Pentax SMC-D FA 100mm f/2.8 macro - Review / Test Report
Lens Reviews - Pentax
Tuesday, 25 December 2007 23:37

Special thanks to Jens Rösner for providing this lens!


The Pentax SMC-D FA 100mm f/2.8 is one of two macro lenses in the current Pentax lens lineup. It has been released fairly recently but it is obviously not a DA-type lens - it does still support the full (35mm) format and Pentax implemented a dedicated aperture control ring. Compared to its predecessors the new lens features an "optimized lens coating and positioning of optical elements" for the special characteristic of today's image sensors. On current APS-C DSLRs the field-of-view is equivalent to about 150mm (full format).

The DFA 100mm f/2.8 macro is very different from its older cousin (FA 100mm f/2.8 macro) - it not heavy metal block but mostly a plastic-fantastic lens which doesn't feel quite as durable. The inner lens tube wobbles a bit. Obvious advantages of the new design are the very compact dimensions and a very low weight. Typical for most medium tele macro lenses the inner lens tube extends significantly when focusing towards short focus distances.

The DFA 100mm f/2.8 has no internal AF motor and relies on a slotted drive screw operated by the camera. The AF is comparatively fast but it tends to hunt a lot and unfortunately Pentax did not implement a focus limiter which could help here.

Equiv. focal length150 mm (full format equivalent)
Equiv. aperturef/4.2 (full format equivalent, in terms of depth-of-field)
Optical construction9 elements in 8 groups
Number of aperture blades8
min. focus distance0.3 m (max. magnification ratio 1:1, min. working distance: 13cm)
Dimensions67 x 81 mm
Weight345 g
Filter size49 mm (non-rotating)
Hoodbarrel-shaped, snap-on type (supplied)-
Other featuresFREE (Fixed Rear Element Extension) focusing system