The lens produces an amazing image quality with stunning bokeh regardless of focusing distance. With 8 rounded aperture blades, the background blur and the transition from sharpness to blur become smooth and pleasant.
Lens construction consists of 10 elements in 8 groups. One ED (Extra-low Dispersion) glass optical element and two Anomalous Dispersion glass optical elements compensates for various aberrations and minimizes unwanted purple fringe effects. This is coupled with the high-grade, multi-layer HD coating, which reduces average reflectance in the visible ray spectrum to less than 50 percent compared to conventional models, and the innovative FREE (Fixed Rear Element Extension) focusing system.
The 100mm macro features Pentax well-renowned dustproof, weather-resistant AW (All Weather) construction using six sealing parts to optimize airtight performance. SP（Super Protect) coating applied to the front optical element keeps the front surface free of dust or stains and ensures use even in the harshest weather conditions.
The focus ring features the Pentax Quick-Shift Focus System, which allows the photographer to instantly shift focus mode from auto to manual after the subject has been captured in focus by the camera’s autofocus system. This single-action operation assures a smooth, comfortable focus-mode switching maneuver during manual-focus shooting, for dramatically improved operability.
- Great optical construction
- AW construction using six sealing parts
- Pentax Quick-Shift Focus System
- Minimum focusing distance 0.303 m