| SMC Pentax-DA* 55mm f/1.4 SDM | |
| Key features | |
|---|---|
| Maker: | Pentax |
| Ultrasonic motor: | Yes |
| Macro capable: | No |
| Unique features: | Weather-resistant |
| Application: | Portrait |
| Technical data | |
| Type: | Prime |
| Focal length: | 55mm |
| Focal length (35mm equiv.): | 82.5mm |
| Frame coverage: | APS-C 1.5x |
| Aperture (max/min): | f/1.4 / f/22 |
| Construction: | 8 groups / 9 elements |
| # Diaphragm blades: | 9, rounded |
| Close focus distance: | 17.76 in (0.45 m) |
| Max. magnification: | 0.173x |
| Physical | |
| Max. diameter: | 2.8 in (70.5 mm) |
| Max. length: | 2.6 in (66.0 mm) |
| Weight: | 13.2 oz (375g) |
| Filter diameter: | 58mm |
| Accessories | |
| Lens hood: | PH-RBH 58mm |
| Case: | S90-100 |
| Angle of view | |
| Diagonal: | 28.6° |
| History | |
| Introduced: | 2008 |
| Retail info | |
| MSRP US$ | $799.95 |
The SMC Pentax-DA* 55mm f/1.4 SDM lens is a professional prime lens for the Pentax K mount. It is designed for portrait use[1] with a 35mm equivalent focal length of 82.5mm. The lens features weather sealing, an SDM ultrasonic motor for quiet autofocus, and has 9 rounded diaphragm blades for smoother bokeh. However, the autofocus accuracy varies by camera body and is not especially fast[2].