The Pentax K-7 is a digital SLR camera, and though smaller and lighter than both the Canon EOS 50D and Nikon D300s, it has a traditional reflex mirror and an optical viewfinder. It also features a newly developed 14.6-million-effective-pixel CMOS sensor measuring 23.4×15.6mm with four-channel data read-out for faster image processing.
Pentax K-7 File formats
As with earlier enthusiast-level Pentax DSLRs, the K-7 allows images to be saved in one of two raw formats: the widely compatible Adobe DNG and Pentax’s own PEF format. As before, I have been unable to discern any difference between the quality of these two formats, but the choice has a small impact on the number of images that can be shot continuously.
When set to shoot in its high continuous mode, the K-7 can capture images at 5.2fps for up to around 30 premium JPEG images, 15 PEF or 14 DNG files. Also, the camera is ready to take another shot just a whisker faster after taking a PEF image than it is with a DNG file.
Pentax K-7 Shake reduction and built-in-level
Like the Pentax K20D, the K-7 has a sensor-shifting Shake Reduction (SR) stabilisation system and it is claimed to reduce the impact of camera shake so the camera can be handheld at shutter speeds approximately 2.5-4EV slower than usual.
A bit of lateral thinking has enabled this mechanism to be used in conjunction with the K-7’s built-in level, so the sensor can be set to rotate automatically by up to 2° to correct a sloping horizon. Those who prefer to trust the evidence of their own eyes, however, can use the level indicators marked in 1° to ±5° in both the viewfinder and LCD screen to guide the orientation of the camera in portrait and landscape format.
Pentax K-7 Sensor
In addition, when an image is being composed on the LCD screen with the camera on a tripod in Live View mode, the sensor can be shifted slightly to adjust the composition. As well as making noticeable vertical and horizontal movements, the sensor can be rotated by the user by up to 1° to level the horizon. I find it hard to imagine that a photographer will go to the trouble of using a tripod and almost get the image correctly composed before finalising it by shifting the sensor. Even when a rock or dry-stone wall is used to support the camera, the automatic correction is the easier option.
Pentax K-7 Other features
Pentax’s engineers have clearly put a lot of work into the K-7 and its specification has just about everything we would expect for a DSLR aimed at serious enthusiasts. The Live View system has contrast, phase and face detection AF, and the scene is displayed on the 3in, 920,000-dot LCD screen. There’s even high-definition video technology, which brings the camera into line with the market leaders.
There’s also automatic distortion and lateral chromatic aberration correction (with DA and DFA-series lenses), wireless flash capability and a multiple exposure mode. Although it features dynamic range optimisation settings (highlight and shadow correction), the K-7 is the first DSLR to feature an in-camera high dynamic range (HDR) option that combines three shots to make one composite image.
I found the in-camera level very useful with scenes that have sloping lines like this. The Window is perfectly level. The inset enlargement shows the smudging of detail in the edges of the frame with the new kit lens