The ABC of Photography - Diffuser Any material that scatters the light as it passes through it, Softening the illumination and making shadows less distinct. Diffusers are commonly used with artificial light sources.…
Diffraction Scattering of light caused by deflection at the edges of an opaque object. Diffraction causes slight fuzziness in the image when the narrowest apertures are used. Sources: Pixabay, NASA,Wikipedia, Susan Wingfield…
Differential focusing Controlling depth of field to ensure that one element in the picture is sharp, while others are as out of focus as possible. Sources: Pixabay, NASA,Wikipedia, Susan Wingfield…
Depth of field A measure of how much of a picture is in focus, from the nearest point in the scene to the camera that looks sharp, to the furthermost point that…
Dedicated flashgun A type of flashgun that’s designed to provide direct one-way or two-way communication with the camera. The amount of dedication varies enormously depending on the flashgun and camera. Increased dedication tends…
Decisive moment The split-second when all the elements of a photograph simultaneously come together. The decisive moment is associated with Cartier-Bresson, who described photography as “the simultaneous recognition, in a fraction of a second,…
DC This features on the range of Sigma lenses that are designed specifically for use with crop-factor SLRs, and which can’t be used with full-frame models. Sources: Pixabay, NASA,Wikipedia, Susan Wingfield Lamar…
Daguerre, Louis Louis Daguerre (1787-1851) was an artist and inventor who devised one of the earliest photographic processes, the daguerreotype, announced in 1839. It was made by coating a silver-plated copper sheet with light-sensitive…
Darkroom A light-tight room for processing and printing Traditional photographs. Negatives are loaded into the processing tank in complete darkness, while a red/orange safelight can be used at the printing stage. Sources: Pixabay, NASA,…
DA Stands for Digital Auto, which features on a range of Pentax lenses that (unlike some earlier ranges) don’t have a manual aperture ring. They have a ‘Quick Shift’ mechanism that enables you…