The camera clicks before the shot, focuses and only fires one or two seconds later. How do I avoid the first click?

The first click occurs when the camera switches to live view. Avoid it by either switching live view off in dslrBooth or leaving it permanently on. Permanent live view, however, puts strain on the DSLR sensor and shortens its life.

To avoid the focusing delay, switch off autofocus on the lens and choose a small aperture for plenty of depth of field (f/8 to f/16). The flash power then has to be set considerably higher, and the focus is set manually once at the spot where guests will stand. Suitable basic settings for flash and camera are given in the FAQ Lighting behind the guests.