Pentax SMC-DA 15mm f/4 AL ED Limited - Review / Test Report
Lens Reviews -
Sunday, 18 October 2009 20:00
Page 1 of 3
Special thanks to Armin Daum for providing this lens for testing purposes!
The Pentax SMC-DA 15mm f/4 ED AL Limited is a new so-called pancake lens for Pentax APS-C DSLRs. The field-of-view of this lens is equivalent to about 23mm (in full format terms) so it's on the verge of being a wide to ultra-wide prime lens. As you can observe below pancake lenses are pretty tiny beings - this one has a length of just 40mm. Pentax has quite a tradition here by now and these lenses are definitely a differentiator compared to other systems.
The DA 15mm is a designated "Limited" lens - these lenses are made of high quality materials in a mainly manual assembly process and they enjoy an above average quality control. They're produced in "limited daily quantities" ... which sounds a bit like odd marketing blabla to me. The DA 15mm Ltd is certainly a very high quality item with all parts made of metal and made with tight tolerances. The tiny focus ring operates very smooth and slightly damped. The inner lens tube retracts/extends marginally during focusing operations. The front element does not rotate so using a polarizer is no problem. The lens has a build-in petal-shaped lens hood (telescope style) which is very handy - it's quite amazing that Pentax managed to implement such a mechanism into this tiny lens.
Typical for most Pentax lenses the DA 15mm f/4 has no internal AF motor and relies on a slotted drive screw operated by the camera. Consequently AF operations generate a moderate degree of noise. The AF speed is very fast on the K10D - there isn't really much to move around here anyway. Thanks to a "Quick-Shift Focus System" manual focusing is instantly possible once the AF has achieved focus.
|Equiv. focal length||22.5 mm (full format equivalent)|
|Equiv. aperture||f/6 (full format equivalent, in terms of depth-of-field)|
|Optical construction||8 elements in 6 groups inc. 1x aspherical and 1x UD element|
|Number of aperture blades||7|
|min. focus distance||0.18 m (max. magnification ratio 1:6.7)|
|Dimensions||63 x 40 mm|
|Filter size||49 mm (non-rotating)|
|Hood||petal-shaped, build-in (telescope style)|