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Originally Posted: September 29, 2009
Last Updated: October 1, 2009
The Pentax K-7 ($1299, body only) is a midrange D-SLR offering build quality and features usually found on cameras often costing hundreds of dollars more. Here are the highlights:
And there's even more neat stuff than the K-7 can do, that I'll touch on throughout this review. The K-7's main competitors are the Canon EOS-7D ($1699), Nikon D300s ($1799), and the Olympus E-3 ($1299), at least in my opinion.
Is the K-7 a powerful camera at a great price point? Find out now in our review!
The K-7 is currently sold in a body only kit. The contents of the bundle are pretty standard for a digital SLR, and they include:
Since the K-7 does not include a lens, you'll need to supply your own. The camera works with essentially all Pentax K-mount lenses -- even screw-mount and medium format models (though an adapter is required for the latter). The most modern lenses will support things like lens correction and auto focal length info transfer for shake reduction. Whichever lens you end up using, there's a 1.5X focal length conversion ratio, so that 50 mm lens of yours will have a field-of-view equivalent of 75 mm.
As with all D-SLRs, Pentax does not include a memory card in the box with the K-7. So add that to your shopping list too, unless you already have one. The K-7 supports SD and SDHC media, and I'd recommend a 4GB card to start with. It's definitely worth spending a little extra on a high speed card (Class 6 should be perfect), especially if you'll be recording HD movies.
The K-7 uses the brand new D-LI90 lithium-ion battery for power. This is one of the most powerful batteries I've seen in a digital SLR, with a whopping 13.4 Wh of energy. Think that translates into great battery life? Let's have a look:
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As you can see, the K-7 has some tough competition. Despite putting up 740 shots per charge, it still comes in third place!
I should mention the usual caveats about the proprietary batteries that are used on all of the camera listed above. First, extra batteries are pricey -- a spare D-LI90 will set you back at least $49. Second, you can't use an off-the-shelf battery when your rechargeable dies -- well, unless you have this:
Here you can see the K-7 with its optional D-BG4 battery grip ($229). Like the camera itself, the grip is weather-sealed against dust and moisture. This grip can hold an extra D-LI90 battery (you leave the other in the camera), giving the K-7 the ability to take 1480 shots before you need to recharge. It can also hold three AA batteries for emergencies (or if you just prefer using them). And, of course, the grip features lots of extra buttons that will come in handy when you're shooting in the portrait orientation.
When it's time to charge the D-LI90 battery, you can just pop it into the included charger. It takes this charger a whopping 6.5 hours to fully charge the D-LI90, so you might as well do it overnight. This isn't one of those chargers that plugs right into the wall -- you must use a power cable.
Being a digital SLR, you shouldn't be surprised to hear that there are a ton of accessories available for the K-7. Here are the most interesting ones:
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Not too shabby!
Pentax Digital Camera Utility 4 for Mac
Pentax includes a single software product with the K-7, and that's their Digital Camera Utility version 4. This software, for Mac and Windows, is based on SilkyPix, which is often bundled with other RAW-capable cameras. Thankfully, the interface in the Pentax Utility is a lot cleaner than in regular SilkyPix.
This software can be used in a few ways: for acquiring images from your camera, for managing them in a lightbox-style interface, and for performing some pretty heavy-duty edits (for RAW images, specifically). The editing tools are quite powerful, and can be used for both JPEG and RAW images. Here are some of the things that you can do:
In other words, this software covers just about anything you can possibility imagine. I should also add that Pentax Utility supports batch processing, and the whole user interface is quite customizable.
If you want to use Photoshop CS4 or a recent version of Photoshop Elements to work with the K-7's RAW files, you'll just need version 5.4 or newer of the Camera Raw plug-in.
What's the deal with RAW images anyway? These files contain unprocessed data straight from the camera's CMOS sensor. The benefit of this is that you can tweak many camera settings (white balance, exposure, color) without reducing the quality of the image. It's almost like getting a second chance to take a photo. The downsides are the need to post-process the images on your computer, and the huge file sizes, which reduce camera performance and quickly fill up your memory card. The K-7 is somewhat unique in that it supports two RAW formats. You can use Pentax's own PEF format, or Adobe's somewhat-of-an-open-standard DNG.
Pentax includes a enormous manual with the K-7, and you'll need it for this complex camera. As camera manuals go, this one is pretty good. It has large type, helpful tips and tricks, and a minimum of "notes" on each page. Documentation for the included software is installed onto your Mac or PC.
The Pentax K-7 is a midsize digital SLR with excellent build quality for its price. The body is made of magnesium alloy, and it has numerous seals to protect the camera's innards from moisture and dust. I should add that the battery grip and the 18-55 and 55-200 WR lenses I used with the K-7 are also sealed. The K-7 can be used in cold temperatures (as low as 14F/-10C) -- the Canon 7D and Nikon D300s are not rated below 32F/0C.
The camera has a large, rubberized grip that gives it a secure feel in your hands. The K-7 does have more than its share of buttons, switches, and dials, and it can be a little intimidating at first. I also wasn't a huge fan of how the dual control dials are placed -- your fingers sit right on them, making it quite easy to accidentally adjust the exposure.
Now let's see how the K-7 compares to other D-SLRs in its class, in terms of size and weight:
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As you can see, the K-7 is both the smallest and lightest camera in the group. That doesn't mean that it'll be traveling in any of your pockets, though. It will, however, fit comfortably on your shoulder, or in a camera bag.
Enough chit-chat, let's get to the tour of the camera now!
Here's the front of the K-7 without a lens attached. The camera supports all Pentax K-mount lenses, plus old screw-mount and 645/67 medium format lenses (adapter required for those). All but the oldest lenses should support autofocus, and most will work with the camera's image stabilizer right out of the box. The more modern DA, DA L, and D FA lenses support automatic aberration and distortion correction, as well. To release a lens, simply press the button to the lower-left of the mount.
Inside the lens mount, behind the mirror, you'll find the K-7's 14.6 Megapixel CMOS sensor, which is manufactured by Samsung. The sensor is mounted on a movable plate, which is used for both image stabilization and composition adjustment (discussed later). The camera detects the tiny movements of your hands that can blur your photos, especially in low light, or when using a telephoto lens. The K-7 shifts the sensor to compensate for this motion. The image stabilizer not only compensates for the up and down / side-to-side motion that can cause blurry photos -- it now handles rotational motion as well. Want to see the IS system in action? Here, have a look:
Image stabilization off
Image stabilization on
I took both of the photos you see above a shutter speed of 1/8th of a second. As you can probably tell, the photo taken with IS is noticeable sharper than the one without. Some of the stuff toward the back of the photo still looks blurry, but that's just a depth-of-field issue. You can also use image stabilization in movie mode, and you can see a quick sample of how well that works in this video clip.
Straight above the lens mount is the K-7's pop-up flash. As you can see, it pops up pretty far from the lens, which is good news for both redeye and vignetting with certain lenses. The K-7's flash is one of the most powerful you'll find built into a digital SLR, with a guide number of 13 meters at ISO 100. The built-in flash can also control two or more wireless flashes, which allows for some creative lighting setups. If you want to physically connect an external flash to the camera, I'll show you how in a moment.
Moving over to the left side of the body, you'll find the AF-assist lamp, front control dial, and the self-timer lamp/remote control receiver combo. The camera uses the AF-assist lamp as a focusing aid in low light situations. It's nice to see that Pentax used a dedicated lamp here, instead of relying on the flash like on some other D-SLRs.
The first thing to see on the K-7's busy backside is its large 3-inch LCD display. Pentax spared no expense on this screen -- it has 921,000 pixels, so everything is razor sharp. Outdoor visibility is pretty good, though I've seen better. The screen is used for menu navigation, displaying current camera settings, reviewing photos you've taken and, of course, live view.
The live view shows a histogram (lower right), electronic level (top left, hard
to see), and more
The live view experience on the K-7 is quite nice. You've got two AF modes to choose from (contrast detection and phase difference, with face detection available for the former) plus a live histogram, composition grid, and an electronic level. The electronic level is quite handy, helping reduce the likelihood of one of my biggest problems: crooked horizons. The image on the screen is sharp and bright, and motion is quite fluid. The screen brightens up nicely in low light, so you can still see your subject. To begin the live view experience, simply press the dedicated LV button on the back of the camera.
The achilles heel of live view has always been autofocus performance. The K-7 offers three AF modes: contrast detection, contrast detection w/face detection, and phase difference, and you activate each of them via the AF button on the back of the camera. Contrast detect uses the CMOS sensor to focus, just like a compact camera does. Unlike on a compact camera, contrast detect AF on nearly all D-SLRs (K-7 included) is very slow. Focus times easily exceed one second, and can more often be two or three. The only real benefits of this mode are 1) you don't lose the live view while the camera is focusing, 2) you get face detection, and 3) you can select the exact spot in the frame on which to focus. For tripod use, that may be acceptable.
My favorite AF mode is phase difference, which is easy to turn on via an option in the menu system. When you press the AF button, the K-7 flips the mirror down, focuses using the same AF sensor as it would if you were using the optical viewfinder, flips the mirror back up, and restores live view. That may sound like it takes a long time, but it's really around a second-long delay.
Enlarged frame in manual focus mode
Live view is perhaps most useful when you're focusing manually. There, you can enlarge the frame (from 2X to 10X), which allows for very precise focusing. The image quality is a bit lacking when you're zoomed in, though.
Live view also also the place you'll record movies -- but I'll save that for later.
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| Info display | Quick access to camera settings via the Control Panel |
When the LCD isn't being used for live view, it can be turned into an information display, much like the one on the top of the camera. An additional screen (accessed by pressing the Info button) lets you adjust numerous camera settings (see screenshot). These settings include:
Needless to say, I'll explain all of those in detail when I get to the menu section of this review. I should add that you cannot get to that info screen while in live view, which would've been nice.
Enough about the LCD already -- let's get back to our tour now! Directly above the LCD is the K-7's optical viewfinder. While its 0.92X magnification doesn't make it largest viewfinder in its class (the EOS-7D and D300s both have it beat), but it's still pretty good-sized. Like all of its competitors, the K-7's viewfinder displays 100% of the frame. Under the field-of-view is a line of green-colored data. In addition to showing all the usual things (shutter speed, aperture, focus lock, shots remaining), you can also see the same electronic level that I mentioned a moment ago. You can adjust the focus of the viewfinder by using the diopter correction slider located on the top of it.
To the left of the viewfinder are buttons for entering playback mode and deleting a photo. On the opposite side we find that easy to accidentally turn rear command dial, and the AE Lock button.
Moving downward, the next thing you'll encounter is the famous Pentax "green button". In most shooting modes, this button returns the camera to default exposure settings. When pressed in combination with the ISO button (on the top of the camera), you can switch between fixed and auto ISO. If you're in TAv or M mode, the green button will let you select whether you're adjusting the shutter speed, aperture, or both.
Under that is the focus mode dial, with the AF button inside it. You can have the camera select one of the eleven focus points automatically, you can select one yourself, or just use the center point. Normally, pressing the AF button inside that switch activates the AF system, but you can also have it do the opposite, for when you want to focus manually.
Continuing south, we find the Live View button, with the four-way controller next to it. The four-way controller does a whole bunch of things, the least of which is menu navigation. You can use it to select a focus point, moving through photos you've taken, and also:
Plenty to talk about before we can continue the tour. Let's start with the drive options, specifically the two continuous shooting choices. There are low and high speed continuous modes, and here's what kind of performance you can expect from the K-7:
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While the K-7 doesn't have the fastest burst rate in its class, it still offers very good performance, and a healthy amount of buffer memory. While the JPEG numbers don't look overly impressive, you can keep shooting until the memory card fills up if you lower the quality setting a notch. A couple of other notes: when you reach the buffer limit shown above, the camera doesn't stop shooting -- it just slows down considerably. If you're shooting in live view mode, the screen goes black as soon as the burst starts. When it's done, live view returns. Also, I found no appreciable difference in performance between the PEF and DNG RAW formats.
The drive menu is also where you'll find one of the many bracketing options on the K-7. Here, it's for exposure, and you can take three or five photos in a row, each with a different exposure value. The interval between shots can be anywhere from ±0.3EV to ±2.0EV. I especially like how you the camera can 1) use the self-timer and bracketing features at the same time and 2) take the whole sequence with only one press of the shutter release button.
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| Lots of white balance choices | Plus the ability to fine-tune |
The K-7 has a full set of white balance options. The usual presets like tungsten and sunlight are just the beginning. You can also use a white or gray card for "custom" white balance. Any of those can be fine-tuned, as you can see in the screenshot above. You can also set the color temperature manually, in either Kelvin or mired. If that's still not enough, the K-7 can bracket for white balance, as well. There's also a unique Color Temperature Enhancement (CTE) option, which Pentax describes as the opposite of auto white balance. For example, if the camera is using a high color temperature, CTE will crank it up a little higher, to emphasize the colors in the scene.
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| All the Custom Image sets | Tweaking the sharpness of the "bright" set |
The Custom Image feature is similar to Picture Styles on Canon D-SLRs, and Picture Controls on Nikon's cameras. A Custom Image set contains various exposure and color settings, and there are seven presets available: bright (default), natural, portrait, landscape, vibrant, muted, and monochrome. There aren't any "custom" sets, though -- you have to modify one of the presets. For each of these you can adjust the following:
Finally, I can point out the last two buttons on the back of the K-7. One toggles the information shown on the LCD, while the other enters the menu system. And we're done!
The first thing to see on the top of the K-7 is its mode dial, which is located with manual exposure options. Under the mode dial is a switch for adjusting the metering mode (multi-segment, center-weighted, spot). The mode dial has a handy locking mechanism to keep you from accidentally turning it -- something that more cameras could use, in my opinion. Here are the options on the mode dial:
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There's not a scene mode in sight on the K-7's mode dial, which should tell you something about its target market.
You can even select the Program Line on the K-7
The camera has some really unique shooting modes, like hyper program, sensitivity priority, and shutter & aperture priority modes. But wait, there's more -- you can actually select what Program Line is used in many shooting modes. Select from auto, normal, high speed priority, deep DOF priority, shallow DOF priority, and MTF priority. I can't think of another camera that lets you do that.
Moving toward the center of the above photo, you'll find the K-7's hot shoe, as well as its (monaural) microphone. For best results, you'll want to use one of the Pentax external flashes I mentioned back in the accessory section, as they'll integrate with the camera's metering system. Do note that the cheapest flash (AF200FG) doesn't support a whole lot of features, so you'll want to bring out the big guns (AF360FGZ and AF540FGZ) for high speed flash sync, external AF-assist, and wireless support. If you're not using a Pentax flash, you'll probably have to set everything manually. The maximum flash sync speed on the K-7 is 1/180 sec.
Continuing to the right, you'll see the K-7's LCD info display. You name a camera setting, and it'll be on this screen: shutter speed, aperture, shots remaining, whether you're using bracketing, the drive mode, etc, etc. The screen has a very bright green backlight that turns on whenever you press a button on the camera.
Above that are a pair of buttons. The one on the left adjusts the exposure compensation (-5EV to +5EV), while the one on the right lets you select the ISO (100 - 3200, expandable to 6400). You can switch to Auto ISO by holding down the ISO button and pressing the green button. I'll have more on that feature later.
The last thing to see on the top of the K-7 is the shutter release button, which has the power switch wrapped around it. The power switch doesn't just turn the camera on and off -- it's also how you access the preview feature. There two preview options here -- a traditional depth-of-field preview, plus a digital option which takes a test photo but doesn't save it (unless you want to).
There's plenty more to see on the side of the K-7. Starting near the top of the photo, you can see the release for the pop-up flash. Right under that is the flash sync port, which has its plastic cover on in this photo. This is the third way in which you can use an external flash with the K-7, in addition to via the hot shoe or wirelessly.
Continuing down, we find the RAW button. You can press this to switch to quickly switch from JPEG to RAW, RAW to RAW+JPEG, or whatever combination you please.
Under that is the focus mode switch, with options of single, continuous, and manual AF. Single AF locks the focus when you press the shutter release halfway. Continuous AF keeps focusing, even with the shutter release pressed (which is desirable when your subject is moving). Manual focus pretty much speaks for itself.
At the far right of the photo are the camera's I/O ports, which are kept behind sealed rubber covers. Let's peel it back for a closer look:
The ports here include:
Every midrange D-SLR seems to have a mini-HDMI port these days, and the K-7 is no exception. The cable is not included, so you'll need to pick one up if you want to connect to an HDTV.
The K-7 also supports an external stereo microphone, which plugs into the mini-jack at the top of the photo.
On the other side of the camera you'll find its SD/SDHC memory card slot, which has a sealed plastic door of decent quality protecting it. I did find that the gasket that seals this door makes it a bit difficult to extract the memory card (how's that for a petty complaint?).
Our tour ends with a look at the bottom of the K-7. Here you'll find a metal tripod mount (inline with the lens, naturally), the battery grip connector (which has a rubber cover on it here), and the battery compartment itself. The door over the battery compartment has an elaborate locking system that will make sure that you'll never open it by accident.
The included D-LI90 lithium-ion battery can be seen at right.
Record Mode
Flip the power switch and the K-7 is ready to start taking pictures almost immediately. The dust reduction cycle runs at startup time, and you'll hear it, believe me.
Autofocus speeds depend on a number of factors, such as what lens you're using, and whether you're using live view. When shooting with the viewfinder and Pentax's two new "WR" lenses (18-55 and 55-200), the camera focused very quickly. Wide-angle focus times were between 0.1 and 0.3 seconds, with telephoto times of about 0.3 - 0.6 seconds. In other words, impressive. Low light focusing was generally very good, with focus times usually staying at a second of less, though I caught the camera going over that on a handful of occasions.
Live view autofocus speeds are a whole different ball of wax. If you're using either of the contrast detect modes, expect a delay of at least one second before the camera locks focus. More often than none, it'll be 2 or 3 seconds. In low light, things can be even slower. For best results, use the phase difference AF, which has the same focus speeds as the viewfinder, with about a second-long delays while the mirror flips down and then back up.
As for shutter lag, there won't be any if you're shooting with the viewfinder, or using contrast detect AF in live view. If you're using phase difference AF in live view, there's about a second of lag due to the mirror flipping action.
Shot-to-shot delays are minimal, regardless of the image quality setting or whether you're using the flash.
There's no way to delete a photo immediately after it is taken -- you must enter playback mode first.
Now, here's a look at the available image size and quality choices on the K-7:
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Now those are some gigantic files! The K-7 supports two RAW formats: Pentax's proprietary PEF, or Adobe's open standard DNG. The advantage of DNG is that you can open the files in a lot more software applications than you can PEF.
The K-7 can take a RAW image alone, or along with a JPEG at the size of your choosing.
While Pentax has spent a lot of time packing the K-7 with innovative new features, one area that did not receive any attention is the menu system. It's the same clunky, antiquated menu system that has been on their cameras (compact and D-SLR) for years now. It gets the job done, but at the end of the day, it could really have used some refinement. The menu is broken down into four tabs, covering recording, playback, setup, and custom settings. Keeping in mind that not all of these options are available in each shooting mode, here's the full list:
Shooting options
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Playback options
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Setup options
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Custom options
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That is quite possibly the longest list of menu items I've typed up in years! I can't cover everything up there, but I will describe the most interesting and important features below, with examples whenever possible.
Let's start with the two dynamic range settings: highlight correction and shadow correction. Highlight correction is something that is turned on or off (it's off by default). It boosts the ISO to a minimum of 200, and then does its stuff. Shadow correction can be turned off (which is the default) or set to low, medium, or high. Here are examples of both:
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| Highlight correction off View Full Size Image |
Highlight correction on View Full Size Image |
I'm the first to admit that this example isn't perfect, since the composition is off slightly (I did not have my tripod at the time). Still, since it's a great example of this feature, and further testing at more boring locations confirmed that highlight correction does work, I'm using it. You can see the highlight correction brings back details in the floor, on the column and arches on the right, and the sky and trees in the background. You can also see that there's a bit more noise in the shadows, as well.
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| Shadow correction off View Full Size Image |
Shadow correction low View Full Size Image |
Shadow correction med View Full Size Image |
Shadow correction high View Full Size Image |
In this example (taken in a similar hallway at another local college) you can see what the various shadow correction settings do. It definitely works, though it's on the subtle side. I should add that both highlight and shadow compensation can be adjusted when you're working with RAW images in Pentax Digital Camera Utility.
Lens correction is another neat trick the K-7 can pull off. Some cameras, notably from Panasonic, already apply distortion and chromatic aberration correction to photos you're taking, and those are both optional here. You can correct for lens distortion (both barrel and pincushion) as well as lateral chromatic aberration. You'll find an example of the barrel distortion correction in action a little further down the page, in the photo test section. As for the chromatic aberration correction, I performed a test that produced some pretty nasty fringing, and I saw little to no difference with the correction feature turned on. Do note that both distortion and lateral CA correction require some extra processing time after you take a photo. In addition, these features only work with modern DA, DA *, and DA L lenses.
Oh, my
The K-7 can bracket for more things than any camera I've ever tested. I already told you about exposure bracketing -- here's what else you can bracket for:
In case you're wondering, the K-7 can bracket for one of those plus exposure at the same time!
The HDR Capture feature takes three exposures in rapid succession and combines them into a single image with high dynamic range. One image is underexposed, another is overexposed, and the third is of normal exposure. Since the images need to be precisely aligned, a tripod is essentially required for this feature. You can apply "standard" or "strong" HDR enhancement to a photo. Here's an example of both settings:
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| HDR off View Full Size Image |
HDR standard View Full Size Image |
HDR strong View Full Size Image |
You can see why I picked this scene! I wanted the camera to pay the most attention to the bright white church in the background, and that's exactly what it did with the HDR feature turned off. As a result, the statue on the left and tree on the right are pretty dark. When you use standard HDR, the triple exposure combo brightens things up considerably, making the photo a lot more appealing. The "strong" setting gives the scene a washed out, almost ethereal quality, though perhaps that's the point of it. Do note that image stabilization and RAW image supports are not available when using HDR capture, and the camera takes several seconds to process a photo after you've taken it.
Two other features that involve multiple exposures are worth a brief mention. The multi-exposure feature lets you combine anywhere from two to nine (!) exposures into a single image. You can choose to have the camera adjust the exposure (gain) automatically, if you'd like. The interval shooting (AKA time-lapse) does just as it sounds -- you can take up to 99 photos at a set interval (could be a minute, hour, or day). The AC adapter is required if the interval between shots is longer than a few minutes.
Image compensation feature description courtesy of Pentax
The composition adjustment feature is unique to the K-7. By using the sensor-shift mechanism, you can make precise adjustments to the composition of your photos. The sensor can shift 1 mm along the X/Y axis, and it can even rotate up to 1° in either direction. This feature comes in handy when you have the K-7 on a tripod and want to recompose the shot slightly without having to move the camera.
A related feature is called horizon correction. If you're like me and can't take a level shot if their life depending on it, listen up. The K-7 will automatically level a crooked photo for you, up to 1° with Shake Reduction on, or 2° with it turned off.
That's more than enough menu talk -- let's move on to photo quality now. With the exception of the night shot, everything you see below was taken with the new Pentax F3.5-5.6, 18 - 55 mm WR (weather resistant) lens.
The K-7 did a very nice job with our macro test subject. Colors are nice and vivid (not to mention accurate), and sharpness is just how I like it. I don't see any signs of noise, and I sure as heck wouldn't expect to.
The minimum focus distance to your subject depends on what lens you're using. For the new 18-55 WR lens, it's 25 cm. If you think you'll be doing a lot of macro photography, Pentax has three lenses for just that purpose, ranging from 35 mm to 100 mm.
The night shot, taken with the new 55-200 mm WR lens, wasn't quite as impressive. The main issues I have are that the photo is fairly soft, and that purple fringing levels are moderate in places. Bringing in enough light wasn't a problem, as you'd expect from a camera with manual exposure controls. I don't see anything resembling noise or noise reduction, thankfully.
Alright, let's use that same scene to see how the K-7 performs at its various ISO settings. I'll start with the low setting (ISO 100) and work my way up to the max of ISO 6400 (which you must activate via a custom function).
ISO 100 |
 ISO 200 |
 ISO 400 |
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 ISO 1600 |
 ISO 3200 |
 ISO 6400 |
There's not much to distinguish the ISO 100 and 200 shots. At ISO 400 you see a slight amount of grainy noise, but that won't hold you back. This noise becomes more obvious at ISO 800, though making a midsize or perhaps even a large print isn't out of the question here. That trend continues at ISO 1600 -- with details starting to disappear at this point. There's pretty significant detail loss at ISO 3200 and especially at 6400, so these are two settings that you'll probably want to avoid in low light situations.
Can you improve image quality by shooting RAW instead of JPEG? See for yourself:
| ISO 800 |
 JPEG, straight out of the camera |
 RAW -> JPEG conversion (ACR) |
 RAW -> JPEG conversion + NeatImage + Unsharp Mask |
| ISO 1600 |
 JPEG, straight out of the camera |
 RAW -> JPEG conversion (ACR) |
 RAW -> JPEG conversion + NeatImage + Unsharp Mask |
In both cases, you can see that there's a noticeable (though not dramatic) improvement when shooting RAW. I'll have more on this subject in a moment when we get to the studio ISO test.
| Night photos and discussion were updated on 10/1/09 |
Redeye is already unlikely on a digital SLR, since its flash is far away from the lens. To further reduce the risk of this annoyance, the K-7 can fire the flash before the photo is actually taken. Using this method, I got a redeye-free photo, as you can see above.
Distortion correction off
Distortion correction on
The first distortion test chart you see above was taken with the 18 - 55 mm lens with the camera at its default settings. As you can see, there's some noticeable distortion, plus some vignetting as well (which wasn't a problem in my real world photos). When you turn on the distortion correction feature, things look a lot better -- look at how much straighter the lines are now. I did not find corner blurring to be a problem with the 18-55 lens.
Now it's time for our normal lighting ISO test, which is taken in our studio. Since the lighting never changes, this test can be compared to other cameras I've reviewed over the years. While the crops below give you a quick idea as to the amount of noise at each ISO sensitivity, viewing the full size images is always a good idea. And with that, here we go:
 ISO 100 |
 ISO 200 |
 ISO 400 |
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 ISO 1600 |
 ISO 3200 |
 ISO 6400 |
The images from the K-7 are super clean all the way to ISO 800. At that point, you start to see a bit of noise, but a large print is still a piece of cake. There's still quite a bit of detail left at ISO 1600, and ISO 3200 is still usable for small or midsize prints -- especially if you shoot RAW. ISO 6400 is probably best saved for desperation only.
Here's that other RAW comparison I promised you a bit earlier:
| ISO 1600 |
JPEG, straight out of the camera |
 RAW -> JPEG conversion (ACR) |
 RAW -> JPEG conversion + NeatImage + Unsharp Mask |
| ISO 3200 |
JPEG, straight out of the camera |
 RAW -> JPEG conversion (ACR) |
 RAW -> JPEG conversion + NeatImage + Unsharp Mask |
While the JPEGs produced by the K-7 are pretty good, you can squeeze a bit more detail out of the camera by shooting RAW, as you can see.
Overall, the K-7 produces very nice photos, though I found that I really had to keep an eye on the exposure in order to get the best results. That's because the K-7 seems to underexpose fairly often, usually by 1/3 - 2/3 stop. Since I don't like having to go back to my photo spots and reshoot all my test photos, I bracketed all the photos I took with the K-7, and reviewed histograms frequently. The camera has really nice color -- it really "pops" out at you. Image sharpness is one of those things that is lens-dependant, and with the two (relatively inexpensive) lenses I used, I found things to be on the soft side. If you agree, you can increase the in-camera sharpening by using the Custom Image feature. The K-7 has a lot of pixels packed onto its APS-C sensor, and I did some some noise and noise reduction artifacting if I really inspected the images at 100% on my monitor. That said, both noise and noise reduction don't start to negatively affect image quality until you get to ISO 800. Purple fringing is also lens-dependent (though the sensor plays into it as well), and this problem did crop up on several occasions. You can try toying with the lateral chromatic aberration correction feature, though it didn't seem to make a huge difference. Better quality lenses would probably reduce that issue as well.
Don't just take my words as gospel, though. Have a look at our extensive photo gallery, and see for yourself!
Movie Mode
The K-7 is the first Pentax digital SLR to have a movie mode. The camera can record at three different resolutions: 1536 x 1024, 1280 x 720, and 640 x 416. Two of the three resolutions there are non-standard, and I'm not sure why Pentax chose them. Anyhow, you can record video with monaural sound (stereo sound requires an optional mic) until you hit the 4GB file size limit, or 25 minutes elapse. At the two highest resolutions, you'll hit the file size limit in 7.5 and 9.5 minutes, respectively. You can get longer recording times by lowering the quality (increasing the compression).
When you're recording movies, the image stabilizer is active. You can zoom in and out to your heart's content, the camera will not be continuously focusing. Thus, you'll need to manually focus if you use the zoom, or if you subject moves closer or further away from you.
Movie mode is a point-and-shoot experience. You can have the aperture remain the same throughout recording, or it can adjust as needed to maintain proper exposure (do note that this noise may be picked up by the microphone). Speaking of sound, I found that the K-7 could really use a wind cut filter, as its microphone picks up wind noise quite easily.
Movies are saved in AVI format, using the M-JPEG codec. File sizes are enormous: a 10 second clip can easily exceed 60MB.
Here are a few sample movies for you. For each, I'm offering the original, huge file, plus a downsized version for easier web viewing. First, here's a clip taken at the highest resolution. The quality is just fair.
View original movie (47.3 MB, 1536 x 1024, 30 fps, AVI/M-JPEG)
View recompressed movie (5.0 MB, 1536 x 1024, 30 fps, QuickTime/H.264)
Now, here are a pair of 1280 x 720 movies. The first one has a lot of wind noise but shows off the video quality. The second one is quiet, but less exciting (unless you like geese). These videos definitely look better than the one above.
View original movie (110.6 MB, 1280 x 720, 30 fps, AVI/M-JPEG)
View recompressed movie (11.1 MB, 1280 x 720, 30 fps, QuickTime/H.264)
View original movie (103.0 MB, 1280 x 720, 30 fps, AVI/M-JPEG)
View recompressed movie (10.9 MB, 1280 x 720, 30 fps, QuickTime/H.264)
Playback Mode
When I first glanced at the K-7's playback menu I thought "that's it?". Turns out that the camera has quite a few playback features, they're just not where you expect them. The basic features are slideshows, image protection, DPOF print marking, thumbnail view, and zoom and scroll. This last feature lets you enlarge an image by as much as 16X, and then move around. This can be very helpful for checking that your subject is properly focused, that eyes are open, etc.
Most of the other playback bells and whistles can be reached by pressing down on the four-way controller. There you'll find tools for:
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| RAW editing | Side-by-side image comparison |
Two of those features are worth some further discussion. The RAW processing option lets you take a RAW image, adjust its properties, and save the result as a JPEG or TIFF file. You can adjust the image type, quality, and color space, the Custom Image setting, white balance, sensitivity, high ISO noise reduction, plus shadow, highlight, and distortion correction. The side-by-side feature lets you look at two photos, with the ability to main the zoom and position for both.
One thing you won't find on the K-7 is any kind of movie editing tool. Even a trimming tool would've been a nice touch.
The K-7 can display plenty of information about your photos, including your choice of histograms. The camera moves from one photo to the next without delay.
The Pentax K-7 isn't just an excellent midrange digital SLR -- it's also an incredible value. It may not have the fastest burst rate or lowest noise in its class, but it offers more features per dollar than anything else out there. It has very good image quality, stellar build quality, snappy performance (in most situations), more manual controls than you'll need, unique exposure modes, an HD movie mode, and lots more. Downsides are few. The camera tends to underexpose, and its image are on the soft side. The movie mode could use some work, contrast detect autofocus is slow (when using live view), and the menu system looks like a relic of the last century. Ultimately, the K-7 is a high-end camera at a midrange price, and it's a great choice for Pentax owners looking to upgrade, or first time D-SLR buyers who want something more capable than an entry-level model.
The K-7 is a compact digital SLR with a very solid magnesium alloy body. Not only is it incredibly sturdy, it's also sealed against dust and moisture (as is the optional battery grip and the two new WR lenses). I found the camera very easy to hold, with a large, rubberized grip for my right hand. The K-7 definitely suffers from what I call "button clutter", so expect to read the manual a bit in order to understand what everything does. The only real design-related thing that I didn't care for is the placement of the control dials -- I often found myself adjusting the exposure when I had no intention of doing so. The K-7 uses a Samsung-designed 14.6 Megapixel CMOS sensor that is mounted to a movable plate. This sensor-shift plate serves several purposes: to clean dust off of the sensor (by rapidly vibrating), as an image stabilizer (that works on nearly every Pentax lens ever made), and to allow you to slightly recompose photos when the camera is on a tripod. The image stabilizer is somewhat unique in that it not only corrects for shake on the X and Y axis, but rotationally as well. On the back of the camera you'll find a large and very sharp 3-inch LCD display. You'll use this for live view, displaying menus and camera settings, and reviewing photos you've taken. Pentax has done a nice job with the live view experience on the K-7, with my only complaints being the sluggish contrast detect AF (typical for a D-SLR) and the poor quality of the image enlargement feature (when using manual focus). Don't worry though, there's a phase difference option too. The camera has a good-sized optical viewfinder as well that shows 100% of the frame.
I could spend about five more paragraphs talking about all the features on the K-7, so I'll have to restrain myself. In short, the K-7 has the kitchen sink, and then some. It has no point-and-shoot controls, but if you're a power user, you'll be smitten. You've got full manual controls, lots of white balance options, bracketing for everything imaginable, and shadow and highlight compensation. Want more? The K-7 has unique sensitivity priority and aperture+shutter priority modes, 37 custom functions, and a Custom Image feature that lets you tweak various image quality properties. If that's still not enough, there's also an electronic level, automatic horizon correction, and a high dynamic range feature. And did I mention that the K-7 supports two RAW formats, and can convert those images into JPEGs or TIFFs in playback mode? There's also an HD movie mode that records at two unusual resolutions (1536 x 1024, 640 x 416) plus the more conventional 1280 x 720. The movie quality isn't great at the highest resolution, the recording time limit arrives quickly (due to the HUGE file sizes), and there's no continuous AF, but it's still decent by D-SLR standards. It's a shame that most of these features are accessed by an outdated user interface that looks like it came off a Pentax Optio point-and-shoot from the late 1990s. Still, I'd rather have a great camera and an ugly menu system than the opposite.
The K-7 is a very capable performer. It may start with a bit of a whine (presumably due to the dust reduction cycle running), but it's ready to go right away. When shooting with the viewfinder, the camera focuses very quickly, at both the wide and telephoto ends of the lenses (at least those that I used). Low light focus times generally stayed at one second or less. If you're using live view with contrast detect AF, the news isn't as good. The camera can take one, two, or even three seconds to lock focus -- and that's in normal lighting. For better results, use phase difference AF -- you'll lose the live view for a moment and there's a bit of lag involved, but it's much faster. The shot-to-shot delays on the K-7 are minimal, as you'd expect. While it doesn't have the fastest burst rate out there, the K-7's sizable amount of buffer memory allows it to shoot for quite a while at over 5 frames/second. While not best in class, battery life was still excellent, and you can do even better with the optional battery grip (which can use AAs, by the way).
Photo quality is very good on the K-7, though you may need to tweak a few things to get to that point. The K-7's two biggest image quality issues are its tendency to underexpose by 1/3 to 2/3 of a stop, and the overall softness of its photos. The former is easy enough to deal with -- bracket your shots, or just crank the exposure compensation up 1/3 EV. If you too agree that the photos are a bit soft, then you may want to visit the Custom Image menu, and crank up the in-camera sharpening a notch or two. The rest of the news is more positive: the K-7 has pleasing, vivid colors. Noise levels are low through ISO 800 in low light, and ISO 1600 in good light. Purple fringing has a lot to do with what lens you're using, and it was moderate at times with the 18-55 and 55-200 mm WR lenses I used. Redeye was not a problem.
Despite a few flaws -- most of them being easy to work-around -- the Pentax K-7 is an excellent digital SLR, offering features normally found on cameras two or three times its price. Heck, some of the K-7's features won't be found on any other camera. While I doubt that folks with a lot of money invested in other D-SLR systems will be jumping ship for the K-7, owners of Pentax cameras or those just starting out will be lining up to get their hands on this camera, and well they should. The K-7 is a great camera for enthusiasts, and it easily earns my recommendation.
What I liked:
What I didn't care for:
The only other D-SLRs in the K-7's class are the Canon EOS-7D, Nikon D300s, and the Olympus E-3.
As usual, I recommend heading to your local camera or electronics store to try out the Pentax K-7 and its competitors before you buy!
Check out our gallery to see how the K-7's photo quality looks!
