intense oblique light like the one happening during sunrise or sunset.

For this picture I used a Canon Zoom Lens EF 90-300 mm, shutter speed was 1/60, aperture value: f/5, with a 400 ISO, during sunset in Puerto Limón Costa Rica.