Depth of field calculation. Takes into account diffraction on an aperture for all colors in viewable range of wavelegths.Contains predefined profiles for over three hundreds digital cameras and backs and over six hundreds lenses manufactured by Canon, Epson, Fujifilm, Hartblei, Hasselblad, Kodak, Konika Minolta, Leaf, Leica, Mamiya, Minolta, Nikon, Olympus, Panasonic, Pentax, Phase One, Ricoh, Rokinon, Samsung, Samyang, Schneider, Sigma, Sony, Tamron, Tokina, Voigtländer.