Pentax K10D Review
Our new Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from (the cameras) black to clipped white (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).
To most people highlight range is the first thing they think about when talking about dynamic range, that is the amount of highlight detail the camera can capture before it clips to white. Shadow range is more complicated, in our test we stop measuring values below middle gray as soon as the luminance value drops below our defined 'black point' (about 2% luminance) or the signal-to-noise ratio drops below a predefined value (where shadow detail would be swamped by noise), whichever comes first.
Image Tone setting
The K10D provides two selectable image tones which define the tone curve and color saturation. The default Natural and optional Bright tones deliver the same amount of dynamic range, albeit with a slightly different tone curve.
In addition to the image tone options there are also obviously a range of image parameters which can be adjusted, only Contrast would affect the final image dynamic range. Here we have tested the extremes of the contrast setting from -3 to +3. In the shadow region (below middle gray) we see that the -3 setting delivers more shadow information before our cut-off point, and as we would expect the +3 setting the opposite. No setting changed the amount of highlight range (that above middle gray) which always clipped at around 2.8 EV.
The K10D had a very strange, contrasty tone curve, a virtual straight line from middle gray upwards with almost no roll-off in highlights and (just like the K100D) a lower than average highlight range (about a third of a stop less than the competition). At higher sensitivities the total range becomes limited by the amount of noise at the darker end of the range (shadow range).
|Sensitivity||Shadow range||Highlight range||Usable range|
|ISO 100||-4.5 EV||2.8 EV||7.3 EV|
|ISO 200||-4.5 EV||2.8 EV||7.3 EV|
|ISO 400||-4.4 EV||2.8 EV||7.2 EV|
|ISO 800||-4.0 EV||2.8 EV||6.8 EV|
|ISO 1600||-3.7 EV||2.8 EV||6.5 EV|
Dynamic Range compared
Again the K10D's contrasty tone curve is even more obvious here, giving up around a third of a stop in shadow range and a third of a stop in highlight range it actually delivers less dynamic range than we were expecting to see (obviously you could use a lower contrast setting to compensate, although this would only gain shadow range).
|Camera (ISO 100)||
|Pentax K10D||-4.5 EV||2.8 EV||7.3 EV|
|Nikon D80||-4.8 EV||3.2 EV||8.0 EV|
|Sony DSLR-A100||-4.8 EV||3.3 EV||8.1 EV|
|Canon EOS 30D||-5.1 EV||3.3 EV||8.4 EV|
The wedges below are created by our measurement system from the values read from the step wedge, the red lines indicate approximate shadow and highlight range (the dotted line indicating middle gray).
Experience has told us that there is typically around 1 EV (one stop) of extra information available at the highlight end in RAW files and that a negative digital exposure compensation when converting such files can recover detail lost to over-exposure. As with previous reviews we settled on Adobe Camera RAW for conversion to retrieve the maximum dynamic range from our test shots.
As you can see from the graph below the Adobe Camera RAW default is actually quite similar to the camera JPEG, if anything there's very slightly more highlight range. The best we could achieve (with some pretty extreme ACR settings) was just over 10 stops total dynamic range, and more importantly about a stop more highlight range (although with no guarantee of color accuracy in highlights).
- ACR Default: Exp. 0.0 EV, Shadows 5, Bright. 50, Contrast 25, Curve Medium (Default)
- ACR Best: Exp. -0.85 EV, Shadows 0, Bright. 70, Contrast -25, Curve Linear
WARNING: One thing to bear in mind is that although ACR was able to retrieve the 'luminance' (brightness) of wedge steps which were previously clipped there's no guarantee of color accuracy as individual channels may clip before others. This can be seen fairly clearly in the examples below, on the right the negative digital exposure compensation has revealed some more detail in the sky but there is no color information so the sky suddenly turns from cyan to gray.
|ACR default conversion||ACR with -1.25 EV digital exp. comp.|
Dec 15, 2006
Sep 13, 2006
Dec 9, 2009
Dec 11, 2009
A Federal judge has refused to throw out a copyright case against controversial artist Richard Prince, who used an image by photographer Donald Graham in an exhibition.
Sony has teased its customers with news of an upcoming announcement: it will soon take the wraps off a new CineAlta motion picture camera, one sporting a 36x24mm sensor.
QuikStories is integrated into the latest version of the GoPro app and automatically creates 'stories' using the video clips you've shot during a day.
Journalists photographing a protest in the US Capitol building claim they were told by Capitol Police to delete photos and videos of arrests.
The Meizu Pro 7 Plus secondary display can be used for music playback, date and weather-related information, or as viewfinder when taking selfies with the rear cameras.
Nikon is marking its 100th anniversary in many ways, including the creation of a new scholarship program for 'future visual creators' in the USA and Canada.
Take one Digital ELPH (or IXUS), rotate it vertically, add a fully articulating LCD and a lens with a camcorder-like focal length, and what do you get? Why, the Canon PowerShot TX1, of course. In this week's Throwback Thursday we revisit Canon's one-of-a-kind hybrid stills/video camera.
Just in case there was any doubt in your mind, here's the definitive video proof that yes, a $50,000 cinema camera beats the pants off a $50 camcorder in a side-by-side test.
Photographers who fly frequently in the US may want to finally invest in that TSA Pre-check status: in standard security lines, cameras and all other electronics larger than a smartphone will need to be placed in a separate bin for screening.
Images have appeared which claim to show Nikon's forthcoming D850 DSLR, the development of which was announced this week. If genuine, the pictures indicate that the D850 will offer illuminated controls and a tilting LCD screen, but no built-in flash.
To celebrate the Daguerreotype Achromat 2.9/64 lens' successful Kickstarter campaign, Lomography has announced a chrome-plated version of the lens in Nikon and Canon DSLR mounts.
Nikon just released four new firmware updates, adding features and fixing bugs in the D600, D610, D750 and the KeyMission 80.
It probably hasn't made your landscape photography bucket list just yet, but there's a good reason to visit Idaho. Here are 9 must-visit locations in this beautiful state.
Oops... Adobe accidentally leaked their unfinished Lightroom-powered cloud-based photo editor 'Project Nimbus' to some Creative Cloud users yesterday.
Storm chaser and award-winning photographer Mike Oblinski just released his latest time-lapse, and it is absolutely stunning.
Looking to level up your video capture capabilities without buying a whole new camera? Blackmagic's Video Assist 4K is well worth considering, despite a few flaws and its lack of 4K/60p support.
We're big fans of Fujifilm's fast-growing GFX system, and the GF 110mm F2 lens is no exception. Positioned as the system's classic portrait lens, its optics are just as impressive with non-human subjects as well.
Nikon turns 100 years old today, and the company is celebrating with a wacky music video, some tributes to its history, and a new vision presented by president Kazuo Ushida.
Phottix just released the Premio Parabolic Umbrellas series, replacing their Para-Pro line with a stronger, deeper and better made set of parabolic umbrellas.
The Moto Z2 is Motorola's first dual-camera smartphone and, compared to its predecessor, comes with a number of improvements and new camera features.
Researchers at Stanford have revealed a new '4D camera system' built for robots. The system is based on the same light field tech that allowed Lytro cameras to refocus images after they were taken.
If you want 'beautiful rendition' from your lenses, follow this simple rule: only buy classic low-element prime lenses with lead glass elements—everything else is junk.
In an interview with CNBC, Leica Chairman Andreas Kaufmann said he dreams of a 'true Leica phone,' and hinted at what's next for the Leica and Huawei partnership.
Wildlife and nature photographer Peter Mather tells the story behind this exceptional shot of a mama grizzly and her cub searching for salmon in Yukon, Canada.
Popular YouTube channel TastyTuts has put together this 33-video Beginner's Guide to Adobe Photoshop—a godsend for anybody who wants to learn Photoshop from scratch.
The long anticipated replacement for the popular Rode VideoMic Pro is almost ready for shipping. The price of the upgraded VideoMic Pro+ will be £290/$300 when it goes on sale in mid-August.
A new iOS app called Explorest wants to help you find new locations to shoot. It's limited to Singapore for now, but the app is packed full of useful location scouting features.
Nikon's D850 development announcement is extremely light on details, so we assembled a wish list of upgrades and features we'd love to see.
Nikon has announced the development of the long-awaited replacement to its full-frame D810: the D850. Nikon says that the D850 will build on the strengths of its predecessor and offer 'new technologies, features and performance enhancements.'
Lens manufacturer Voigtlander has introduced a 65mm F2 macro lens for Sony E-mount that it says "rates as one of the finest in the history of Voigtländer."