Automatic close-up shackle group (Canon) Close-up meet circle DG CANON AF AF close-up shackle. Close-up after 13/21/31 hoop set suits. The Canon EOS bayonet automatic focusing. The dynamic close-up by trap is equipped with three quarter length (31 mm respectively, 21 mm and 13 mm) of different circles, the magnification can be any combination to need. The circle can fit the fuselage TTL metering and AE model, AF version can cooperate with CANON, Minolta AF and CANON AF airframe function of AF also can cooperate Minolta Xi series electric zoom lens. CANON AF DG, the domestic trading. Close-up meet circle is internal tubular close-up attachment to black, made of metal. Usually 35 mm camera often use of circle is divided into 7mm (1), 14mm (2) and (3) three 25 mm, they can be used alone or in combination to use, and can be composed of seven different length. Close-up meet circle has the advantage of small volume, light weight, easy to carry; Some automatic answer the ring with the aperture of the camera linkage; Tube structure is extremely simple, general is not easy to damage. Disadvantage: the depth of field is too short, focusing process is relatively easy; Amount of the optical lens will be affected. Can be used for remake, divided into 1.2.3. Three rings, cooperate to use, free combination to achieve the best effect. For example: lens focal length 50mm focus distance to infinity - 0.6mm. The scene within 0.6 M can't shoot, According to the different combination of three connecting link, and can realize different magnification. Take the F=50mm for example, close-up connect ring combination than as the adjusting range (approximate) 1:0.20~1:0.34 1 1:0.34~1:0.48 2 1:0.48~1:0.62 1+2 1:0.62~1:0.76 3 1:0.76~1:0.90 1+3 1:0.90~1:1.04 2+3 1:1.04~1:1.18 1+2+3 1:1.18~1:1.32.