User manual SIGMA 310

[. . . ] This is due to possible focus shift resulting from extreme changes in temperature which cause various components in the lens to expand and contract. Special allowance is made for this at the infinity setting. DEPTH OF FIELD SCALE The depth of field scale helps you to check the depth of field (the zone of sharpness) of your composition. For example in figure (3), the depth of field zone is shown when the aperture F16 is used. NIKON AF TYPE CAMERAS This lens functions in the same way as a G Type auto-focus Nikon lens (without an aperture ring). [. . . ] (fig. 5) FILTER Only one filter should be used at the time. Two or more filters and/or special thicker filters, like a polarizing filter, may cause vignetting. When using a polarizing filter with AF camera, use the "circular" type. electrical contacts. Please keep them clean to ensure proper connection. To avoid damaging the lens, be especially sure to place the lens with its front end down while changing the lens. Many accessories such as rear mounted teleconverters, extension tubes, etc. , are specially made for designated lenses. Before you purchase such accessories, please check your Sigma lens to determine that it is compatible and that the accessories will function properly with it. BASIC CARE AND STORAGE Avoid any shocks or exposure to extreme high or low temperatures or to humidity. For extended storage, choose a cool and dry place, preferably with SETTING THE EXPOSURE MODE The sigma lens functions automatically after mounting to your camera. Please, refer to the camera instruction book. FOCUSING This lens features Sigma's built-in Hyper Sonic Motor (HSM). The HSM enables quick and quiet autofocusing. SIGMA AF and CANON AF For autofocus operation, set the focus mode switch on the lens to the "AF" position (fig. 2). If you wish to focus manually, set the focus mode switch on the lens to the "M" position. You can adjust the focus by turning the focus ring. NIKON AF , PENTAX AF, SONY and FOUR THIRDS For autofocus operation, set the camera to AF mode and set the focus mode switch on the lens to the "AF" position (fig. 2). If you wish to focus manually, set the focus mode switch on the lens to the "M" position. You can adjust the focus by turning the focus ring. [. . . ] When entering a warm room from the cold outdoors, it is advisable to keep the lens in the case until the temperature of the lens approaches room temperature. TECHNICAL SPECIFICATIONS Lens construction Angle of View Minimum Aperture Minimum Focusing Distance Magnification Filter Size Dimensions Dia. ×Length Weight 6­8 46. 8° 16 45cm (1. 48 ft) 1:7. 4 77mm 84. 5×68. 2mm (3. 33× 2. 69 in) 505g (17. 8 oz) Dimensions and weight include the SIGMA mount. camera's focusing mode. For Nikon, Pentax and Sony mounts, it is only possible to use AF with camera bodies which support motors driven by ultrasonic waves such as HSM. AF will not function if the camera body does not support this type of motor. [. . . ]