|SMC||The super multi-layer coating is applied to the surface of lens elements. It boosts light transmission, ensures sharp and high contrast images, minimizes ghosting and flares. The smc coating is used in all Pentax K, 645 and 6x7 lenses and also in Asahi Takumar M42 lenses since 1971.|
|D-FA||Full frame autofocus lens for Pentax digital SLR cameras. Has no aperture control ring and only supports electronic aperture control from the camera.|
|MACRO||Macro lens. Designed for close-up photography.|
|Position in the lineup|
|smc Pentax-D FA 50mm F/2.8 Macro||1:1||Aug 2004||⊗|
|smc Pentax-FA 50mm F/2.8 Macro||1:1||1990||⊗|
|smc Pentax-F 50mm F/2.8 Macro||1:1||1988||⊗|
|smc Pentax-A 50mm F/2.8 Macro||1:2||1984||⊗|
|Maximum format:||35mm full frame|
|Diagonal angle of view:||46.8° (35mm full frame)|
|31.6° (Pentax APS-C)|
|Lens construction:||8 elements in 7 groups|
|Number of blades:||8|
|Closest focusing distance:||19.5 cm|
|Closest working distance:||4.7 cm|
|Magnification ratio:||1:1 at the closest focusing distance|
|Type of autofocus motor:||No motor|
|Full-Time Manual Focus:||Yes|
|Maximum diameter x Length:||Ø67.5 x 60 mm|
|Filter size:||49 mm|
Design and Features
The lens barrel is compact, of moderate weight, made of plastic. The lens mount is metallic. The rubberized focusing ring is wide, deeply ribbed in order to provide good grip and prevent slippage of fingers, well damped, moves smoothly in manual mode. The whole optical system of the lens extends considerably with focusing from infinity to the closest distance. The front element is not deeply recessed inside the lens barrel, as in case of most macro lenses, therefore a deep round lens hood (a part of the package) could be useful sometimes. Like all Pentax FA series lenses, this model is equipped with the distance scale behind a window and aperture ring. Additionally, the lens has a magnification scale.
The aperture is controlled by the camera as long as the lens's aperture ring is set to its "A" position. To set the aperture ring to “A” or another specific position, hold down the aperture lock button and turn the aperture ring to align the desired position with the red-line index. The click stops on the aperture ring indicate the following f/numbers: 32 - 22 - 16 - 11 - 8 - 5.6 - 4 - 2.8.
The lens is equipped with a CLAMP switch which is convenient for manual focus: focus manually then set the CLAMP switch to ON. The point of focus will be locked. Autofocus will also be disabled.
The lens uses front filters with standard size of 49 mm which are easy to find. They are also inexpensive. It should be noted that most lenses of the system have such diameter of the filter thread, that is why if you will purchase additional lens with similar focal length and/or speed, you probably will be able to share filters between them.
The filter thread does not rotate during focusing which allows convenient use of different types of filters (including but not limited to polarizing and gradient).
The lens lacks built-in motor, the autofocus is moderately noisy and relatively slow. Moreover, the autofocus is prone to hunting at close focusing distances. The autofocus could have been more effective if the lens was equipped with focusing range limiter. Unfortunately, such functionality is not available. The lens features Quick-Shift Focus System: after autofocus is achieved, the focusing ring can be turned to adjust the focus manually. This feature eliminates the need for changing the focus mode to MF.
For general information on macro lenses please refer to the article dedicated to Canon EF 100mm F/2.8 Macro USM
The lens incorporates a floating system that provides correction of aberrations and ensures constantly high image quality at the entire range of focusing distances from infinity down to the closest focusing distance. Learn more
The sharpness is excellent across the APS-C frame already wide open.
|Camera:||Pentax K-5 II|
|Sensor size:||23.7×15.7 mm|
|Vignetting at F/2.8:||-0.67 EV|
Alternatives (AF, 44..56 mm)
|Sigma 50mm F/2.8 EX DG Macro||1:1||2004||⊗|