Pentax K10D Review by Sean Carpenter

The Reviewer

I've been shooting with a Pentax for the past two years or so, and during that time have taken more than 60,000 photographs - 55,000 of them with a single Pentax *ist DS. I've embraced the technical and artistic aspects of photography, easily qualifying as an enthusiast. This review is intended towards like-minded enthusiasts, and while the opinions might be solely held by me I hope they help others come to their own conclusions. The images referenced in this review, some full-sized, can be found on my web site.

The Camera

Overall, the K10 is a larger and more substantial camera than its predecessors. The grip on the K10 is much thicker and more comfortable than on the *ist D, although the *ist DS was also an improvement in this regard. The K10 is wider, longer, and thicker than the *ist models, meaning that it is also heavier. While I thought that the *ist DS felt sturdier because of its diminutive size, the K10 to me still feels like a solid camera.

The overall speed compared to my *ist DS and especially to the *ist D is much improved in the K10. Playback review is nearly instantaneous, the K10 is capable of 3 frames per second, and in JPEG mode can shoot until the card is full without stopping. Similarly to the *ist models, there is also no perceptible shutter lag.

The K10, surprisingly, boasts weather and dust seals. This should be a welcome addition to anyone caught in the rain or living in the Pacific Northwest. I've had mine out in moderate-to-heavy rain several times already, with no ill effects so far.

Specifications courtesy of pentaxslr.com:
	Type:		- Auto-exposure digital SLR still camera with TTL auto focus, built-in retractable P-TTL auto flash, and CCD shift shake reduction and dust reduction
	Sensor:		- Interline interlace CCD with a primary color filter - 10.75 megapixels - 8 bit (JPEG) or 12 bit (RAW) x 3 colors
	Resolution (Recorded Pixels):		- JPEG: 10M(3872x2592 pixels), 6M(3008x2000 pixels), 2M(1824x1216 pixels) - RAW: 10M(3872x2592 pixels)
	ISO Sensitivity:		- ISO Auto, 100, 200, 400, 800, 1600
	File Formats:		- JPEG (Exif 2.21), RAW (PEF, DNG), DCF (Design rule for Camera File system), DPOF (Digital Print Order Format), PRINT Image Matching III
	Color Space:		- sRGB, Adobe RGB
	Lens Mount:		- PENTAX KAF2 mount compatible with PENTAX KAF2, KAF and KA mount lenses - Power zoom functions 1 and 2 available - K-mount lenses usable with restrictions - S-mount lenses usable with adapter and with restrictions - 67/645 lenses usable with adapter and with restrictions
	Focusing System:		- TTL phase-matching 11-point autofocus system (SAFOX VIII) - AF-Single (with focus lock), AF-Continuous, Manual - CCD Image Sensor Shift
	Exposure Control:		- TTL open-aperature metering with choice of: 16-segment, Center-weighted & Spot meter
	Click here to download the entire pdf specifications manual from pentaxslr.com.

Shortly after buying the K10, I purchased the matching vertical grip. The vertical grip vastly improved the overall feel of the camera, and in addition to offering capacity for an extra battery, portrait-oriented scroll wheels and shooting controls, it also made the 'normal' landscape grip more sturdy. As shown below, it does add both weight and bulk to the camera. While the controls on the portrait grip aren't as easy to press or use as on the camera itself, I highly recommend the grip to anyone considering this camera.

The K10D with battery grip, left, compared to the *ist DS, right.

The Controls

Pentax also implemented a useful 'Raw' button, which switches from shooting JPEGs to raw files without using a menu. I find this useful if I'm shooting casually in JPEGs and find a scene that presents difficult lighting conditions for which I want the flexibility of raw.

The Mode Dial

Since my primary concern when shooting is depth of field, I almost always shoot in Aperture Priority (Av) mode. In addition to controlling aperture, I usually fiddle with exposure compensation (Ev) and, if necessary, change the ISO.

Av mode on the K10 is nearly perfect for me. I have my front scroll wheel set to control my lens aperture and the rear scroll wheel to control exposure compensation. (The wheels are programmed via the custom menu.) This is a much better implementation than with my DS, where you must press-and-hold the Ev button while scrolling the single wheel. To change ISO, I still need to press the Fn button and select the appropriate ISO from the menu - there is no dedicated ISO button.

I was excited to try the Sensitivity Priority (Sv) mode, since this is one of my 'big three' variables when shooting. While Sv mode allows setting the ISO using one of the scroll wheels, I was disappointed to find out that the other scroll wheel cannot set the aperture. There is an option for the second scroll wheel in Sv mode to adjust 'Program Shift' which can change aperture or shutter depending on an algorithm designed by Pentax. While the Program Shift is a sort-of-aperture control, I still found it annoying when it changed the shutter instead of aperture, so I don't find Sv mode useful to my tastes.

The other new addition is 'Shutter & Aperture Priority' (TAv) mode. This mode sets shutter speed with one dial and aperture with the other, allowing the camera to choose the ISO within your desired 'Auto ISO' range. Since I rarely need to set the shutter and Auto ISO is already available in Av mode, I don't find TAv mode of much use either. So I'm back to shooting the same way, albeit more conveniently, than I did on my *ist DS - almost exclusively Aperture Priority mode.

A Note On Using Manual Lenses

I regularly cheer Pentax for its support for older, manual lenses. All of my favorite lenses were made well before my first DSLR purchase, so support for them is paramount. Despite what the official literature confusingly states, the K10 can be used with every Pentax lens produced in the last 40 years.

The K10 inherited the same glass pentaprism as in the *ist D and DS, making manual focus relatively simple. The pentaprism offers a larger view than on models with a pentamirror, such as the Pentax K100D or Nikon D40. The focus screen clearly identifies the focus area, and is much better than the Canon 20D/30D in this regard. The viewfinder has a diopter adjustment allowing calibration for fluctuations in eyesight.

Unfortunately, Pentax disables the scroll wheels when using these fully-manual lenses. This is unfortunate because the scroll wheels cannot control exposure compensation, which was one of my favorite features. Hopefully this is something Pentax can and will update via firmware.

While Sv mode is also disabled, the K10 does offer Auto-ISO with these old lenses.

The K10D with ca. 1974 Super-Multi-Coated Fish-Eye Takumar 17/4 lens.

Overall Impression - Using the K10D

The K10 is a solid camera, in build, ergonomics, and user interface. The camera is better overall than my *ist DS, with controls and layout even improved over the more 'pro' *ist D. The camera is heavier than its predecessors, in exchange for which it offers a more substantial grip and easier-to-access buttons and knobs.

It is worth noting that for the first time in a sub-$1,000 camera, the K10 offers weather sealing, in-body anti-shake, and a dust-resistant sensor. Coupled with the innovative (if not perfectly implemented) Sensitivity and Shutter & Aperture Priority modes, hopefully the K10 will fuel competition with the other camera manufacturers and bring more professional features to the consumer for less.

I took the K10 to the Pacific Northwest for a recent trip. 700 photographs and 6 full days later I was still shooting on a single charge. I will admit to being non-committal on the proprietary-versus-standard battery debate from the start. I don't like having yet another charger, but I'll accept the burden if it means a stronger, lighter battery.

Some Gems

Pentax did many small things right on the K10. Some of the more pleasant surprises I've found using my camera:

• The top LCD is illuminated by pressing the ± button.
• An RGB histogram is available when reviewing shots.
• Adjusting the white balance shows the last shot taken as the sample. This is an impressive improvement over typical manual white balance adjustments, and I find myself using the Kelvin white balance setting regularly.
• The scroll wheels are enabled in most menus as a page up/down or move up/down, making it quicker to navigate through long lists.
• There are infrared remote receivers on both the front (for self-portraits) and back (for long exposures and such) of the camera.
• When shooting in, RAW+JPEG mode either the RAW or the JPEG can be deleted individually. This is important if you want to enter the weekly shot number challenges but don't need to store another RAW shot of your hydrangea.
• JPEG 'development' from the RAW files in-camera. Yes, this was only to give a shot of my nephew to my sister, but it was still nice to be able to do.
• The K10 offers to save certain settings, like shooting mode (single/continuous/delay/remote) after turning off and on again the camera. This removes another step if you're shooting with the remote control but are waiting in between shots (for time lapse shots, perhaps?).
• ISO is selectable by 1/2 or 1/3 increments.

Some Nits

I've been overwhelmingly pleased with the usage of the K10, but as with any camera, I've stumbled across a few items that I don't like very much.

• On two separate occasions, my rear scroll wheel has stopped working - simultaneously on the camera and vertical grip. I've had to simply power off and on the camera to get it to recognize the wheel.
• The on-board flash cannot act as a wireless trigger to an external flash. This is a bit disappointing, since this feature was available in the *ist D.
• The lack of TTL flash support. See here for more on TTL support.
• After taking a shot, the scroll wheels zoom in to the picture. There are (too many) times when I take shots in succession at different apertures or exposures, and this feature forces me to interrupt my shooting to make the previous shot 'go away'.
• When selecting the shake reduction, I would prefer to use the scroll wheels. This is especially important when changing from 24mm to 300mm!
• I'd like to see the infrared remote capable of shooting in bulb mode without having to hold down the button the whole time. I'd rather have the first press open the shutter and the second one close it.

The Pictures

I reserved my opinion of the K10 mainly because I wanted to become more familiar with the pictures themselves. As intuitive and familiar as the physical camera was, the actual images it produced were foreign territory.

The ISO range on the K10 is 100-1600, rather than the 200-3200 on the 6MP Pentax models. Since I favor shallow depth of field, the lower ISO was welcome, although I haven't as yet found an opportunity where it matters. Conversely, I was tentative to lose ISO 3200, despite the fact that I haven't shot more than a handful at such high ISO. I finally decided that either implementation was fine with me, and I'll certainly get more usage at ISO 100 than I do at 3200, although whether all those ISO 100 shots would look fine at ISO 200 is another question.

The K10 offers two different raw formats, DNG and Pentax-proprietary PEF. I've been shooting PEF files in my DS for over a year, and to reduce space I've been converting them to (compressed) DNG as part of my workflow. Unfortunately, the K10's support for DNG hasn't saved a step in my workflow, since the DNG files are uncompressed as well. Note, however, that the Pentax PEF files are indeed compressed in the K10. Unfortunately, my raw converter of choice, Adobe Camera Raw, doesn't yet recognize the Pentax PEF Files, so I'm still shooting raw (in DNG format) and running them through the converter to compress them. Decision made, more so by my raw converter than anything else.

The K10 offers temperature selection for white balance. On previous models, there is a 'Custom' setting for white balance but given how fickle it is, I didn't use it much. Shooting in raw removes the need for white balance anyway. But if I could accurately and easily set the white balance I might be tempted to shoot JPEGs more often, especially on long trips where space is at a minimum.

Finally, there are 10 million pixels on the K10's sensor. What impact (besides obviously that the files are physically bigger) would this have on the pictures themselves? How should I even start to evaluate or compare them? I'll start by showing some images!

The Pictures - Capturing Detail

Surely part of the 'megapixel race' is a hunt for more and more detail in digital photographs. Does the K10, with 4 million more pixels than the *ist DS, produce more detail? Yes, it does. Is it significant? Not for me, and probably not for you.

Comparing Detail

To quickly show this, I shot the same scene (a Pellegrino bottle on a table) with both the K10 and the DS using the same smc Pentax-D FA 100mm f/2.8 Macro lens. As with all of my testing shots, both cameras were manually focused, mounted on the same tripod, using the wireless remote. Both were shot in raw (the K10 in DNG, the DS in PEF) and converted to 8-bit JPEG in Photoshop CS2. The scene is represented below:

*ist DS, SMC Pentax-D FA 100/2.8 Macro, f/8, 1/3s, ISO 200

Taking a crop from the center of the image and enlarging the DS to the same resolution as the K10 yields the following full-size comparison:

Without applying any sharpening, there appears to be more detail in the K10 shot on the right, and both look respectable.

But what are we looking at? Assuming your screen resolution is the same as mine - 96dpi - the image above would be the center of a 27" x 40" print! In other words, the above resolution is virtually meaningless to almost all of us.

Reducing the crops down to a still-large 13" x 20" (or so) and applying some mild unsharp mask in Photoshop yields the following results:

The advantage is still there for the K10D, but it is mild. At 800 x 533 pixels for web viewing, there is no discernable difference between the 6 and 10 megapixel images.

Raw Detail vs. JPEG Detail

Are the K10D JPEGs 'soft'? Without owning a competing camera, I'm not going to be able to compare to the Nikon D80 or Sony alpha 100, but what I can do is show the JPEG and raw images from the same shot. The shot below was cropped from the JPEG and DNG raw exactly the same, then saved as 11-quality JPEGs. No sharpening or contrast curve was applied to either shot.

The Pictures - ISO Noise

Without being an expert on chroma, luminance, or per-pixel noise, my initial impression was that the K10 pictures seemed 'more noisy' at equivalent ISO to ones from the *ist DS. Now I'm sure that there are two distinct issues - one that I'm solving on my own and one that hopefully Pentax will address.

Combating Noise

The one that I'm solving has to do with noise at default settings, which to my tastes are too high. At sensitivities greater than ISO 400, for example, an underexposed JPEG produces areas of splotchy color in the shadows. Especially in difficult lighting conditions, the K10 produces noticeable magenta spots. The same conditions are replicated when shooting raw and opening the files in Adobe Camera Raw using the default color settings.

In adjusting the color calibration settings to get more accurate colors, I noticed that it simultaneously reduced the apparent noise. This was a wonderful side effect! I can now get my shots to have more accurate colors and less noise simply by adjusting the hue and saturation individually. This also gives me hope that once Adobe fully supports the K10, including the PEF files, that the colors will be more accurate and the noise reduced.

As an example, I took some shots of my favorite electrical fan.

The settings for the shot above still need more fine tuning, and obviously individual monitor/printer settings should impact the color as well. My monitor is calibrated slightly redder than 'true' color to match the output from my local print shop, but everyone's monitor/printer is going to be different.

The encouraging thing for me is that despite the work involved in managing color hue and saturation for each color for each image, I believe that future updates to Adobe Camera Raw will address this by default. Hopefully getting the correct color (and lower percieved noise) will be similarly easy as it was on the 6-megapixel models.

Patterned Noise

The second image quality issue concerns vertical patterned noise ("banding") that is especially noticeable in shadows at high ISO. I have images displaying clear bands of noise in the shadows, even in the highlights if slightly underexposed, and without extensive re-touching can not fix the problem. I have hope, based on this thread that Pentax can and will address this in a firmware update.

The Pictures - The Rest of the Story

Certainly there are other aspects to the photographs besides resolution and noise. Some factors to consider in any system are white balance, dynamic range, purple fringing, dust removal, and shake reduction.

White Balance

Dynamic Range

The dynamic range, or ability to accurately capture color and detail from dark to light, can sometime be frustrating. I haven't noticed either an increase or decrease from my DS, although I have noticed that the default exposure on the K10 is slightly higher. Whereas on the DS a photo might be slightly underexposed to keep details in the highlights, I find the K10 will 'blow' the highlights to keep the remainder of the photo properly exposed. Since the exposure in general has been very consistent with the K10, dialing in negative exposure compensation accounts for the highlights. The K10, in exposure just as in white balance, provides a consistent and usable way to override the automatic settings.

Purple Fringing

After doing side-by-side tests with identical lenses, I have found absolutely no increase in purple fringing with the K10. Indeed, with my well-corrected lenses, I don't see purple fringing even in difficult scenarios.

Dust Removal

Dust, showing up as annoying darkened spots, present another challenge to digital photography. The K10 has several features to combat dust on the sensor: an anti-static coating on the sensor, a dust-collecting strip below the sensor, and a sensor-shaking dust reducer. My K10 does in fact have a few dust spots on it, and one pass of the sensor shaking has not removed them. However, I am hopeful that the anti-static coating will reduce incidence of dust and also that the dust-collecting strip will help when using a hand blower to manually clean the dust.

Shake Reduction

Lastly, the K10 has a much-advertised shake reduction. I've used similar anti-shake technology in the Konica-Minolta 7D, and frankly never thought much of it. The Pentax implementation is a bit more novel than the Minolta one, in that the Pentax sensor 'floats' on magnets, allowing compensation for rotational as well as linear (up and down) motion.

Anti-shake has many proponents, and it undeniably works - sometimes. My problem with anti-shake is that by its very nature there is no manual override. If I get a blurry picture with anti-shake turned on, was it simply that I moved too much, that my subject moved, or that the anti-shake over- or under-compensated for my motion? Honestly, I'd rather simply invest in faster lenses and turn anti-shake off. Additionally, I rarely shoot lenses longer than 135mm, so the K10's anti-shake is really a non-feature for me.

My Conclusion

When the specifications for the K10D were first released, I was enthused. It appeared that Pentax went point-by-point through my list of complaints about my *ist DS and addressed them, making this upgrade and obvious choice.

My initial reaction after getting the camera, however, was one of disappointment. The camera physically far exceeded my expectations, and was laced with ingenious features on top of a very intuitive interface. It was the sensor, specifically the performance of the sensor over ISO 400, that surprised me. My rainy first week of use was dreary and dark, and indeed my opinion of the K10's sensor matched the weather perfectly.

The Pentax K10D is a thoroughly usable camera. The true pentaprism viewfinder offers a big, bright, clear view. The grip is comfortable, adding the optional vertical grip makes it even better, and the increased weight (compared to the *ist series) is noticeable but acceptable. The controls are well-laid out and the menus are intuitive and easy to navigate. The rear LCD screen is big and bright, with a decent viewing angle. Everything the camera does, from taking shots to reviewing and deleting them, is so fast as to be nearly instantaneous. And, perhaps most importantly, it has the terrific K mount.

The K10 is a camera that has ingeneous solutions. From the Pentax-standard Hyper-Program, to the new Sensitivity or Shutter & Aperture Priority modes, it is clear that Pentax is proud of innovation. It also seems that Pentax designs its cameras with its user base in mind, making cameras that are instantly comfortable and usable.

Most images at low ISO are going to be brilliant, either raw or JPEG. The excellent custom white balance has me shooting JPEGs comfortably. For difficult lighting or high-ISO shots, I'm shooting raw and investing the time fine-tuning the results. My auto-ISO settings are now 100 through 1000, which is quite a step up from my first few weeks with the camera.

I wouldn't hesitate to recommend the K10D, based on its ergonomics alone. It certainly takes some effort to realize the full potential of the images, especially at high ISO sensitivity. The rewards of the K10D are many, and many more with some time and effort - as is anything worth having in life.

Content copyright © 2007 Sean Carpenter, for PentaxForums.com. All rights reserved. Unathorized display of this review is prohibited. PentaxForums.com Home