Pentax K100D Review

Pentax K100D Overview

by Shawn Barnett
and Stephanie Boozer
Review posted: 08/28/2006
Review updated: 10/24/2006

The Pentax K100D, along with its sibling the K110D, are the company's first DSLR models to forgo the rather confusing "*istD" branding. Both share an identical (newly developed) body and feature set, with the exception of an anti-shake mechanism - found on the K100D, but not the K110D. Konica Minolta has used a similar CCD-shift based system for a while now, and it has offered the ability to stabilize images on almost every lens compatible with the camera body. The Shake Reduction system is said to have been developed by Pentax themselves, and to work with "almost all" existing Pentax lenses, although the company notes that "[certain] lenses may lose part of their functions".

The Pentax K100D has a sensor resolution of six megapixels, and accept lenses using the Pentax KAF lens mount. The stabilization mechanism - dubbed "Shake Reduction" - is undoubtedly the standout feature of this model. Focusing can be controlled automatically or manually, and uses a phase detection system with 11 points (nine of them cross-type) to determine focus. Images can be framed using a penta-mirror optical viewfinder, and reviewed on a 2.5" LCD display with a resolution of 210,000 pixels. A choice of program, aperture- and shutter-priority or manual exposure modes; 16-segment multi, center-weighted or spot metering; shutter speeds from 30 - 1/4000 second; user-selectable ISO sensitivity from 200 - 3200 equivalent, plus eight white balance modes including fully manual white balance let your creative juices flow. For fun snapshots, the K100D offers a range of automatic controls including eight scene modes and four Picture modes (the latter essentially being scene modes that have positions on the mode dial rather than being accessed through the LCD display). A five-mode flash strobe is also available, along with a two or twelve-second self timer.

The Pentax K100D stores images on optional Secure Digital or MultiMediaCards, in either Raw (uncompressed) or JPEG (compressed) formats. Connectivity includes both NTSC / PAL switchable video output and a USB 2.0 Hi-Speed computer link, as well as a DC input connection for powering the camera when batteries are impractical (in a photo studio, for example). Power otherwise comes from four AA or 2 CR-V3 batteries including disposable types, offering a little extra versatility when you're on the road and can't get to a power point to charge up.

Pentax K100D User Report

by Shawn Barnett

I have enjoyed my time with the Pentax *istD -- I mean K100D. Yes, it's going to take a little time for me to get used to the new/old name of the latest SLR from Pentax. I say "new" because they've finally left behind the ill-conceived *istD naming scheme that unnecessarily alienated so many. I say "old" because the K100D's name so closely matches the long-running mechanical film SLR, the K1000. Due to the similar shape of the D, you can even mistake the two.

The "new and old" theme continues with the K100D. This is actually the fifth Pentax digital SLR (or sixth, depending on where you live), so you can't exactly call the Pentax K100D an all-new camera. There was the *istD, *istDS, *istDS2, *istDL, and in some markets the *istDL2. The family resemblance is uncanny. However, the new image stabilization mode is indeed new, as is the new stainless frame. Also new is the K100D and K110D's backward compatibility with all of Pentax's old lenses.

That's right, Pentax claims the two new SLRs will work with "any Pentax lens ever produced." That includes their old K1000 35mm K-Mount and the even older M42 x 1mm screw mount lenses (which were made by many companies: Zeiss, Leica, Mamiya, Olympus, etc.), plus the Pentax 645 and 67 medium format lenses: all can be attached via special adapters. Naturally, many of these lenses are manual focus and won't autofocus with the K100D, nor will they return information to the camera to help gauge subject distance or any of the other niceties you get with the DA-series lenses. But image stabilization will work with any lens you can snap onto this camera, and not many digital SLRs can stabilize such an old lens. [Thanks to Max for correcting me on the K1000 screw mount reference, since it used a K-mount]

There are many holdouts who are waiting for a camera that will do this very thing: work with all pre-existing lenses in the line. So this will be a popular move for a select group of Pentax glass owners.

Fit & finish. Still among the smallest digital SLRs on the market, the K100D has an excellent feel of quality and a good heft. The grip is well-sculpted, with a reasonable size for most hands, and a comfortable shape. It has more of a flat surface for your fingertips bite into, unlike the *isDL, which had a curved surface where the inside of the grip met the camera body. This curve tends to made holding the camera for long periods rather uncomfortable. The K100D's grip material is textured and feels hard at first, but press a fingernail into it, and you find a thick, soft rubbery material.

With the camera held confidently in the right hand, my index finger rests atop the shutter button quite naturally. I slide my finger forward a few millimeters, pull the power switch to the right and I'm ready to shoot. As I raise the camera to my eye, my left hand comfortably cups the contoured left bottom corner. My eye finds the viewfinder with no trouble; though like most cameras, I'm forced to press my glasses up against the hard rubber eyepiece for a full view of the frame. The sliding diopter adjustment atop the viewfinder does not match my prescription, but I'm pretty used to shooting with glasses.

In Manual mode, Shutter speed is adjusted with the back dial, and Aperture is adjusted with the same dial when activated while pressing the small EV/Av button set just back from the shutter button. The combination is easy to adjust with your eye to the viewfinder. The Pentax K100 also has a unique digital depth-of-field preview built into the power ring that surrounds the shutter button. Just twist the power ring further to the right and the camera quickly stops down the lens to the selected setting and captures a quick shot to reveal the depth of field on the 2.5 inch LCD display. Quick and simple. The exposure is not stored, however, but disappears into digital ether.

The Pentax K100's body has a tight, solid feel, and all the doors seem like they'll stand up to reasonable use. Rather than a rubber door to cover the ports, which can actually be somewhat annoying to use, the Pentax K100D has a stiff plastic door that swings out toward the front. It is spring loaded and slams firmly open and shut. The SD card door works like most such doors, opening with a pull toward the back, then a swing to the right. The card pops out with a push.

The battery door on the K100D is locked with a small switch. You'll need to remember to turn the camera upside down before releasing the switch, because the door slides forward easily, and then it's free to swing open and dump your four AA batteries all over the place. It's worth noting here that the Pentax K100D didn't like most sets of our NiMH batteries, frequently complaining that a somewhat used set of four wasn't sufficient to continue. Not so with alkalines. A relatively new set of Energizer NiMH batteries does work fairly well, however, so I recommend a nice fresh set of NiMH batteries (or two) for the Pentax K100D.

Flash. The flash pops up quickly with the press of a button on the K100D, and it deploys automatically in Auto Pict mode, but only if the camera is set to Auto flash mode. That makes a lot more sense than most systems I've reviewed, where the full auto mode pops up the flash whether you like it or not. There is one instance where it would be good for the flash to pop up automatically, and that's when the AF system needs a little help, for pulsed flash is the K100D's sole AF assist lamp.

On-camera flash coverage is pretty good with the bundled 18-55mm lens, with only slight vignetting in the corners at the widest setting.

If you really want to impress yourself with what the K100 can do, however -- and overcome some of its indoor limitations, which I'll discuss later -- you'll want to consider investing in the large but versatile AF-540FGZ hot shoe-mounted flash. Folded up, it really is about as big as the Pentax K100D itself. Without going into great detail, it appears nearly as powerful as the flashes from Nikon and Canon, and its controls are more accessible, with commonly used features like first and second curtain sync and high speed sync available via a switch rather than a menu selection. You can also easily switch between a test pulse flash when pressing the Test button or a rapid pulse to serve as a modeling light. I even like how the flash attaches, with a quick, positive 120 degree turn of a large thumb-actuated lock, rather than a knurled ring that requires many turns.

The AF-540FGZ's head zooms with the lenses, and turns in almost every direction. There is no lock to hold it in forward position, however; the one button on the side of the Pentax K100D merely allows the flash to tilt down for better close-up coverage. Perhaps most impressive is the massive and wide AF-assist pattern the flash throws on the scene. I imagine all eleven sensors could take advantage of that baby.

Lenses. What keeps turning my head in the Pentax lineup are its unique and well-built lenses. The 18-55mm that comes with the K100D bundle is a decent lens, but I'm more impressed with its build than its optical quality. Unlike some kit lenses, the lens on this camera is appears of decent quality. It has a non-rotating front element and while it does whine when focusing, it's still mostly demure about it. The zoom ring provides both a good gripping surface and a soft touch, and the mechanism is tight. The front focusing ring has the slightest looseness, but it's not bad. And there are markings for both zoom and focus distance on the rings, another Pentax touch I can appreciate.

More than any other company, Pentax seems to have worked hard to create truly innovative lens designs that deliver the advantage of digital that others have mostly only promised. I'm talking about smaller lenses that fit into tight spaces. Pentax has some gorgeous little "pancake" lenses that are so small and flat that they make the overall camera look like something's missing. What they give you, however, is an SLR that can slip into a purse or coat pocket with considerably greater ease than any other design. They also deliver excellent optical performance such that when I shoot with these cameras, except for the purpose of evaluating this kit combo, I prefer prime optics like the silver 43mm Limited Edition f/1.9. Its external focusing ring is very fast and rips to its destination with a loud but sure ring of the focusing motor. Its soft silver anodize is etched with a sans serif font that harks back to the days of a fine rangefinder. It even has a manual aperture ring. Oh baby.

As if that weren't enough, the inside of the lens hood is lined with a photon-slurping fine black felt, and the metal lens cap is lined with a fine green felt, which not only looks refined, but serves to hold the cap onto the lens hood with a gentle pressure. It's design like this that can put the sense of precision, and even love, back into photography. I love this lens.

I have not yet seen a Pentax lens that feels cheap. They're all pretty small, very tight and solid, and sound like precision tools when they're attached and removed, probably due to the six springloaded contact bearings on the camera body's lens mount.

Unless you're prime-crazy like me (prime means single-focal length lenses, or non-zoom), the first lens you'll want to add to your Pentax K100D's camera bag is the 50-200mm f/4-5.6. Incorporating ED elements (extra-low dispersion glass), this short, lightweight lens again delivers on the promise of smaller lenses to match a smaller sensor. Its action is as smooth and high quality as the kit lens, and its optical performance seems good. Certainly impressive for its reasonable $250 street price. And it keeps the K100D reasonably compact. Like the other lenses in the line, the 50-200mm has a loud focus motor, but it's at least smooth and fast.

And Shake Reduction for all. Body-based stabilization--the main feature distinguishing the K100D from the K110D--means that all lenses that will fit on the K100D will benefit from this helpful technology.

Each company has had to create their own version of anti-shake, and each has its own name for its particular version. Canon's Image Stabilization (IS), Nikon's Vibration Reduction (VR), and Konica Minolta/Sony's Anti-Shake (AS) are now joined by Pentax's own Shake Reduction (SR). Nikon and Canon's are lens-based solutions, which means you have to purchase a specially-engineered lens to take advantage of the technology in each focal length range you think you need the extra help. With lens-based systems, the lens tracks the camera's motion and compensates for it by moving a special optical element inside the lens body.

Sony's solution is like Pentax's, which also tracks the camera's motion, but moves the imaging sensor inside the camera body to match. It's a little more like the catcher moving his mitt to meet the ball, rather than some elaborate mechanism that tries to redirect the ball to the mitt as it approaches the plate. Both work just fine in practice, however, despite what the baseball analogy might imply, and both have their benefits. We're of the opinion that lens-based solutions will do better with long telephoto lenses, and camera-based solutions are better for wide and mid-telephoto applications.

Nevertheless, when Pentax's SR system is used with their modern line of electronic lenses, the camera can detect what lens is attached and adjust the magnitude of compensation applied to match the focal length of the lens. When you're using an older lens, you can use the K100D's menu to tell the camera the focal length, from 8mm to 800mm.

Having used all current stabilization methods, the K100D's Shake Reduction impressed me. There were fewer blurred shots, with good performance all the way down to 1/13 second. Pentax says that its Shake Reduction Technology allows stable shots at 2.5 to 3 stops lower than with the feature switched off. Unlike Sony's solution, there is no display inside the K100D to tell you how hard the stabilizer mechanism is working based on your current motion, nor do you have the visual "floating image" feedback you get from optical image stabilizers. Instead, the camera compensates for the motion it detects when you trip the shutter.

There's a good argument that the moment of capture produces the most common and relevant source of motion blur in images, because so many people seem to mash down the shutter and shake the camera with it. It's why only some soldiers make marksman: it takes training, discipline, and a special character to learn to squeeze that trigger gently and let the shot surprise you every time. Camera companies have been trying to figure out how to help people with the moment of capture for a long time, and Pentax may have hit on the better body-based solution.

They claim that their SR system is different from others because it not only compensates for up/down/left/right/diagonal motion, but rotational motion as well.

After all, what happens when someone mashes down on the shutter release with their right finger? The camera rotates clockwise and down. It might even rotate back before the shutter closes, depending on the button masher in question and the shutter speed. A camera that can compensate for this very common motion as the shutter trips is likely to deliver more clear shots to the rank amateur, as well as compensate for the intermediate photographer's occasional excitement over capturing a promising moment. Regardless of the motion's cause, human motion is rarely linear or occurring along rigid x and y axes, so the more methods of compensation the better.

Autofocus. Our lab autofocus times are decent, but not stellar, with a full AF shutter lag of 0.182 second. But that's an average, and once it's relatively close, if the camera does not seek, this number is often faster than you'll get with real-life subjects that are at random distances. In low light, it gets worse. On the plus side, the Pentax K100D will keep trying to achieve focus. On the negative side it can take a second or two for the camera to run through its thought process and get the job done. Sometimes you can just feel the wheels spinning as the K100D tries first this setting, thinks about it, then tries another, thinks about it some more, then tries again and finally beeps confirmation. In sunlight, it's much better and feels quite a bit faster.

Also like most of the lenses for the Sony A100, the Pentax K100D's AF motor is in the camera body, not the lenses.

The new SAFOX VIII AF system has 11 focus points, nine of which are cross type, meaning they can sense both horizontal and vertical lines. Most AF systems reserve the cross type sensors for the center and outer edges.

White Balance. Admittedly, setting White balance automatically is quite a trick, but the K100D also struggles with setting white balance in low light, especially with Tungsten light sources. After an extremely great day out with the camera in daylight, I was surprised when I tried to take a low light shot of my toddler sleeping. He looked yellow. I grabbed another SLR that I'd brought along to capture some of these product shots and took the same picture. No problem. Not yellow, and his white shirt was just about right. In this case, the light wasn't Tungsten, but sunlight filtering through beige miniblinds. When I popped up the flash on the Pentax K100 and tried again, I got what you see below, much better. Later tests with Tungsten lighting, including our indoor lab shots, revealed a serious problem balancing yellow light sources. The resulting images are tough to rescue from this yellow cast.

Which brings me back to that camera-mounted flash. Give the K100D a good bounced light source and it's a dream. Attach something like a Lumiquest 80/20 bounce reflector to it, and you'll be blown away. You can also just pop up the built-in flash and get what you need, or else remember to switch to manual or Tungsten white balance before shooting indoors (what a pain). I'm hoping Pentax can fix this with software, but it seems somewhat unlikely. Be warned that though I'm very fond of the K100D, I compensate by using flash when shooting indoors, which isn't always ideal. Using the AF-540FGZ gives the best results, but it doubles the size and weight of the camera and requires more effort to find white surfaces to bounce the flash from.

Filters. The Pentax K100D also has a very good interface for accessing the Digital Filter functions, which allow you to set things like Sepia or Black and White after capture. A new image is created with each applied filter. If you watch the animation at right, you'll see it step through quite an array of color filters as well, one a light filter, and the other a darker filter of the same tint. You use the left and right navigator buttons to choose your image, the up and down arrows to choose among your filter options, and the main dial on the back to apply optional settings, like the multi-color filters and brightness changes. The Slim filter can also make you or your relatives feel better about your camera choice when instead of adding 10 pounds, the K100D takes away 10 or 20.

Summary. As I mentioned at the beginning, the Pentax K100D was enjoyable to use. It looks great, handles well, and delivers images that exceed what I have seen from the company's other digital SLRs. The included lens is very good, and the available accessory lenses are terribly cool. Tungsten white balance, unfortunately, doesn't cut it as well as it should. Our lab test results show the same problem as my own extensive informal shooting reveals: the K100D just can't compensate for Tungsten lighting, delivering extremely yellow images. Flash does fix it, so if you're happy carrying a big bounce flash, or dealing with the specular highlights often generated by direct flash, it's not a big deal. For serious indoor photography, controlling the light is arguably the way to go, so I do recommend purchase of a hot shoe-mounted flash.

My only other bugaboo with the K100D was its often slow and indecisive AF in low light. Low light means typical room lighting indoors. I've never seen a camera play for so long to finally lock focus. Pop up the flash as AF assist, and things speed back up. Just an FYI, not a deal killer; though if you're doing a lot of toddler photography, get a flash.

The K100D's Shake Reduction works very well, and is probably worth the extra $100 if you can afford it over the K110D. Once again, in low light, you need all the help you can get. I got sharp images at 1/13 second, which really surprised me.

The Pentax K100D is priced pretty low for what you get, but I think prices will need to drop before the end-of-the-year holidays to keep ahead of some of the older cameras still on the market, like the Nikon D50 and Canon Rebel XT. Online prices have dropped quite a bit on these two cameras over the last few months. Neither offers shake reduction, though; and their prices in retail stores will probably still be higher than the Pentax K100D at the outset.

It's good to see Pentax come out swinging, offering a tight, affordable camera for consumers. For my part, I'm still rubbing my chin about the concept of the K100D with a 43mm or 40mm prime lens for daily carry in a waistpack, chucking the point-and-shoot digicam in favor of a larger sensor and higher quality optics, not to mention the ease of AA batteries. Now that this review is over, I'm going to twist that silver Pentax FA 43mm Limited lens back on and test my theory until they make me return it.

Basic Features

• 6.1-megapixel CCD
• Pentax K AF bayonet lens mount compatible with the full range of Pentax K lenses, plus M-series lenses via an adapter
• Digital SLR design with true optical viewfinder
• 2.5-inch color LCD monitor for image and menu review
• Full Manual through Automatic exposure available, including Aperture and Shutter priority and 14 preset Scene modes
• Built-in flash with five modes and an intensity adjustment
• Topside external flash hot shoe
• SD/MMC memory storage (no card included)
• JPEG and RAW file formats
• USB 2.0 computer connection
• Two CR-V3 or four AA-type batteries for power, or optional AC adapter (four AA alkaline batteries included)
• Software for Mac and PC

Special Features

• Shake Reduction technology to minimize blurring from camera movement
• Digital filter options for creative effects post-capture
• Continuous shooting mode and Auto Exposure Bracketing
• Self-timer for delayed shutter release
• Optional remote control (wired and IR)
• Shutter speeds from 1/4,000 to 30 seconds, plus a Bulb setting for long exposures
• Image Sharpness, Saturation, and Contrast adjustments
• Spot, Center-Weighted, and Multi-Metering modes
• Adjustable AF area and two AF modes
• Auto ISO setting or 200, 400, 800, 1,600, and 3,200 ISO equivalents
• White balance (color) adjustment with 10 options, including a manual setting
• Adobe RGB and sRGB color space options.
• 18 Custom Menu settings, including options for non-CPU Pentax lenses
• DPOF (Digital Print Order Format) and PictBridge printing compatibility

In the Box

The retail package contains the following items:

• Pentax K100D digital camera body with body cap
• Pentax 18-55mm lens (if purchased as a kit)
• Shoulder strap
• Four AA alkaline batteries
• Flash hot shoe and eyepiece covers
• USB cable
• Video cable
• Software CD containing Pentax Photo Browser and Laboratory software, and USB drivers.
• Manuals and registration information

Recommended Accessories

• Two sets of four rechargeable NiMH batteries. (Read my NiMH battery shootout page to see which batteries currently on the market are the best, read Dave's review of the Maha C-204W NiMH battery charger, our current favorite.)
• Large capacity SD/MMC memory card. (These days, 512MB is a good tradeoff between cost and capacity.)

Conclusion

The Pentax K100D is a capable digital SLR, perfect for consumers interested in stepping up from a basic consumer digital camera and into a world of better image quality. It's also a smart choice for owners of Pentax film SLRs and lenses who want to go digital. With its full range of manual and preset automatic exposure modes, the Pentax K100D is suitable for the full range of experience levels, including anyone already owning a digital point-and-shoot, and it offers enough customization to keep more advanced users happy. The Pentax K100D has no trouble with exposure in low lighting, and produces only slightly high contrast under harsh lighting conditions (such as bright outdoor sunlight). Autofocus in low light is among the slowest we've seen, however. On the positive side, though the K100D more often makes a decision where other digital SLRs just give up. Color is quite good, though sometimes on the warm side, but both the built-in flash and accessory bounce flash eliminate this problem. The camera's ISO setting only goes as low as 200, but noise levels are still quite good, and prints from the Pentax K100D are very impressive even at the highest ISO levels.

We were impressed with the Pentax K100D, as well as its widening array of accessories and lenses. It's a small, well-conceived SLR design with solid image performance. Even the kit lens is good quality, and accessory lenses are worthy of serious photographic work. After all that, the Pentax K100D's in-camera Shake Reduction is a welcome bonus in this surprisingly low-priced camera. Perhaps the best news is that it works better than most other in-body anti-shake systems on the market. Despite its shortcomings, the Pentax K100D offers more bang for the buck than competing systems in this range, and the money you save on the kit leaves room to pick up an accessory flash to make indoor photography a dream. Overall, the K100D is Pentax's strongest offering to date. It's a camera I've really enjoyed, and worthy of a Dave's Pick.