Pentax K10D

Viewfinder (8.75)
The viewfinder is a primary determinant in the shooting experience for most photographers. Comfort, accuracy, and visibility are all critical, since the viewfinder remains flush against the photographer’s face while shooting and is used to compose images.

Previous Pentax DSLRs have supplied adequate viewfinders for the dimensions of the bodies they’re fit into. The K10D, however, is the first to offer a pentaprism, which far exceeds anything we’ve seen from the manufacturer previously. Pentaprisms are rare among sub-$1,000 DSLRs, and offer superior visibility when compared to less expensive – and more prevalent – pentamirror designs.

With 95 percent frame coverage and 0.95x magnification (50mm lens at infinity), the K10D’s viewfinder offers an impressive combination of size and accuracy for its price point. Objects in the window appear nearly as large as they would to the natural eye, and the bright screen shows a discernable "snap" when focusing manually. In terms of framing, the K10D’s viewfinder is about as accurate as its direct competitors. The variance in the composed frame and the captured image was close to uniform in the model we evaluated; we noted just a slight favoring of the left side of the frame.

The rubberized eyecup is centered above the 2.5-inch LCD and protrudes slightly more than 1/8-inch from the viewfinder window. For "left-eyed" shooters, this may be slightly uncomfortable (and unflattering), as the side of their nose and better portion of their cheek will press against the LCD and camera plane. Some eyecups from competing manufacturers are more comfortable. Many Canon cameras, for instance, have a slight angle near the top of the eyecup on both sides that alleviates stress on the user’s eye.

The K10D’s viewfinder window accepts interchangeable focusing screens, enabling users to customize the view for a particular application. The camera ships with a general purpose, "Natural-Bright-Matte II" focusing screen (LF-80 AF Frame Matte), though two accessory options are also available.



Pentax makes an LL-80 AF Divided Matte screen for the K10D, which is described as a "compositional screen." The Divided Matte backdrop displays a 16-cube grid below the AF and metering brackets. The perpendicular lines are particularly useful as a standard by which objects can be vertically and horizontally justified.

The LI-80 Scale Matte screen displays a notched horizontal and vertical line that bisect at the center of the frame, the Scale Matte screen is intended for macro and reproduction work. The ruled lines provide a sense of scope, and also aid in the alignment of objects.

Cut into the top, outer portion of the eyecup is a horizontally-moving dioptric control, with a -2.5m - +1.5m adjustment range. The camera ships with an eyepiece cover to prevent extraneous light from entering and throwing the meter on timed exposures.

Peering through the K10D’s eyecup, the following shooting and camera information is visible:  

AF frame	AF area
Spot metering frame	Spot Metering circle
AF point	AF sensor
Shake Reduction	Visible when shake reduction is engaged
Flash Status	Active when the flash is ready and when recommended, but not in use.
Shutter speed	Option is underlined when setting can be adjusted with the front jog dial
Aperture	Option is underlined when setting can be adjusted with the front jog dial
Focus indicator	Appears when focus has been achieved
Manual focus	Option appears when MF is engaged
EV / Exposure bar	Shows exposure bias; also indicates differences between suggested and selected exposure values
EV compensation	Icon appears when EV comp is in use
Flash EV compensation	Icon appears when flash EV comp is in use or active
AE lock indicator	Visible when AE lock is in use
ISO warning	Appears in eyecup when warning value is Met or exceeded
Number of recordable images	Number of images recordable on the memory card given current picture size options

LCD Screen (6.5)
A 2.5-inch, 210,000-pixel LCD screen sits prominently below the viewfinder on the back of the K10D. The monitor, tagged a "low-temperature wide viewing field poly-silicon TFT color LCD," lags behind its current competitors. DSLR LCDs took a collective leap this year, with most models touting 3-inch displays, composed of 230,000 to 921,000 pixels (though the pixels differ in size).

The K10D also does not supply a full live view like a host of this year’s models (the Canon EOS 40D, Nikon D300, Olympus E-3, and Panasonic L10, among them), though it does offer an interesting compromise. Integrated with the depth-of-field preview control surrounding the shutter release, users can call up a "digital preview" on the LCD screen when activated in the Custom Settings menu. The digital preview presents a fleeting still image of the projected shot using the selected camera settings. The feature gets high marks for innovation and is quite helpful, but may come across to some as a bit clumsy in the context of a now live view-abundant market.

Pentax reports 140-degree angle of view, which seems close to accurate at its extremes. The display refrains from solarization until it reaches the boundaries of its quoted range, but highlights in the image visibly blow out and lose detail when the camera is slightly off axis. This hinders showing images on the screen to a group of people, but shouldn’t pose a problem for examining image details.

Screen brightness levels can be adjusted in the Setup menu. The LCD can be adjusted in 15 steps on a +/- 7 scale.

We found images reproduced on the screen slightly more saturated and contrasty than the captured image, though sharp enough to check focus and subject details.

Monochrome LCD – We appreciate the inclusion of a monochromatic LCD screen on top of the camera. Seemingly elusive on sub-$1,000 DSLRs, informational LCDs are a nice complement to the viewfinder and color LCD display. Placed alongside the shutter release, the monochromatic screen provides an immediate glimpse of settings in near shooting position. This helps facilitate quick adjustments without disrupting workflow.

The following information is visible on the monochromatic screen:

- Shutter speed
- Aperture
- Flash Mode
- Drive Mode 
- Exposure Bar
- EV Compensation
- Auto Bracketing
- Flash Exposure Compensation
- Battery Level
- White Balance
- ISO Warning
- Capture Format
- Number of recordable images
- Multi-exposure

The informational LCD sports a green illuminator light, available by pressing the exposure compensation button.

Flash (6.5)
The Pentax K10D is fitted with a P-TTL pop-up flash with a manual spring release. The flash is released with a dedicated button, located on the left side of the viewfinder hump. Pentax reports a guide number of 11 at ISO 100 (in meters), which is pretty weak, but similar to other manufacturers’ offerings. The max sync speed is 1/180 seconds, limiting fill flash opportunities in bright daylight.

The inclusion of a pop-up flash is convenient, even though the unit itself is not ideal. Users can compensate flash exposures -2.0 - +1.0 EV in 1/2 – or 1/3-stop steps. Unfortunately, the setting is buried in the Function menu and takes significantly more time and fumbling to access than a dedicated control would. To make an adjustment, users have to press the function button and hit the down directional control to access the specified Flash menu. Once in the menu, flash exposure compensation can be adjusted by rotating the rear control dial. The process is cumbersome and seems a bit unnecessary, since the camera includes a dedicated flash button; unfortunately, its sole function is to release the pop-up mechanism.

In our testing, we found the camera’s flash to be acceptable for typical portraits (when compensated), though its limited range and minimal surface area do cast limitations. Similar to most pop-up units, the small flash face produced unappealing hard-edged shadows. The illumination was not uniform, with distinguishable falloff towards the corners at telephoto that only got worse as the focal length was shortened.

Pentax curiously incorporated the autofocus assist illuminator into the flash unit, so it will need to be open to focus in low light, even when attempting to shoot using available light.

The K10D supplies a variety of flash settings; options will depending on exposure mode. The K10D has nine settings: Auto, Flash-off, Flash-On, Red-Eye Reduction, Auto + Red-Eye Reduction, Flash-On + Red-Eye Reduction, Trailing Curtain Sync (Slow), Second-Curtain Slow, and Red-Eye Reduction Slow.

A hot shoe sits atop the viewfinder hump, providing connectivity to dedicated Pentax flashes. The camera does not include a PC terminal to sync with studio strobes. However, there are a number of Hot Shoe-to-PC adaptors compatible with the K10D.

Lens / Lens Mount (8.75)
Refracting light to a 23.5 x 15.7mm CCD sensor (APS-C), lenses applied to the K10D assume a 1.5x conversion factor. Like most current DSLRs, the magnification makes it easier (and less expensive) to attain a telephoto view, though it limits wide angle lens selection to the extreme (20mm and shorter). Users can also seek out digital-specific glass, made to refract light to a cropped sensor, but options are limited.

The K10D carries a KAF2 bayonet mount that accepts KA, KAF, and KAF2 mount lenses. The mount contains an AF coupler, lens information contacts, and K-mount power contacts (power zoom). According to Pentax, the following restrictions are imposed on legacy glass:

S-mount lenses (42mm screw thread mount) - Mount adaptor B is needed to shoot the K10D with an S-mount lens. Once the adaptor is applied, the lens can then be fastened to the camera. S-mount lenses lack the proper connections to communicate with the camera, and have to be adjusted manually on the lens itself.

K Bayonet lenses - K- and M-series lenses attach to the body directly (without the use of an adaptor), but lack the ability to communicate aperture information to the camera. A-series lenses provide automatic aperture control, but can only focus manually.

645 lenses - Manual functionality is available with the application of #38455 Adapter K. Once applied, stop-down metering is required.

67 lenses - Manual functionality is possible with the application of #37954 Adapter B 67. Stop-down metering is also required.

Image Stabilization
The K10D’s CCD sits on a floating mechanism that shifts to compensate for handshake and camera motion. Pentax has branded its system "Shake Reduction (SR)," and claims it surpasses other manufacturers’ efforts because it utilizes a "ball-bearing-mounted oscillator unit" that moves in three directions and grants a wider range of motion. It is advertised to provide an additional two to four stops of shutter latitude. This means a 50mm lens shot at 1/15 seconds with shake reduction will theoretically appear as sharp as an image captured at 1/60 seconds without it. We found this claim to be nearly accurate; 1/15 seconds was possible with a steady hand, and images shot at 1/30 seconds were tack sharp. The system is incredibly useful for low light shooting, and is something we hope all DSLRs will soon include. The K10D's image stabilization system can be turned on or off with a switch on the back of the camera.

Currently, fellow SLR manufacturers Olympus, Sony, and Pentax comrade, Samsung, provide sensor-shift stabilization systems on select DSLR models.

Pentax cautions against using Shake Reduction when panning with moving subjects, indicating it may compensate for motion intentionally included behind the subject. Olympus, on the other hand, implemented a clever mode on its E-3 DSLR, which compensates exclusively along the y-axis. This enables the camera to be moved horizontally and stabilized vertically.

There is no Continuous mode on the K10D’s Shake Reduction system, meaning stabilization occurs only when the shutter is depressed, and no battery power is lost. The K10D also includes an interesting provision to manually input the focal length of older lenses so the camera can apply the proper degree of compensation.