Pentax K-7 Review

June 24, 2009 | Mark Goldstein |


The Pentax K-7 is one of the more exciting new DSLR cameras of 2009, signalling Pentax's entry into the super-competitive semi-pro category. Going up against the likes of the Canon EOS 50D and Nikon D300, the 14.6 megapixel K7 certainly has a lot to offer on paper, surpassing its main rivals in many ways. The Pentax K-7 joins the growing list of DSLR cameras that can record video, with a best quality setting of 1536x1024 pixels at 30fps. In-camera High Dynamic Range is another up-to-the-minute feature, combining three differently exposed images on-the-fly to create a single photo with expanded dynamic range. Autofocus, traditionally one of the weaker points of Pentax SLRs, has been significantly upgraded to a new 11-point wide-frame AF module with 9 cross sensors and 2 line sensors. The dust-, weather- and freeze-proof Pentax K-7 has 77 weather / dustproof seals, a stainless-steel alloy chassis, a shutter designed for 100,000 releases, a top shutter speed of 1/8000th second, a through-the-lens optical viewfinder with 100% frame coverage and 0.92x magnification, and a new 77-segment matrix meter. With barely a pause for breath, the K7 boasts a high-resolution 3-inch LCD monitor with 920k dots, built-in dust removal and shake-reduction systems, continuous shooting rate of 5.2fps, improved Live View with Face Recognition AF, and automatic compensation of lens distortion and lateral chromatic aberrations with DA and DFA lenses. In the UK the Pentax K-7 costs £1199.99 body only, £1229.99 with the 18-55mm kit lens, and £1329.99 with the 18-55mm + 50-200mm double kit lens. In the US, the K-7 body only costs $1299.95 and the new lenses are priced at $199.95 for the 18-55mm and $249.95 for the 50-200mm.

Ease of Use

The Pentax K-7 is a little smaller - 96.5(H) x 130.5(W) x 72.5(D) - and a little lighter - 670g without the battery or memory card fitted - than the older K20D model, but in many respects the two cameras share a very similar external design. As soon as you pick the K-7 up, you can instantly tell that it's a serious camera, feeling more solid than its main rivals, the Canon EOS 50D and Nikon D300, despite being quite a lot smaller than them. This is mainly due to the K-7's stainless-steel alloy frame and lightweight magnesium-steel alloy body, which is a world away from Pentax's much smaller and lighter entry-level DSLR cameras, signifying the company's attempt to provide a DSLR that will appeal to more experienced photographers. The K-7 is dust, cold and water resistant, thanks to a system of 77 special seals used throughout the design, and it can operate at temperatures as low as -10°C. This shows itself most obviously via the battery compartment and the memory card slot. The former is opened via a small rotating latch, which is reassuring but a little fiddly to use if you're in a hurry though.

The K-7 features a newly designed shutter unit which provides a fast top shutter speed of 1/8000th second and a very competitive 100,000 shutter release life-span, a figure more commonly associated with professional SLR cameras. One of our main criticisms of the K20D kit has been addressed with the introduction of a new standard 18-55mm kit lens that's better built and more weather-proof than its predecessor. The smc PENTAX-DA 18-55mm F3.5-5.6AL WR lens features a newly designed, simplified weather-resistant construction designed to minimise the intrusion of water and moisture into the lens barrel. There's also a special coating which repels dust, water and grease and makes it easy to wipe off fingerprints and cosmetics. Consequently it feels much more at home on the K-7 than the previous 18-55mm kit lens did on the K20D, although it remains a rather slow lens at both ends of the focal length (f3.5-5.6).

As it's aimed at the more experienced digital SLR owner, the K-7 is a complex camera in terms of functionality and the number of external controls that it offers, with over 25 in total and a lot of them having more than one function. Despite the presence of so many buttons and switches, the Pentax K-7 doesn't feel too cluttered or intimidating, although it will certainly take some time to adapt to for people moving up from an entry-level SLR. Departing from the recent trend of ultra-compact SLR models, the K-7 is definitely designed for "normal" hands. The camera has a deep, contoured handgrip on the right-hand side, coated in a rubberized compound to aid grip, that enabled me to use three fingers to hold it and my right forefinger to operate the shutter button. There is a generous contoured area where your right thumb sits, with the rest of the body finished in a textured matt black. The shutter release action on the Pentax K-7 is quieter than on the K20D but still quite loud and mechanical, something that you will either love or hate. I liked it, although it isn't great for close-up candid photography as your subject will probably hear you if you get too close.

On the front of the camera body is the RAW button, which instantly sets the image quality to whichever RAW format is selected in the menu system (either Pentax's PEF format or Adobe DNG), useful if you are shooting in JPEG and want to quickly switch to RAW mode for a particular image. Located underneath is the Autofocus Mode switch, with three available modes, and above a small button for opening the pop-up flash, which extends quite high above the lens to help minimise red-eye. On the bottom of the K-7 is the weather-sealed battery compartment, housing a rechargeable 1860mAh D-LI90 lithium-ion battery. The camera managed over 750 shots using the supplied rechargeable Li-ion battery before being depleted, a significant improvement on the older K20D. There's also a metal tripod mount that's perfectly in-line with the centre of the lens mount.

On the right-hand side of the K-7 is the weather-sealed SD / SDHC memory card slot, and located below is the remote cable release connector. On the left-hand side is a large vertical flap covering the DC In, AV Out and HDMI connectors. The HDMI port allows you to connect the K-7 to a high-def TV set, but only if you purchase an optional HDMI mini-cable. Above this is a small Mic port for connecting an external microphone, protected by a round rubber seal that refused to stay in place.

Pentax K-7 Pentax K-7
Front Rear

The Pentax K-7 follows conventional DSLR design in having a shooting mode dial on the top-left of the camera, which allows you to select either one of the advanced mode like Aperture-priority, Shutter-Priority and Manual, or the more point-and-shoot Auto and Program modes. There are no scene modes on this camera, signaling its intent as a serious photographic tool. You'll instantly notice that the K-7 has a couple of unusual shooting modes that you won't have seen before on any other camera (apart from the older K10D and K20D models). These are the Sensitivity-Priority and Shutter & Aperture-Priority modes, and they are genuinely useful additions.

Sensitivity-Priority automatically selects the best combination of aperture and shutter speed for your chosen ISO speed. The sensitivity can be shifted instantly (in 1/2 or 1/3 steps) by turning the rear control dial. This allows you to quickly select an ISO speed, without having to access the menu system, which is very useful in rapidly changing light conditions. In Shutter & Aperture-Priority mode the camera selects the most appropriate ISO speed for a shutter speed and aperture combination, allowing you to use ISO sensitivity as a third factor in determining the correct exposure. As digital cameras have always offered the unique ability to instantly change the sensitivity, it's surprising that Pentax are still the only manufacturer to allow you to use ISO in this way. At the base of the shooting mode dial is a switch which selects from one of the three metering modes - multi-segment, centre-weighted or spot - which all use the new 77-segment multi-pattern metering system.

On the right hand side of the top of the K-7 is the small shutter button, surrounded by the on/off switch. This has a third setting, which by default activates the traditional Depth of Field Preview function, stopping down the lens so that you can see the effect of your chosen aperture. Located in front of the shutter button is one of the e-dials, predominately used to change the shutter speed, while behind it are the Exposure Compensation and ISO buttons - these commonly-used functions are now ideally located for easy access. Pentax have retained the traditional top LCD panel which displays quite a comprehensive amount of information about the current camera settings, including the shooting mode, current aperture or shutter speed, flash mode, battery level, number of remaining frames and drive mode. A similar amount of settings are also displayed in the viewfinder. In addition, when you turn the K-7 on or change the shooting mode, a graphical overview of how that mode operates is briefly displayed on the rear LCD screen. The Pentax K-7 does a very good job of providing easily understood information about the settings that it's using.

The Pentax K-7 has a traditional eye-level optical TTL viewfinder which offers an impressive 100% scene coverage, beating both the Canon EOS 50D and Nikon D300. Being able to see exactly what will be captured means that you can only blame yourself for poor composition and unwanted details creeping into the frame. The viewfinder is bright and free of any distortions or aberrations, making it suitable for both auto and manual focusing. It also features a new Natural-Bright-Matte III focusing screen to improve focusing accuracy during manual-focus operation. The in-finder status LCD runs horizontally along the bottom and it shows most of the camera's key settings.

The rear of the camera is dominated by the large 3 inch LCD screen. The K-7's LCD screen has a very high resolution of 920K dots, wide viewing angle and it remains visible outdoors in all but the brightest of conditions, making it one of the best LCD screens that we've seen on a DSLR. The colour temperature of the screen can be modified if you think it doesn't match that of your calibrated computer monitor, but the contrast and gamma cannot be altered. Gripping the K-7 with both hands means that the glass of the screen inevitably soon becomes covered with thumbprints, though this is true of most DSLRs in its class. The rear screen also doubles as a comprehensive status display, which can be called up by pressing the OK button in record mode. If you then press the INFO button, you can also change all the settings right on the screen using a combination of the navigation pad and the rear e-dial. This ingenious solution spares you the pain of having to enter the menu, and makes most setting changes very simple.

Located above the LCD screen and to the left of the viewfinder are the self-explanatory Play and Delete buttons. To the right of the viewfinder is the rear e-dial, mainly used for changing the aperture, and the AE-L button, handily placed for locking the exposure. Underneath the rather innocuous looking button with a small green dot is unique to the K-7. It has two uses - firstly, when shooting in Manual mode, a single push of the green button allows you to instantly set the correct exposure for the subject, as calculated by the camera, useful if you need a starting point for your own exposure. Secondly, the K-7 offers a Hyper Program function which instantly switches to either the Shutter-Priority or Aperture-Priority mode from the Program mode, simply by turning either of the control dials on the grip. Pressing the Green button then returns to the Program mode.

The AF button is an alternative way of locking the focus, surrounded by the Autofocus Area switch which can be set to Centre AF, Auto/All 11 AF points, or User Selectable. The new LV button turns on the K-7's Live View mode (see below for more details). The traditional 4-way navigation pad is split into separate buttons, providing instant access to the drive mode/self-timer, custom image, flash and white balance settings, with the OK button confirming actions. The Menu button accesses all of the 89 different menu options that the camera offers, reflecting the fact that this a complex and very customisable DSLR. Thankfully you will only have to set about half of the settings once and can then forget about them. The menu system has a fairly logical tabbed system with four main tabs, Rec. Mode, Playback, Set-Up and Custom Setting, each divided into several sub-pages, and it's easily readable with a bright display and a large font size making it perfectly visible even in low light.

Pentax K-7 Pentax K-7


Live View has thankfully been greatly improved on the K-7, offering a much more usable system than the K20D. You can use it to hold the K-7 at arm's length or mount the camera on a tripod, with a single press of the new LV button on the rear displaying the current scene on the LCD screen. Focusing is still achieved by pressing the small AF button on the rear of the camera, rather than half-pressing the shutter-button, which is less intuitive. Thankfully the LCD screen no longer blanks out momentarily, making it much easier to use Live View for tracking a moving subject. In theory at least - unfortunately the AF system in Live View mode takes several seconds to lock onto the subject, even if it's stationary, making it much better suited to subjects that don't move. The new Face Recognition AF mode does work quite well, as promised quickly identifying people in the frame, but again it takes a couple of seconds to lock onto a non-moving subject. Impressively Live View can be used in the continuous shooting mode with no restrictions on the 5.2fps rate, as the K-7 sets the mirror to the lock-up position.

Alternatively you can use manual focus in Live View mode, with up to 10x magnification available via the Info button to help you fine-tune the focus (you can also use the Info button to magnify the subject by up to 6x when Auto Focus is on). All of our main criticisms of the K20D's Live View mode have been addressed on the K-7. Most of the main camera settings are displayed, including a helpful electronic level that helps to keep your horizons straight, although a histogram is still conspicuous by its absence. You can now change the aperture, shutter speed, exposure compensation, ISO speed and a number of other settings when Live View is activated, which means that it's much more than just a glorified version of the Digital Preview option, as on the K20D. A big improvement then, let down only by the slow and hit-and-miss AF system.

Live View is also used for the feature that will generate a lot of interest in the Pentax K-7: its movie mode. This is the first ever Pentax DSLR camera to shoot HD quality video, recording high-definition video at either 1536 x 1024 pixels or 1280 x 720 pixel resolution at 30fps in the Motion JPEG (AVI) format. Video can also be recorded at 640 x 416 pixels at 30fps. The maximum size of a single video clip is either 4 gigabytes or 25 minutes. There's a built-in microphone for mono recording and also a socket for connecting an external stereo microphone. It also has an HDMI port for playback on a HD TV, using the industry-standard HDMI mini-out connection, but note that you'll need to purchase a suitable cable separately. You can also still connect the K-7 to a standard TV set via NTSC/PAL.

By offering video capture in a DSLR, Pentax has made it possible for filmmakers to play with depth of field the way they never could, taking advantage of the relatively big APS-C image sensor and the wide assortment of Pentax lenses. There are, however, some notable drawbacks to the Pentax K-7's video mode. It's quite difficult to actually start recording one. You have to set the Mode Dial to the Movie mode, then the AF-On button to set the focus, then press the shutter button to begin recording (with the same button ending the movie). It's not on a par with the one-button system that some rivals offer, and you can't take a still shot during recording either. As with all other DSLR cameras that have a vidoe mode, you can't autofocus during movie recording. Focusing manually is the only option, although most AF lenses have MF rings with very little 'travel' between their close-focus point and infinity, and in a quiet environment it's also possible to hear the sound of the focusing ring in the video.

In addition you can't set the aperture from the camera during recording, only before, so you will want to use lenses that have an aperture ring if possible. The K-7 can be set to Auto Aperture Control, which removes the flexibility of being able to set the aperture yourself but at least enables the camera to change it during recording to suit the subject matter. The shutter speed cannot be set by the user in movie mode either, so you will have to rely on the camera's auto-exposure system while filming. Handholding the K-7D and shooting video is very difficult, with the DSLR form factor not lending itself well to controlled shooting at arm's length. It's a much better idea to mount the camera on a dedicated video tripod. Casual users hoping to grab some quality footage of the kids may be put off by the inherent difficulties of shooting video using the relatively alien SLR format.

The Pentax K-7 features an improved Shake Reduction system. Turn it on via the main menu option and the K-7 automatically compensates for camera shake, which is a slight blurring of the image that typically occurs at slow shutter speeds, providing approximately 2.5 to four shutter steps of compensation. As this system is built-into the camera body, it works with almost any lens that you attach to the K-7, providing a significant cost advantage over DSLRs from Canon and Nikon, which use a lens-based image stabilisation system (compatible lenses are the PENTAX K-, KA-, KAF-, KAF2- and KAF3-mount lenses; screw-mounted lenses (with an adapter); and 645- and 67-system lenses (with an adapter)). In practice I found that it does make a noticeable difference, as shown in the examples on the Image Quality page. You don't notice that the camera is actually doing anything different when Shake Reduction is turned on, just that you can use slower shutter speeds than normal and still take sharp photos. The K-7 also displays a blur icon in the viewfinder to warn you that camera-shake may occur, regardless of whether or not Shake Reduction is on.

If you've had a bad experience with DSLRs and dust in the past, then the K-7 offers an improved Dust Removal mechanism. This automatically shifts the low-pass filter located in front of the CMOS image sensor at very high speed, shaking the dust off the low-pass filter. I didn't experience any issues with dust during the 3 weeks of this review. If you do, there's a neat feature called Dust Alert which is designed to show exactly where the dust is on the image sensor. A vertically and laterally correct image of the sensor shot at f/16 is shown on the LCD screen, indicate exactly where any stubborn dust particles may be lurking. While this feature won't prevent dust from getting onto the sensor, it does provide a quick and easy way of checking for it. In addition Dust Removal can be set to activate whenever the camera is turned on, and you can also use the built-in Sensor Cleaning function to lift the mirror and clean the image sensor with a blower brush or third-party cleaning solution.

Pentax K-7 Pentax K-7
Memory Card Slot Battery Compartment

The Pentax K-7's HDR Capture option (only available for JPEGs) takes three images with different exposures, and then records a single image that combines the properly exposed parts of each one, expanding its dynamic range. It's important to always use a tripod to prevent camera shake from blurring the HDR image, and it doesn't work very well for moving subjects. Similar to Nikon's D-lighting, Sony's DRO, and Olympus' Shadow Adjustment Technology, Pentax's D-Range allows you to correct the highlights (On or Off) and/or the shadows (3 different levels) before taking a JPEG or RAW image. Although this option is always at your disposal, remember that it is meant to be used in strong, contrasty lighting at base ISO. The Pentax K-7 also has a multi exposure mode that allows you to combine between two and nine different JPEG or RAW images into a single photo.

Pentax's Custom Images, similar to Nikon's Picture Styles and Canon's Picture Controls, are preset combinations of different sharpness, contrast, saturation and colour tone settings. You can change the saturation, hue, high/low key, contrast and sharpness for each of the seven options?. The Pentax K-7 additionally offers seven different Digital Filters, which allow you to quickly apply an artistic effect to a photo before taking it (JPEG images only). Note that applying the Digital Filters slows the camera down somewhat, as it has to process the image for a few seconds after it's taken. The K-7 can also be set to automatically compensate for both distortion and lateral chromatic aberration of any DA- and DFA-series lenses.

The rather innocuous-sounding AF Adjustment custom function will be of particular interest to current Pentax owners. If you have a collection of older Pentax lenses and you've never been quite sure how accurate they focus when mounted on a DSLR, this is the function for you. Essentially it allows you to alter the focus of each lens. You can use a focusing target like the new LensAlign range of products to test if the lens focuses correctly, and if it doesn't alter it slightly using the AF Adjustment option, then test again until perfect focus is achieved. With all other DSLR systems you'd have to send the camera and lens off for calibration (and maybe even have to pay for it), but with the K-7, you can calibrate all of your lenses in the comfort of your own home.

The start-up time of the Pentax K-7, from turning the camera on to being ready to take a photo, is very quick for at around 1 second. Focusing is also quick and consistent in good light with the standard 18-55mm kit lens, a marked improvement on previous Pentax DSLRs, with the 11 point AF system offering fairly generous scene coverage, and the camera happily achieves focus indoors and in low-light situations. Note that the 18-55mm lens has an annoyingly loud focusing mechanism though. Unlike the K20D, the powerful AF Assist lamp can be used even the built-in flash isn't raised.

It takes about 1 second to store a JPEG image at the highest quality setting with no discernible lockup between taking shots, allowing you to keep shooting as they are being recorded onto the memory card. For RAW images the Pentax K-7 takes about 2 seconds to store an image and again there is no lockup between shots. In the continuous shooting mode you can hold down the shutter button and take 5 shots per second for up to 40 JPEGS or 15 RAW files, an impressive performance given the large 14 megapixel files that this camera produces. The camera does lock up for a few seconds once the maximum number of shots is reached, although you can continue to shoot continuously, just at a much slower rate.

Once you have captured a photo, the Pentax K-7 has a good range of options for playing, reviewing and managing your images. You can instantly scroll through the images that you have taken, view 9 thumbnails, zoom in and out up to a magnification of 32x, and see very detailed information about each image by pressing the Info button. You can also delete, rotate, resize, protect and crop an an image, view a slideshow and set various printing options. There are an expanded range of digital effects available which can be applied to JPEGs - Black and White, Sepia, Color, Extract Color, Soft, Illustration, High Dynamic Range, Slim and Brightness. The camera shows you a preview of what the effect will look like when applied, and the effect is applied to a copy of your image, thus preserving the original intact.

Image Comparison allows you to compare two images side-by-side complete with zoom. The Index option creates an index print from up to 36 images, Save as Manual WB sets the camera's Manual White Balance setting to the colour balance of the current image, and RAW Development converts a RAW file into a JPEG or TIFF with various conversion parameters available. Importantly the Pentax K-7 offers a histogram after taking a photo which is a great help in evaluating the exposure, plus any areas that are over-exposed flash on and off in the LCD preview to show you want you should be compensating for with your next attempt.

If you have never used a digital camera before, or you're upgrading from a more basic model, reading the comprehensive but relatively easy-to-follow manual before you start is a good idea. Thankfully Pentax have chosen to supply it in printed format, rather than as a PDF on a CD, so you can also carry it with you for easy reference.