Front Tour Image
Back Tour Image
Sides Tour Image
Top Tour Image
Bottom Tour Image
Box Photo
  • Camera with body cap attached
  • Strap
  • USB cable
  • Camera strap
  • Operating Manual
  • 4 AA disposable lithium batteries

Strangely for a camera with video recording capability, the K-x ships with the cable required to output video to a TV. The required I-AVC7 cable sells for $14.95.

The camera has an approximately 1.5x magnification factor, so the kit 18-55mm lens shoots like a 27-83mm lens on a 35mm camera. The three shots below show the zoom range from widest angle to maximum zoom.

The 23.6 x 15.8mm CMOS sensor has a gross resolution of approximately 12.9 megapixels, and an effective resolution of 12.4 megapixels. The sensor has a dust reducing coating in addition to a sensor shake system. If manual sensor cleaning is required, the Dust Alert feature lets you take a photo of a bright, solid-colored surface and get an image map showing where dust was detected.

The penta-mirror viewfinder is reasonably bright and comfortable, though eyeglass wearers will need to shift the camera a bit to see both the full scene and the information bar at the bottom of the screen. The field of view is approximately 96%, the magnification about 0.85x. The diopter adjustment is a slider at the top of the viewfinder, indented in the eyecup so it won't be moved accidentally. The diopter adjustment range is approximately -2.5 to +1.5m-1.

The illustrations below shows the viewfinder display, first the full screen, then an enlarged view of the information readout.

The LCD is an adequate but uninteresting 2.7-inch 230,000-dot display. LCD brightness can be adjusted along a 15-step scale, with a black-to-gray gradated strip displayed on screen while you move the slider. LCD color can also be adjusted to your liking, though this won't affect the actual color in the photos you shoot.

The illustration below shows the on-screen information display when shooting stills. It may not be the most graphically appealing arrangement, but it's very practical, providing easily legible readings for key shooting settings and readings plus reminders of digital filters and custom image settings in effect (so you're less likely to forget the funky setting you used for a previous shot and ruin the next one), and even at-a-glance reminders of the functions mapped to the four-way controller.

The movie mode info display provides a similar level of detail, including customized image settings along the right side.

Secondary Display

As with most low-cost SLRs, there is no separate monochrome LCD to display shooting settings.

The built-in flash pops up about 3 inches from the center of the lens, a bit close when shooting with a long lens or hoping to avoid red-eye in portraits taken in dark environments. The strobe is quite small, with a very distinct hot spot in the center and relatively narrow coverage. Pentax gives the guide number for the pop-up flash as approximately 16 at ISO 200. Maximum shutter sync speed with the built-in flash is 1/180 second.

Shooting in Auto Picture mode, the flash will pop up automatically be default, but this can be defeated by changing the flash setting, an option too often missing in full auto mode. There is also a separate spot on the mode dial for auto shooting without flash, but this also disables the scene recognition feature ordinarily found in Auto Picture mode.

Pentax has enhanced the settings flexibility of the built-in flash compared to the K2000. Now, in addition to the auto and forced flash mode modes, you can use slow sync for capturing foreground subjects against a dark background, use trailing curtain sync to capture a trailing light effect behind moving subjects, and sync with an external wireless flash unit. Red-eye reduction is available in auto, manual, and slow sync modes.

Flash output compensation is available in a range of -2.0 to +1.0 stops, in 1/3 or 1/2 EV steps.

Shooting with an optional external flash makes P-TTL flash available, which fires a pre-flash to calculate the right exposure for the subject at hand before the photo is actually taken, and should produce a more accurate reading. With the AF540FGZ or AF360FGZ flash units, you can set the sync speed higher than the 1/180 second limit on the built-in flash. Wireless flash control is also available, using the built-in flash or one of the two listed above, along with a compatible external unit.

Flash Photo

The pop-up flash is underwhelming.

There is a single jack, located on the left side of the camera, with a proprietary connection for data and AV output. Unfortunately, the cable required to connect to a TV isn't included in the box, requiring an additional $14.95 purchase (if you can find the I-AVC7 cable at all). This was less of an issue with previous Pentax SLRs, but this one has video recording capability, so output to a TV set is a pretty mainstream activity. Also missing is an HDMI port for connecting to a high-def TV, despite the fact that the K-x does shoot in 720p video mode.

Unlike most SLRs, the Pentax K-x runs on 4 AA batteries (it comes with a set of Energizer Ultimate Lithium AAs).

Pentax claims that without flash you'll get 210 shots with a set of regular alkaline batteries, 1900 shots with pricey lithium disposables, and 640 per charge with rechargeable NiMH (nickel metal hydride) cells. In our initial testing, though, we blew through a set of regular alkalines much faster, and even the expensive lithium disposables didn't come close to 1900 shots. In early December, though, the company introduced a firmware upgrade primarily devoted to addressing just this problem. After upgrading the camera to version 1.01, battery life increased dramatically, approaching the manufacturer's initial claims. That said, we still recommend springing for a set of rechargeable NiMH batteries, since standard alkalines offer limited shooting capacity and the admittedly long-life lithium disposables go for about $15 for a set of four. Radio Shack is currently selling a package with four store-brand NiMH AAs and charger for $30.

Pentax also offers an optional AC adapter kit, K-AC84 ($65), with a battery-shaped coupler that fits in the compartment, which has a notch for the cable when the compartment door is closed.

Battery Photo

The use of AA batteries isn't necessarily a bad thing.

The K-x uses SD/SDHC memory cards, the usual choice for compact digital SLRs.

Memory Photo

SD cards combine high capacity with low price.

As seen in the same-size image crops below, sharpness results are inconsistent, with wide variation based on shooting conditions. This is in part attributable to the extremely small aperture settings available with the kit lens: we expect to see sharpness fall as the lens is stopped down for any camera, and the K-x lens has a minimum aperture of f/40 at its long telephoto setting. More on how we test sharpness.

The K-x incorporates sensor-shift image stabilization in the body of the camera, so any attached lens reaps the benefits (versus Canon and Nikon SLRs, which use lens-based stabilization, with some lenses equipped with IS and others without). And there are benefits to be reaped here, in combatting up-and-down camera shake. When it comes to horizontal camera shake, on the other hand, the IS system was largely ineffective.

We test image stabilization by mounting the camera in a computer-controlled rig that produces programmed movement patterns at low shake levels (about what you'd find in a typical handheld shooting situation) and high shake levels (about the same as shooting one-handed, or while moving). We test at a variety of shutter speeds, moving the camera both horizontally and vertically, with image stabilization turned on and off. The thousands of test photos have their resolution levels analyzed using Imatest software, and the measured differences between results shot with and without IS lets us determine the system's success.

The Pentax K-x was less accurate in its color reproduction than most cameras we test. To determine color accuracy, we shoot the X-Rite ColorChecker chart under bright studio lighting, in each available color mode, and analyze the resulting images using Imatest software to measure the color deviation from the known chart values. The score is based on the result for the most accurate color mode.

The K-x offers six color mode choices, the most accurate of which is called Natural. This is the only available choice that's properly saturated, at 103.5%, The next closest to ideal, Bright mode, is oversaturated to 123%. While it's not unnaturally vivid, even the Natural mode exhibits substantial color shifts, most notably when reproducing orange and yellow shades. Blue, red and magenta, though, are reproduced quite accurately. Flesh tones are off a bit, but it will take a critical eye to notice this shift. More on how we test color.

NOTE: Because of the way computer monitors reproduce colors, the images above do not exactly match the originals found on the chart or in the captured images. The chart should be used to judge the relative color shift, not the absolute captured colors.

The default color accuracy for the K-x in its best mode is less precise than the other cameras in our line-up. Color shifts are most noticeable for orange and yellow, which fortunately aren't that prominent in most photos.

The K-x offers seven Custom Image settings, which control color along with saturation, hue, brightness, contrast and sharpness, all of which can be adjusted. Six of these settings are in color: Bright, Natural, Portrait, Landscape, Vibrant and Muted. The final choice is monochrome. For more information and image samples comparing Custom Image settings, see the Picture Effects section.

In the table below are same-size crops from our test images for five of the color modes. You'll find samples taken in Muted and Monochrome modes in the Picture Effects section of this review.

The K-x is a mediocre performer in white balance adjustment accuracy, lagging the competition using the automatic white balance system and falling short of the color accuracy levels we expect after taking a manual white balance reading.

We check white balance performance by shooting the X-Rite ColorChecker chart under daylight, incandescent and compact fluorescent lighting produced using the X-Rite Judge II light box. The test photos are analyzed using Imatest software, with color error measurements compared against the known values of the ColorChecker chart.

Automatic White Balance ()

The automatic white balance system handles daylight illumination well, but it's flummoxed by compact fluorescent and incandescent lighting, like that produced by household tungsten bulbs.

Custom White Balance ()

We demand a very high level of color accuracy after going to the trouble to take a custom white balance reading with an SLR. The K-x didn't live up to these standards, Shots taken under incandescent lighting were much improved compared to the automatic WB results, but still no great shakes compared to other tested cameras.

The K-x couldn't match the exemplary results delivered by the K2000 in daylight shooting, but its WB accuracy holds up well compared to the other tested cameras.

Incandescent illumination is consistently the most challenging light source for automatic white balance systems, and the K-x is not alone in failing to cope well. The GF1 was the noteworthy exception to the orange-tinged rule here.

The Pentax K-x handled compact white fluorescent lighting poorly compared to the competition, including the exceptional K2000 results.

Overall, the Pentax K-x offers underwhelming white balance accuracy levels.

The K-x provides a generous selection of white balance presets, including a variety of fluorescent bulb types.

The on-screen preview system works well when setting white balance. By pressing the exposure compensation button, you capture a preview image at current settings. Then, as you cursor through your white balance preset options, or fine-tune the setting along the green-magenta and/or blue-amber axes, you see the effects of your changes live on the preview image (which you can save as well, if the spirit moves you).

Taking a manual white balance reading is simple enough. You shoot a white or neutral gray surface under current lighting conditions. You can then make the selection area larger or smaller, and move it around the screen, to specify the precise area you want to use for taking a reading.

Our long exposure testing combines color accuracy and image noise analysis at slow shutter speeds (between 1 and 30 seconds), at low light levels. The K-x didn't fare badly in the noise component, but its bright light color problems carried over when the lights were low, leading to a mediocre overall score. More on how we test long exposure.

The good news is that the color didn't shift when the shutter speed changed — consistency here is a virtue — and there was only slight oversaturation. However, the color hues weren't reproduced accurately, leading to a low score here. As expected, results were very close whether long exposure noise reduction was turned on or off.

Image noise results aren't great, but at under 1% across the shutter speed range the images are certainly useable. As we often find, long exposure noise reduction had no positive effect, and doubled the elapsed time for each shot. Long exposure noise reduction systems work by taking a second exposure with the shutter closed, determining the noise pattern in that shot and mathematically removing these flaws from the original. However, since most image noise is unpredictably random from shot to shot, the system rarely works and, in fact, often increases visible noise.

The Panasonic GF1, with its noisy Micro Four Thirds sensor, posted a slightly lower score than the Pentax K-x, but all of the other comparison cameras (including the non-video Pentax K2000 model) posted higher scores in our long exposure test.

We used the default configuration for high ISO noise reduction in our testing, but the K-x offers some flexibility here. By default, high ISO noise reduction kicks in after ISO 800. However, through a custom menu setting, you can choose the setting to start applying noise reduction.

The noise reduction processing does have a significant impact, cutting visible noise by nearly half at ISO 1600.

We break down overall image noise into its component parts, red, blue, green, yellow and chroma (gray). If noise in one color channel is considerably higher than the others it can make noise visibility worse, but that's not the case here. More on how we test noise.

Available standard ISOs range from 200-6400, with an expanded ISO range from 100-12800. There's an Auto ISO mode, which allows the user to limit the highest acceptable setting anywhere from ISO 200-12800.

The K-x performed well in our dynamic range testing, making it a good choice for handling high-contrast shooting situations without losing detail in the very bright or deeply shadowed areas. We test dynamic range by shooting a Kodak stepchart with 20 patches from solid white to solid black, with a range of gray values in between. Test photos are taken at each ISO level, across the full aperture range. These test images are then analyzed using Imatest software to determine how many distinct patches can be identified in each, then those results are compiled to create an overall picture of the camera's performance.

The K-x delivers a 7-stop dynamic range at ISO 200, which is quite good, and retains nearly 5 stops out to ISO 1600. More on how we test dynamic range.

Comparing dynamic range for the cameras in our roundup at ISO 200, only the Canon T1i offered a wider dynamic range. After that, though, the T1i takes a steep dive, down to 4.27 stops at ISO 400, at which point the K-x still measures 6.21 stops.

We used the default configuration for high ISO noise reduction in our testing, but the K-x offers some flexibility here. By default, high ISO noise reduction kicks in after ISO 800. However, through a custom menu setting, you can choose the setting to start applying noise reduction.

The noise reduction processing does have a significant impact, cutting visible noise by nearly half at ISO 1600.

We break down overall image noise into its component parts, red, blue, green, yellow and chroma (gray). If noise in one color channel is considerably higher than the others it can make noise visibility worse, but that's not the case here. More on how we test noise.

Available standard ISOs range from 200-6400, with an expanded ISO range from 100-12800. There's an Auto ISO mode, which allows the user to limit the highest acceptable setting anywhere from ISO 200-12800.

The K-x incorporates a significant autofocus system improvement over the K2000 introduced earlier this year. The camera now uses 11 autofocus points (versus 5 for the K2000) and offers four AF point selection modes: the camera can choose from 5 or 11 points, the user can select one of 11 points manually, or the center point can be set in spot mode.

Autofocus speed isn't lightning-fast, but it's not bad — certainly up to the task for day-to-day shooting, and even sports photography works reasonably well, particularly when using continuous focus mode.

If you're trying to snag a sharp shot of a moving subject, catch-in focus is available. You set the focus on a point that the subject will pass and hold the shutter button halfway. When your quarry appears and is in focus, the shutter trips automatically.

The camera doesn't have a dedicated autofocus assist lamp, relying instead on a brief burst of light from the pop-up flash to help achieve focus in dark environments. Fortunately, the system works quickly enough in most low-light conditions even without the flash assist, so you'll be able to take your indoor candids without being branded a flasher.

Our long exposure testing combines color accuracy and image noise analysis at slow shutter speeds (between 1 and 30 seconds), at low light levels. The K-x didn't fare badly in the noise component, but its bright light color problems carried over when the lights were low, leading to a mediocre overall score. More on how we test long exposure.

The good news is that the color didn't shift when the shutter speed changed — consistency here is a virtue — and there was only slight oversaturation. However, the color hues weren't reproduced accurately, leading to a low score here. As expected, results were very close whether long exposure noise reduction was turned on or off.

Image noise results aren't great, but at under 1% across the shutter speed range the images are certainly useable. As we often find, long exposure noise reduction had no positive effect, and doubled the elapsed time for each shot. Long exposure noise reduction systems work by taking a second exposure with the shutter closed, determining the noise pattern in that shot and mathematically removing these flaws from the original. However, since most image noise is unpredictably random from shot to shot, the system rarely works and, in fact, often increases visible noise.

The Panasonic GF1, with its noisy Micro Four Thirds sensor, posted a slightly lower score than the Pentax K-x, but all of the other comparison cameras (including the non-video Pentax K2000 model) posted higher scores in our long exposure test.

Testing the Pentax K-x with its kit lens, the camera didn't do a very good job with low light sensitivity. Still, compared to some of the abysmal results we've gotten from other video-capable DSLRs, the K-x's numbers don't look too bad. The K-x required 23 lux of light to register 50 IRE on our waveform monitor. Of the DSLRs we compared it to below, only the Nikon D5000 had a better low light sensitivity (the Panasonic GF1 and Canon T1i were just slightly worse than the K-x).

There wasn't much chromatic aberration at most settings, though a keen eye will note some problems when shooting at the widest zoom..

The K-x offers optional digital processing to control lateral chromatic aberration adjustment.

The K-x delivers nice results at the widest lens setting, with softness and chromatic aberration becoming a bit more noticeable with the aperture stopped down to f/22, but still not bad.

Images shot at the middle aperture setting look crisp, while both extremes show some softness, though little chromatic aberration.

Shooting at the highest zoom setting under bright studio lighting, we again see far superior results in the middle aperture range than at the larger or smaller ends of the spectrum.

We don't include distortion results in our scoring for cameras with interchangeable lenses, but we do run the test on the kit lens. In this case, there was virtually no distortion when shooting in the middle of the zoom range, some slight pincushioning at full telephoto and quite a bit of barrel distortion (over 2.5%) at the widest angle 18mm setting (equivalent to 27mm on a 35mm camera).

The K-x has an optional distortion correction system that attempts to digitally manipulate an image to minimize the effect of distortion when shooting with a compatible lens.

The Pentax K-x can only record video with a 24p frame rate, although it has both HD (1280 x 720) and SD (640 x 480) recording options. The videos shown below have been heavily compressed during the upload process to YouTube, but they should still give you an idea about how well each camera captures motion video. More on how CamcorderInfo tests motion.

The Pentax K-x showed very little artifacting in our motion test, but its video wasn't that smooth. The camera appeared to render somewhat jerky motion, especially when compared to the kind of motion produced by a traditional camcorder. Still, the fact that the K-x had such low amounts of artifacting is definitely a plus.

The Nikon D5000 wasn't very good in our motion test. Its 24p footage had a lot of artifacting and frequency interference. We noticed jagged lines (like lightning bolts) on our black and white pinwheel, as well as some blur on our RGB pinwheel. The camera simply couldn't render motion that looked good in our testing.

The GF1 has a couple of different recording options for HD video—a 60p mode and a 30p mode. We had a good deal of trouble dealing with the GF1's 60p setting when we imported the footage onto our computer (the videos played back at double speed), but we chalked this up to a compatibility issue with Panasonic's AVCHD Lite compression system. Shooting with the GF1's 30p mode, which uses MJPEG compression, we saw some artifacting, pixelation, and choppy video, but we were able to import the files to our computer with no problems.

The Canon T1i did produce fairly artifact-free video in our motion test, but the camera was marred by its unusual 20p frame rate when shooting 1920 x 1080 video. The footage looked awkward and choppy due to the low frame rate, and for this reason we recommend the Canon 7D instead. The 7D offers similar video performance to the T1i, but includes more popular 24p and 30p frame rates instead. The Canon T1i does, however, include a 720/30p setting that showed some better results in our motion test.

The Pentax K-x appeared to deliver a sharper image than most video-DSLRs that record 720p video. According to our measurements, the camcorder managed a horizontal sharpness of 650 lw/ph and a vertical sharpness of 600 lw/ph. These numbers are slightly better than the Nikon D5000 and Panasonic GF1 put up, but most of the DSLRs with 1080p capability had better sharpness numbers (because they shoot video at a higher resolution).

The problem with the K-x when it comes to video sharpness is the fact that the camera has no HDMI output. You can only output video on the camera using the proprietary AV-out port (that also doubles as a USB port) on the left side of the camera. This means you're viewing the 1280 x 720 HD video through a low-quality analog connection when you connect the K-x to a television—so you're really losing all that HD quality and sharpness when you watch videos this way. You can import the footage to your computer and watch it in HD there, however, but we're guessing you'd rather watch HD video on a large HDTV if given the option. More on how CamcorderInfo tests video sharpness.

Testing the Pentax K-x with its kit lens, the camera didn't do a very good job with low light sensitivity. Still, compared to some of the abysmal results we've gotten from other video-capable DSLRs, the K-x's numbers don't look too bad. The K-x required 23 lux of light to register 50 IRE on our waveform monitor. Of the DSLRs we compared it to below, only the Nikon D5000 had a better low light sensitivity (the Panasonic GF1 and Canon T1i were just slightly worse than the K-x).

The K-x provides direct access buttons for the most frequently used shooting adjustments — ISO, white balance, drive mode and flash control — and the comprehensive quick menu (available by pressing the Info button) displays nearly all the settings on a single screen. The layout will look familiar to anyone who's checked out the Pentax K2000, which is nearly identical. To accommodate Live View access (the K2000 lacks this feature), Pentax added a dedicated button in place of the delete button. The delete function now shares the flash pop-up button, which works out fine.

As with most SLRs today, the K-x offers both a traditional full menu system and a quick menu (which Pentax calls the control panel) providing ready access to the most frequently changed shooting settings. The control panel is accessed by pressing the INFO button in shooting mode, which toggles between the LCD info display, the control panel and turning the LCD off entirely.

To change settings in the control panel, you move the cursor to the relevant category using the four-way controller, At that point you can turn the control dial to cycle through settings, or press OK and bring up a menu displaying all the available options. The settings with dedicated buttons on the camera body aren't included in the control panel.

The main menu system is broken into four sections: record, playback, setup and custom. All but the playback section have multiple screens, but turning the e-dial makes them easy to navigate — unlike some menu systems, you don't have to cursor up to the top of a list to move to the next screen of options. We also like the fact that all of your choices are visible on screen at once, without having to scroll down to the bottom of a column to reveal hidden options below.

The white-on-gray text is perfectly legible. And while the quick menu uses icons to fit as many options as possible in a confined space, the main menu system writes out each option clearly. Some commands are placed in categories we found unintuitive; noise reduction choices are found in the custom menu rather than record, while the programmable green button functions are assigned via the record menu. It didn't take us long to get used to the few oddities, though.

In a feature we've applauded in Pentax point-and-shoots, the K-x lets you easily choose which camera settings will be retained and which will be reset when you turn the camera off and turn it back on. There's a checkbox listing in the fourth Record Mode menu that includes settings for flash mode, drive mode, white balance, ISO, EV and flash compensation, cross processing, digital filter, HDR capture, shooting info display, playback info display and file numbering.

The 320-page Operating Manual generally does a good job of explaining the camera's broad and deep feature set. The writing is clear, and the illustrations, charts and diagrams well designed. Pentax also deserves praised for providing a detailed index that's genuinely useful, plus a glossary that explains concepts like RAW format, color temperature and histograms. There's an unfortunately intimidating information dump at the very beginning of the manual, before you get to the Getting Started section, and unlike the Pentax K2000, there's no separate software user manual, leaving you to learn a complex program using the software help system. We found only one factual error: the procedure described in the section on Readjusting Images Shot in JPEG Format doesn't work, and it took quite some time with tech support (via live online chat) to sort it out. Overall, though, this is a solid effort. To see for yourself, download a copy in PDF format from the Pentax web site here.

At 4.8 x 3.5 x 2.7 inches (122 x 91 x 67mm) and 18.2 oz. (515g), the Pentax K-x is a compact SLR, but one that feels solid and substantial in your hands. The right grip is a bit short and narrow if you have large hands, but it does have a rubberized coating to prevent slippage, an unusual feature in an inexpensive camera. The thumb rest on the back has a deep curved shape that works well to balance the camera's weight, though it would be better with a more textured surface.

The buttons and the control dial are positioned nicely; there's virtually no chance you'll change a setting accidentally. With the playback button at the top of the four-button lineup and the menu button at the bottom, these frequently used controls can be accessed quickly, without searching. And the control wheel, just to the left of the thumb rest, clicks distinctly to provide feedback as you make adjustments. All in all, a successful design for a small camera body.

Handling Photo 1

The K-x body is compact but comfortable, with a well-designed grip.

Handling Photo 2

The K-x provides direct access buttons for the most frequently used shooting adjustments — ISO, white balance, drive mode and flash control — and the comprehensive quick menu (available by pressing the Info button) displays nearly all the settings on a single screen. The layout will look familiar to anyone who's checked out the Pentax K2000, which is nearly identical. To accommodate Live View access (the K2000 lacks this feature), Pentax added a dedicated button in place of the delete button. The delete function now shares the flash pop-up button, which works out fine.

Buttons Photo 1
Buttons Photo 2

The LCD is an adequate but uninteresting 2.7-inch 230,000-dot display. LCD brightness can be adjusted along a 15-step scale, with a black-to-gray gradated strip displayed on screen while you move the slider. LCD color can also be adjusted to your liking, though this won't affect the actual color in the photos you shoot.

The illustration below shows the on-screen information display when shooting stills. It may not be the most graphically appealing arrangement, but it's very practical, providing easily legible readings for key shooting settings and readings plus reminders of digital filters and custom image settings in effect (so you're less likely to forget the funky setting you used for a previous shot and ruin the next one), and even at-a-glance reminders of the functions mapped to the four-way controller.

The movie mode info display provides a similar level of detail, including customized image settings along the right side.

Secondary Display

As with most low-cost SLRs, there is no separate monochrome LCD to display shooting settings.

The penta-mirror viewfinder is reasonably bright and comfortable, though eyeglass wearers will need to shift the camera a bit to see both the full scene and the information bar at the bottom of the screen. The field of view is approximately 96%, the magnification about 0.85x. The diopter adjustment is a slider at the top of the viewfinder, indented in the eyecup so it won't be moved accidentally. The diopter adjustment range is approximately -2.5 to +1.5m-1.

The illustrations below shows the viewfinder display, first the full screen, then an enlarged view of the information readout.

The K-x incorporates sensor-shift image stabilization in the body of the camera, so any attached lens reaps the benefits (versus Canon and Nikon SLRs, which use lens-based stabilization, with some lenses equipped with IS and others without). And there are benefits to be reaped here, in combatting up-and-down camera shake. When it comes to horizontal camera shake, on the other hand, the IS system was largely ineffective.

We test image stabilization by mounting the camera in a computer-controlled rig that produces programmed movement patterns at low shake levels (about what you'd find in a typical handheld shooting situation) and high shake levels (about the same as shooting one-handed, or while moving). We test at a variety of shutter speeds, moving the camera both horizontally and vertically, with image stabilization turned on and off. The thousands of test photos have their resolution levels analyzed using Imatest software, and the measured differences between results shot with and without IS lets us determine the system's success.

The K-x offers a fully automatic shooting mode that attempts to use scene recognition and set the camera accordingly. We like this approach, and found that the system usually made an appropriate choice. Among the other shooting modes, the only oddball is Sv (for sensitivity value), which adjusts the aperture and shutter speed based on changes to the ISO setting.

The K-x incorporates a significant autofocus system improvement over the K2000 introduced earlier this year. The camera now uses 11 autofocus points (versus 5 for the K2000) and offers four AF point selection modes: the camera can choose from 5 or 11 points, the user can select one of 11 points manually, or the center point can be set in spot mode.

Autofocus speed isn't lightning-fast, but it's not bad — certainly up to the task for day-to-day shooting, and even sports photography works reasonably well, particularly when using continuous focus mode.

If you're trying to snag a sharp shot of a moving subject, catch-in focus is available. You set the focus on a point that the subject will pass and hold the shutter button halfway. When your quarry appears and is in focus, the shutter trips automatically.

The camera doesn't have a dedicated autofocus assist lamp, relying instead on a brief burst of light from the pop-up flash to help achieve focus in dark environments. Fortunately, the system works quickly enough in most low-light conditions even without the flash assist, so you'll be able to take your indoor candids without being branded a flasher.

When focusing manually, the viewfinder focus confirmation indicator lights when the subject comes into focus. However, the focus ring on the kit lens has very little friction, making manual focusing a chore, and hitting the precise point where that indicator light blinks on is awfully tricky.

The K-x supports four resolution settings. There are three available JPEG compression settings. In both RAW and RAW+JPEG modes, shooting is supported in Pentax's PEF format or the DNG format created by Adobe. One of the many options for the programmable Green Button is switching temporarily to RAW+JPEG mode.

Post-Shot Image Adjustment

This is an innovative idea we don't remember seeing before. Say you shoot a JPEG image and realize you should have used a different white balance setting, As long as you haven't taken another shot, you can press the left-most button on the four-way controller and bring up the white balance setting screen. You can then change the white balance setting, while viewing an on-screen playback of the photo you just shot, and save an alternative image based on the original uncompressed data stored in the buffer, avoiding any image quality deterioration that ordinarily occurs when editing JPEGs. You can also change the custom image setting in the same way, based on uncompressed data, though the procedure for doing this described in the manual is entirely incorrect. Instead of pressing the right four-way controller button as specified, you have to bring up the quick menu system and choose Custom Image to make the adjustment.

Copyright and Photographer Info

Copyright and photographer name information can be automatically stored in the EXIF data with an image.

There are two settings for continuous shooting, Hi promises 4.7 shots per second up to 17 frames in a row, and came very close. There's also Lo, which shoots at about 2 frames per second, but can continue at that rate until you've filled up the SD card. RAW shooting is also speedy, but you can only shoot 5 shots continuously in high-speed mode before giving the buffer time to clear.

Pentax promises a high burst rate of approximately 4.7 fps, and our testing proved they're not far off the mark. Shooting full-resolution, large JPEGs, we clocked the camera at 4.22 shots per second, the fastest speed in our comparison group.

There are two self-timer modes: 2 second and 12 second. An optional wireless remote control is available, which can be used to trigger the shutter immediately or after a 3-second delay.

The K-x incorporates a significant autofocus system improvement over the K2000 introduced earlier this year. The camera now uses 11 autofocus points (versus 5 for the K2000) and offers four AF point selection modes: the camera can choose from 5 or 11 points, the user can select one of 11 points manually, or the center point can be set in spot mode.

Autofocus speed isn't lightning-fast, but it's not bad — certainly up to the task for day-to-day shooting, and even sports photography works reasonably well, particularly when using continuous focus mode.

If you're trying to snag a sharp shot of a moving subject, catch-in focus is available. You set the focus on a point that the subject will pass and hold the shutter button halfway. When your quarry appears and is in focus, the shutter trips automatically.

The camera doesn't have a dedicated autofocus assist lamp, relying instead on a brief burst of light from the pop-up flash to help achieve focus in dark environments. Fortunately, the system works quickly enough in most low-light conditions even without the flash assist, so you'll be able to take your indoor candids without being branded a flasher.

When focusing manually, the viewfinder focus confirmation indicator lights when the subject comes into focus. However, the focus ring on the kit lens has very little friction, making manual focusing a chore, and hitting the precise point where that indicator light blinks on is awfully tricky.

The Pentax K-x records video using the Motion JPEG (MJPEG) compression. This is the same system used by the Nikon D5000, as well as a number of point-and-shoot digital cameras that offer video modes. MJPEG is a common compression system, so compatibility with your media player or editing software shouldn't be an issue. Motion JPEG isn't very efficient, however, and it isn't regarded as the highest-quality compression system for HD video. The MJPEG video files recorded on the Pentax K-x are saved as AVI files.

There aren't too many format options for recording video on the K-x. There's a single HD recording setting, which captures 1280 x 720 video with a 24p frame rate, and there's a standard definition option that records with a 640 x 480 resolution (also at 24p). The camera offers three unnamed quality settings for video recording, each of which is represented by a series of stars in the menu. We assume these quality settings each use different bitrates because you can record more video with the one-star setting than you can with the three-star setting — but Pentax doesn't list any specs or bitrates when referring to the quality options. Pentax simply calls the quality settings Best (three starts), Better (two stars), and Good (one star). Find out how the performed in our video image quality test./r:link_to_content

Auto Controls

Since the K-x has no continual autofocus feature we can't really give its auto controls a full recommendation. If you want to focus while recording video you must do so manually (by rotating the lens ring), and if you want to use autofocus you have to press the shutter button halfway before recording (just like you do to take a still photo).

The camera's other auto controls aren't bad. Auto white balance generally worked well in video mode, but it wasn't perfect in all kinds of light. The camera offers plenty of white balance presets, however, so you shouldn't have any trouble fine-tuning the color temperature to your preference. Auto exposure adjustments were very slow, but the system worked smoothly when we moved from light to dark scenes. Some users may like the slow transition of exposure (it almost looks like you are rotating a dial manually), while those used to the snap-like exposure offered on many consumer camcorders will probably be disappointed.

Zoom

Zoom is controlled on the K-x by rotating the large lens ring on the attached lens. The quality and feel of this ring will be different depending on what lens you have connected to the camera—as will the zoom ratio. The kit lens with the Pentax K-x is an 18 - 55mm lens, which is close to a 3x zoom. You can zoom while recording video with the K-x, but you must do so by rotating the lens ring.

Focus

The K-x has no continual autofocus feature, which means the only way to keep a moving subject in focus while you record is to do so manually by rotating the focus ring. This is an issue that plagues many video-capable DSLRs, with the notable exception of the Micro Four Thirds models from Panasonic and Olympus.

In addition to not offering a live autofocus feature, the K-x also has one of the loudest and slowest autofocus mechanisms of any video-capable DSLR we've tested. The camera's live view mode must go blank for a moment while the camera performs an autofocus (which is done by pressing the shutter halfway or by pressing the AF button), and you cannot perform any kind of autofocus while recording is taking place.

Exposure Controls

The K-x isn't loaded with manual controls in video mode, but adjustments to exposure and aperture can be made (shutter speed can't be controlled manually). There are 13 increments of basic exposure control on the K-x, ranging from -2 to +2 in 1/3 EV steps. Adjusting exposure is quite simple, but it cannot be performed while recording is taking place. When you set a manual exposure prior to recording, however, this exposure is locked for the duration of the clip (auto exposure is turned off).

To set aperture manually in video mode you must go into the camera's menu and switch aperture from auto to fixed. The camera offers plenty of aperture values, ranging from f/3.5 to f/40, but you have to start recording before you can see what kind of exposure level your manual aperture is going to give you. To compensate for this, the aperture selection will blink in red if there isn't enough light to use it. You can still use these aperture settings, but your recorded image will likely be too dark.

Other Controls

As with shutter speed, ISO cannot be set manually on the K-x. You can set white balance manually, but you must leave video mode to do so. You can then put the camera back into video mode (with a manual white balance selected) and use your manual white balance. We're kind of annoyed by this roundabout system, but quirks like this are rather common on video-capable DSLRs.

There is also an image stabilization feature that can be turned on and off in video mode, but it makes loud, consistent noises while engaged. We recommend turning the stabilization feature off if you are at all concerned about picking up unwanted noises on the K-x's built-in microphone (the crackling sound created by the stabilization system can also be very annoying to listen to for extended periods of time). Still, the built-in mic on the K-x is not very good to begin with, so if you care about audio you shouldn't be using it to record sound in the first place.

The audio features on the Pentax K-x are the epitome of 'bare-bones.' All the camera has is a tiny monaural microphone on its upper left side. The mic isn't well placed, as it's positioned right in the spot where you might end up resting your fingers if you don't like holding the lens while you shoot. The Pentax K-x picks up tons of operating noise with its built-in mic, but this is something we've seen from most video-capable DSLRs. When using the built-in mic, expect to hear plenty of noise from the autofocus motor, lens and dial movement, and image stabilization system (if it is turned on).

The group of video-DSLRs listed in the table below are all sub par models when it comes to audio features. None of them have external microphone inputs, and each of them lack any special audio controls — except for the GF1, which has a mildly useful wind cut option. The point is, if you need quality audio with any of these cameras you're going to have to record to a separate audio device entirely.

Box Photo
  • Camera with body cap attached
  • Strap
  • USB cable
  • Camera strap
  • Operating Manual
  • 4 AA disposable lithium batteries

Strangely for a camera with video recording capability, the K-x ships with the cable required to output video to a TV. The required I-AVC7 cable sells for $14.95.

Meet the tester

Steve Morgenstern

Steve Morgenstern

Editor

Steve Morgenstern is a valued contributor to the Reviewed.com family of sites.

See all of Steve Morgenstern's reviews

Checking our work.

We use standardized and scientific testing methods to scrutinize every product and provide you with objectively accurate results. If you’ve found different results in your own research, email us and we’ll compare notes. If it looks substantial, we’ll gladly re-test a product to try and reproduce these results. After all, peer reviews are a critical part of any scientific process.

Shoot us an email