The motor-driven autofocus system in the lens provides quiet and smooth autofocus operation. Aperture Blades :9 circular aperture (150mm: F4.5-8 450mm: F5.6-8). To improve the convenience of the "Quick-shift Focus System," which allows manual focusing without switching from autofocus to manual focusing, three new switches, QFS/A, QFS/M, and MF, have been added.
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