Cosmetic dentistry beauty & science

fortakingallofthecosmeticandsurgicalphoto- graphs required for your practice. _Camera system The most versatile camera for dental photo- graphy and for achieving the best results is without doubt a DSLR camera. A DSLR offers through-the-lens viewing and metering, precise focusing and accurate framing. The major advantage of DSLRs is that parallax is eliminated because the viewfinder, lens and image sensor all share the same optical axis. This means that what is seen in the viewfinder is identical to that recorded on the resulting image.4 The standard lens of a DSLR has a focal length of 50 mm; a shorter focal length lens, 28 mm for example, is classified as wide angled (e.g. for landscapes), while a longer focal length lens is a telephoto (e.g. for sport or wildlife). Fordentalapplications,adual-purposelensis necessary, firstly for portraiture and secondly to focus down for close-up photography. The ideal choice is therefore a lens that combines both these features, that is, a macro-telephoto lens. A word of caution about macro lenses: many compact cameras claim macro facilities but this only indicates close-focusing facilities; a true macro is capable of producing a 1:2 or 1:1 mag- nification. A 1:1 magnification is the ideal and means that the image recorded by the sensor is the same size as the object in real life. For 35 mm format DSLRs, a 1:1 image usually translates to about four maxillary incisors. Depending on the manufacturer and arrange- ment of optics within the lens barrel, the focal lengths of macro-telephotos vary from 50 to 1.05mm.Also,manysensorsaresmallerthanthe 35 mm film format and therefore have a multi- plication factor. For example, attaching a 100 mm lens to a 35 mm camera body will effectively in- crease the focal length of the lens to 150 mm, that is, the sensor has a multiplication factor of 1.5 (see below). However, some newer high-end cameras have larger sensors and therefore the lenses do not require a multiplication factor.4 It is difficult to recommend manufacturers or models of cameras because the market is rap- idly changing and new products are introduced annually.4 Commonly, Canon or Nikon DSLR cameras are recommended. A basic DSLR body with a 100 mm macro lens can be purchased at many photography stores or online. Settings for optimum results As cameras will commonly require about a 1.5 times increase (conversion) in the setting on Figs. 2 & 3_Camera-mounted electronic flashes. Fig. 4_Aperture settings. I 21 special _ digital photography I cosmeticdentistry 3_2013 Fig. 3 Fig. 4 Fig. 2