|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.|
|DA||Autofocus lens for Pentax APS-C digital SLR cameras. Has no aperture control ring and only supports electronic aperture control from the camera.|
|ED||The lens incorporates low dispersion elements to minimize chromatic aberrations and ensure excellent sharpness and contrast even at maximum aperture.|
|AL||The lens incorporates aspherical elements to minimize spherical aberration, astigmatism, coma and ensure excellent sharpness and contrast even at maximum aperture.|
|[IF]||The lens has internal focusing. Learn more|
|Diagonal angle of view:||99.3°-61° (Pentax APS-C)
|Lens construction:||13 elements in 11 groups, including:|
|Number of blades:||8|
|Closest focusing distance:||30 cm|
|Type of autofocus motor:||No motor|
|Full-Time Manual Focus:||Yes|
|Maximum diameter x Length:||Ø84 x 87.5 mm|
|Filter size:||77 mm|
Design and Features
The lens is a result of cooperation between Pentax and Tokina companies and is known as Tokina AT-X Pro 124 AF SD 12-24mm F/4 (IF) DX in Canon EOS and Nikon F systems.
During the partnership between Pentax and Samsung to develop digital SLR cameras with interchangeable lenses this lens was produced by Pentax since September 2006 under the Schneider-Kreuznach D-Xenon and later under the Samsung label for Samsung GX series of digital SLR cameras with Pentax K mount.
The lens barrel is of moderate weight, made of plastic. The lens mount is metallic. The zoom ring is wide, rubberized and deeply ribbed in order to provide good grip and prevent slippage of fingers. The lens has a distance scale.
The lens has rather narrow focal range. Formally it is the disadvantage, however in practice it contributes to a good compensation of optical aberrations and equally high image quality at the entire focal range.
The lens uses front filters with standard size of 77 mm which are easy to find. However, filters of such size are more expensive and mainly used with professional lenses.
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).
Warning: vignetting occurs at focal lengths below 15 mm with most filters (except for some slim filters).
Dedicated petal bayonet lens hood (a part of the package) features a slide-out window which enables rotation of polarizing filter without removing the lens hood.
The lens lacks built-in motor, the autofocus is moderately noisy but fast. 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.
The focusing ring rotates during autofocus which looks pretty anachronistic by today's standards. It is strongly recommended not to touch the ring or manually stop its movement because it might result in damage to the lens and/or camera.
|Sensor size:||23.5×15.7 mm|
|Distortion at 12 mm:||-2.11 %|
|Distortion at 24 mm:||-0.15 %|
|Vignetting at 12 mm F/4.0:||-1.12 EV|
|Vignetting at 24 mm F/4.0:||-0.46 EV|
Alternatives (AF, 10-27 mm)
|Sigma 12-24mm F/4.5-5.6 DG HSM II||2011||⊗|
|Sigma 12-24mm F/4.5-5.6 EX DG Aspherical HSM||2003||⊗|
|Tamron SP AF 10-24mm F/3.5-4.5 Di II LD Aspherical (IF) B001||2008||⊗|