The K100D is the first Pentax digital SLR to feature built-in Shake Reduction, this operates by stabilizing the CCD sensor, while similar to the Anti-Shake feature seen in Konica Minolta (and now Sony Alpha) digital SLR's Pentax claim their system is superior because it is the only fully 'free floating' design which allows it to correct for not only movement on the x and y axis but also rotation on the z axis (the twisting motion around the optical path).
The stabilization test
This test was first used in our Sony DSLR-A100 review, twenty hand-held shots were taken of a static scene, half of those with stabilization, half without, the shutter speed was decreased by a stop and repeated (from 1/80 sec to 1/10 sec). The lens used was the Pentax 50 mm F1.4 (producing a 75 mm equiv. FOV), the test chart was 1.2 m away from the camera.
The resulting 80 images were then inspected and given a blur score from zero to three where zero represented a very blurred image and three a sharp image with no noticeable blur (see crop examples below). Obviously the amount of blur which is acceptable will depend on your personal taste and the final image size (for instance a '2: Soft' will still look fine as a 4x6 print or in a web gallery). Example crops from these four blur scores can be seen below.
|0: Very blurred||1: Blurred|
|2: Soft||3: Sharp|
Hand-held, no stabilization (50 mm lens, 75 mm equiv.)
As you can see from the results here we managed to get nine sharp shots at 1/80 sec which dropped to five at 1/40 sec and three at 1/20 sec.
Hand-held, with Shake Reduction (50 mm lens, 75 mm equiv.)
Utilizing the K100D's Shake Reduction did improve things, but only slightly. At 1/40 sec it achieved an extra three sharp shots, and 1/20 sec an extra two sharp shots. Kudos to the Pentax SR system for delivering more sharp shots but it's clear that it's no substitute for increased shutter speed or a tripod.