Hello all, I wish to use my 4x5 camera and a Fuji W 250mm f6.3 lens to take a head and shoulders portrait using window light. What aperture/shutter speed would I need with 400asa film to keep the sitters nose to ears in focus. Sould I be focusing on the tip of the nose, half way on the bridge of the nose or on the eyes? Also what would be the approx. distance between the camera and sitter when using a 250mm lens, would I be better using a 150mm lens instead?