As well as the outstanding imaging attributes, PENTAX engineers have raised the mechanical characteristics of the lenses to a state-of-the-art level. Built-in ultrasonic motors (Supersonic Motors) in the lenses provide for extremely quiet and fast autofocusing. Both lenses are also weatherproofed and protected from penetrating dust by appropriate seals. The front lens elements of the lenses use the special Pentax SP - "Super Protect" - fluoride coating technology. This nano-technology protects the front lens against dust, finger marks or smearing, making the lenses exceptionally easy to clean. The Pentax "Quick Shift Focus System" allows the photographer to manually alter the focus point at will without having to take the camera out of the autofocus mode.
Pentax 300mm F4 DA* Lens Features:
- Focal length: 300 mm (460mm in digital SLR format)
- Aperture range: F/4 - 32
- Optical construction: 8 elements in 6 groups
- Angle of view: 5.4° (with a PENTAX digital SLR body)
- Minimum focus distance: 1.4 m
- Magnification: 0.24x (1:4)
- Filter size: 77 mm
- Aperture control: Fully automatic
- Aperture blades: 9
- Lens hood: PH-RBK77 mm
- Lens case: S120-210
- Lens cap: O-LC77
- Diameter x length: 83 mm x 184 mm
- Weight: 1070 g
- Supersonic Motor
- Quick-shift Focus System
- SP (Super Protect) Coating
- Filter drawer
- Removable tripod collar