Digital SLR

The new Pentax K200D replaces the K100D and is targeted at family users and digital SLR beginners. Although its 10.2-megapixel CCD image sensor has lower resolution than the 14.2-megapixel CMOS chip in the K20D, the entry-level K200D has similar dust- and moisture-proof sealing, the same built-in anti-shake and dust removal and many of the same functions, but a significantly lower price tag.

The review camera was supplied with the smc Pentax DA 18-55mm f/3.5-5.6 AL II lens, which is an updated version of the lens as we used for the K20D review. Modifications that make the K200D a significant improvement on the previous model are listed below:
1. Increased sensor resolution from 6.1 megapixels effective to 10.2 megapixels effective.
2. A new PRIME image processor with (Double Data Rate 2) RAM components to ensure fast data processing and file transfer.
3. A larger, 2.7-inch LCD with slightly higher resolution and a wider viewing angle.
4. Support for high-capacity SDHC memory cards.
5. A separate, programmable RAW button for direct access to raw file capture.
6. An Expanded Dynamic Range function, which reduces the sensor's sensitivity range to ISO 200-400 and captures shadow and highlight detail in high-contrast scenes.
7. A Dust Alert System for locating dust spots to make sensor cleaning easier.
8. A Digital Preview function that allows users to preview shots on the camera's LCD (but does not support full live view shooting).
9. Improved power management with battery consumption reduced by a factor of eight.
10. An optional battery grip with 14 dust- and moisture-proof seals.

On the downside, the K200D's flash is not as powerful as the K100D's, which had a GN of 15.6, although our tests (see below) showed the flash to be a good performer. Size-wise the new model is a little larger than the 6.1-megapixel K100D and 100 grams heavier.

Body and Controls
The K200D's body consists of a metal chassis with a fibre-reinforced plastic housing.  Protective sealing has been applied to 60 areas in the K200D's body (compared with 74 areas on the K20D). Sealed areas include the shutter release button, switches, levers and dials, making the K200D the only dust- and weather-proof DSLR camera in its class. Like its predecessor, K200D uses four AA batteries as its power source.

The overall body design is quite similar to the K20D, although some controls are in different places and the mode dial carries more settings in the entry-level camera. The handgrip is large enough for comfort and the shutter button is well positioned. Surrounding it is the rotating switch for selecting off, on and preview modes.

The digital preview function lets users check shot composition and exposure levels before shooting. It's not the same as the live view shooting mode on the K20D because it doesn't support image capture. Pressing the shutter button ends the preview and re-engages the AF system (which is disabled in the preview mode). However, you can display the histogram or bright/dark area warning signals by selecting these settings in the Digital Preview section of the playback menu.

As in the K20D, you can save the preview image as a JPEG file by pressing the Fn button in digital preview mode. Digital preview shuts down automatically after 60 seconds.

Behind the shutter button lie the combined AV and exposure compensation button and a Green button that sets the camera to automatic exposure.  This button accesses a new Auto Picture mode, which automatically sets the most appropriate shooting mode (such as Portrait, Landscape and Macro) for a given subject or scene and adjusts white balance, saturation, contrast and sharpness levels, allowing the photographer to concentrate on shot composition.

In addition to the now-standard Pentax P, Sv, Tv, Av, M and Bulb shooting modes the K200D includes seven scene modes that can be tweaked manually. The rear panel has the same LCD, AE lock and function buttons as the K20D. The same array of buttons lines up left of the LCD. However, the exposure bracketing button on the K20D is replaced by a button for popping up the flash and the K200D has an arrow pad instead of a control dial.

The anti-shake switch, which activates a similar function to the K20D's, is now a slider instead of a lever. There's also no lock on either the SD card compartment or the battery compartment, although both close quite securely. The viewfinder is also different in the K20D,  combining a lightweight penta-mirror with Pentax's Natural-Bright-Matte II focusing screen, which is not interchangeable.

It offers 96% field-of-view coverage plus 0.85x magnification. A slider above the eyepiece provides dioptre adjustment from -2.5 to +1.5 dpt and the eyepiece has a soft rubber eyecup. A strip display below the frame provides status indicators for most shooting functions, including icons for selected scene modes.

The sensor dust removal system is the same as the K20D's and involves a three-step system. A special anti-static coating on the low pass filter repels dust, while vibration of the filter dislodges any dust that may have settled. Finally, an adhesive strip in the mirror box collects the dislodged dust, preventing it from being distributed around the mirror box.

Other features shared with the K20D include the shutter speed range, optical image stabilisation system, 16-segment metering and 11-point AF system with 9 cross-type sensors. Kelvin adjustments for white balance are also provided, as is white balance fine-tuning. Pentax has given the K200D 13 fewer Custom Functions than its higher-resolution sibling but they probably won't be missed by the target market. Menu design and playback options are very similar in the two cameras.

The K200D is supplied with the same software bundle as the K20D. It includes Pentax Photo Laboratory 3 RAW data processor and Pentax Photo Browser 3 browser.  The K20D also comes with Pentax Remote Assistant 3, camera control software. For details of the software bundle and supported playback modes, see the review of the K20D. An optional battery grip (D-BG3) is available to extend shooting capacity and provide a vertical shutter release. 

Sensor and Image Processing
Whereas Pentax has opted for a CMOS sensor in its K20D 'pro-sumer' model, in the K200D it has taken the 10.2-megapixel chip from the popular K10D for the K200D and housed it in a lighter, more compact body. We estimate this imager has photosites with a surface area of 6.07 microns square, which is reasonably large.

Coupled with the sensor is the Pentax Real Image Engine (PRIME) image processor, which may be the same as the processor in the K10D, given the fact that the K200D inherits the same buffer memory and drive speeds for continuous shooting. In high-speed mode, up to four frames can be recorded at 2.8 frames/second. This restriction applies equally to both high-resolution JPEGs and raw files. With the Low setting, JPEG files can be recorded at 1.1 frames/second until the memory is full but the four-frame limit for raw files still applies.

Like the K20D, the K200D records image data on SD or SDHC memory cards. JPEG files can be captured in one of three sizes: 3872 x 2592, 3008 x 2000 or 1824 x 1216 pixels and at three quality levels. Raw files can be recorded in both PEF and DNG formats. Typical file sizes are shown in the table below.

The K200D appears to have the same 14-bit in-camera raw file converter as the K20D and supports similar raw file processing facilities. However, it only allows converted files to be saved as JPEGs. JPEG size and quality parameters can be adjusted and adjustments can be made to white balance, sensitivity, image tone, saturation, sharpness and contrast. Similar pre-capture image adjustments are also provided, covering saturation, sharpness, contrast and colour (including monochrome settings).  

Performance
Pictures from the test camera had a superficial resemblance to our test shots from the K20D, particularly with respect to the extended dynamic range provided by both cameras. However, the K200D showed less inclination to bias exposures slightly in favour of recording highlight details and the yellow-brown cast we found in test shots taken with the K20D shots was much less evident.

The results of our Imatest assessments produced some different (and very interesting) results from the cheaper camera. From these tests, it seems the file format you use for shooting and the way you convert raw files can have a definite bearing on the resolution you obtain.

With JPEG files, Imatest showed the test camera to be capable of meeting the resolution standards we expected of a 10-megapixel camera. In fact, at times the results slightly exceeded the expected levels. Resolution was highest at the longer focal lengths and towards the middle of the aperture range. The graph below plots the results for our Imatest assessments for JPEG files taken with the various focal length and aperture settings provided by the kit lens.

With DNG.RAW files that were opened in the Imatest software (which contains a raw file converter), the results were somewhat better. However, when PEF.RAW or DNG.RAW files were converted into TIFF format using Adobe's Camera Raw converter we obtained outstanding results, as shown in the Imatest graphs below.

Interestingly, the conversion process delivered files with reduced saturation, which is ideal for further editing. Very few colour shifts resulted from the conversion process and the shifts that occurred were minor. In contrast, JPEG files tended to have similar saturation levels to shots from digicams and more pronounced colour shifts.

Imatest showed resolution to be highest at the longer focal lengths and with ISO 100 and 200 sensitivity settings. A noticeable decline in resolution occurred at ISO 400, with a further step down to ISO 800 and 1600 (and little difference between these settings).

Lateral chromatic aberration was negligible at focal length settings of 35mm and longer. At the 18mm and 24mm, it fell well within the 'low' band, as shown in the graph below. (The red line delineates the border between 'negligible' and 'low' while the blue line is the border to the 'moderate' zone.)

We detected traces of coloured fringing (mainly green) when test shots were enlarged to 200%. But they would have a negligible impact on everyday photography. Some edge softening can also be seen in the sample image below.

Flare was also handled very well, with little loss of contrast in strong backlighting - although flare spots were found in some test shots, one of which appears below.

The auto white balance setting delivered close-to-neutral colours with fluorescent lights but failed to remove the orange cast of incandescent lighting. However, some reduction of this cast was possible with white balance tuning in the camera and it was easy to remove with editing software and through raw file processing. The tungsten pre-set tended to slight over-correction but we obtained almost neutral colours with the manual measurement function.

The pop-up flash performed as well as the flash on the K10D and K20D models, providing good and even exposures throughout the test camera's ISO range. Long exposures at night were relatively free of colour noise up to ISO 800 but noise had increased slightly at ISO 1600. No stuck pixels were found.

The test camera powered-up almost instantaneously and we measured an average capture lag of 0.2 seconds, which vanished with pre-focusing. Shot-to-shot times averaged 1.2 seconds. In the continuous shooting mode, the test camera recorded four RAW+JPEG images at intervals of 0.8 seconds and took 7.1 seconds to process the burst. Four DNG.RAW files were captured at intervals of 0.4 seconds and processed in just under seven seconds. In the high-speed continuous shooting mode, JPEG files were recorded at 0.35 second intervals and it took 3.8 seconds to process a burst of seven shots.

The test camera's power consumption was relatively high. A set of four AA alkaline batteries was depleted after only195 shots, none of which involved use of the built-in flash.  This is well below the 740 shots/charge offered by the K20D's rechargeable battery.

IMATEST GRAPHS

A typical colour error plot for JPEG files.

A typical coloru error plot for TIFF files resulting from raw file conversions. Note the reduced saturation and relative absence of colour shifts.

Centre-of-field resolution from a JPEG file.

A DNG.RAW file converted in Imatest.

The same DNG.RAW file converted in Adobe Camera Raw.

SAMPLE IMAGES

Auto white balance with incandescent lighting.

Auto white balance with fluorescent lighting.

Close-up.

30-second exposure at ISO 100.

30-second exposure at ISO 1600.

Shot showing the coverage of the kit lens at the 18mm setting...

... and at 55mm.

An example of dynamic range expansion (the shaded areas under the hat brims contain more detail than they would otherwise).

Image sensor: 23.5 x 15.7 mm CCD with 10.7 million photosites  (10.2 megapixels effective)
Lens mount: Pentax KAF2
Focal length crop factor: 1.5x
Image formats: JPEG (3 quality levels), RAW (PEF or DNG); RAW+JPEG supported
Image Sizes: 3872 x 2592, 3008 x 2000, 1824 x 1216
Image Stabilisation: Yes (in body)
Dust removal: SP coating and vibration of optical low pass filter in front of sensor; Dust Alert displays location of dust spots
Shutter speed range: 30-1/4000 second + Bulb
Exposure Compensation: +/- 3EV in ½ EV steps or +/- 2EV in 1/3 EV steps
Self-timer: 2 or 12 second delay
Focus system: TTL phase-matching AF (SAFOX III) with 11 AF area points
Focus modes: AF-S, AF-C, manual focus; adjustable AF point
Exposure metering: 16-segment TTL
Shooting modes: P, Sv, Tv, Av, M, Bulb plus 7 Picture Modes (Auto, Portrait, Landscape, Macro, Moving Object, Night Scene Portrait, Flash Off) and 8 Scene pre-sets (Night Scene, Surf & Snow, Food, Sunset, Kids, Pet, Candlelight, Museum)
Picture Style/Control settings: Image Tone (6 pre-sets), Saturation/Filter Effect, Hue Toning, Contrast, Sharpness
Colour space options: sRGB, Adobe RGB
Custom functions: 23
ISO range: Auto, ISO 100 to 1600 in 1, ½ or 1/3 EV steps
White balance: Auto, Daylight, Shade, Cloudy, Fluorescent Light (x3), Tungsten light, Flash, Manual; fine-tuning available
Flash: P-TTL flash with serial control; GN approx. 13 (ISO 100/m); synch speed at 1/180 sec.; daylight and slow-speed synch
Flash exposure adjustment: -2.0 to +1.0 EV in 1/2EV or 1/3EV increments
Sequence shooting: 2.8 fps/ 4 RAW or JPEG
Storage Media: SD/SDHC memory cards
Viewfinder:  Penta-mirror with Natural-Bright-Matte II focusing screen; approx. 96% field of view; 0.85x magnification; diopter adjustment -2.5 to +1.5 dpt
LCD monitor: 2.7-inch TFT colour display with approx. 230,000 pixels and 160 degree viewing angle
Live View: No
Data LCD: Yes
Playback functions: Single frame, 4/9/16 image index, zoom display (up to 16x, scrolling possible), image comparison, rotating, folder display, slideshow, histogram, bright/dark area alerts
Interface terminals: USB 2.0 Hi-Speed
Power supply: Four AA batteries (alkaline, lithium or NiMH)
Dimensions (wxhxd): 133.5 x 95 x 74 mm (body only)
Weight: 635 grams (with batteries and memory card)