The pocket wizard allows you to control and fire your remote flash from a distance, up to 200 ft. Used with High Speed Sync (FP mode), this allows you to use a fast shutter speed on your camera in broad daylight and therefore open up the aperture for shallow depth of field — and beautiful out of focus background bokeh. The remore flash units fill in shadows on your subject for a perfect exposure.
In this video, the photographers took a different tack. Since they could not get their hands on a Sigma 200-500mm F2.8 lens but got the 800mm F5.6 lens instead, they relied on the long focal length to blur the background nicely. With such a long lens, the subject had to be quite a distance away but the pocket wizard units fired off the remote flash units perfectly, for the beautiful results you can see on the video.
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