There are five ways:

• with the traditional and simple method of estimation that has been used for ages e.g. with the Hasselblad SWC (fixed 38-mm focal length) or the Linhof Technorama (exchangeable 58 to 250 mm focal lengths)

• with the help of a hand-held laser distance meter (extremely precise between 20 cm to ca. 30 m); such meters weigh less than 200 g, measure around 10 x 6 x 3 cm in size and are offered by Bosch, Leica Geosys-tems, Stanley and other manufacturers

• with the ALPA groundglass (with and without Fresnel lens, leather focussing bellows with integrated loupe or with the classic “black cloth”)

• all digital backs that come equipped with a small display screen offer the possibility of judging the sharpness and framing – this process can be repeated until the picture meets the photographer’s requirements

• There are digital backs that enable the user to determine framing and focusing on the screen of a connected computer already before the picture is taken. In their top DSLR range, e.g. Nikon and Canon have already reached a level of live view performance we would like to see with digital backs in a not too far future. It is probably not possible to reach such a level with the CCD sensors that manufacturers of digital backs presently use. May be only a change to another sensor technology such as CMOS will make such an improvement possible.