The basis of the Kodak Laboratory Aim Density (LAD) concept is a simple inexpensive and easily used test film image to aid laboratories in making prints and exposing intermediates and internegatives in order to obtain good tone and colour reproduction in the final print. A standard film image with a patch with densities midway between the minimum and maximum densities is exposed on original camera film, and a duplicate negative is made that behaves in printing exactly like an original negative. This is the LAD image. The frame containing the LAD patch may be spliced into each film roll received by the laboratory for printing. The standard frame is then treated as a normal scene, and is always printed at the same printer balance settings. The rest of the roll (regardless of film type or origin) is graded relative to the standard frame using an electronic colour analyser, scene printer or trial print. There are specification densities for the large grey patch in the LAD Control Film which if followed throughout each printing or duplication stage will produce good tone and colour reproduction since achieving the aim density ensures that the range of densities falls on the optimum positions on the characteristic curves. These density values can be specified as aim values for a range of film stocks.