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
The new Prynt Pocket can print a photo directly from their iPhone simply by inserting the phone into the printer, then snapping a photo. Each print will cost about 50 cents. Read more
Updates for Adobe Camera Raw and Lightroom CC bring support for the Sony Alpha 9 and Panasonic ZS70/TZ90, along with bug fixes.
After the makers of the Triggertrap remote camera control system is no longer sold due to the company folding, users will be able to build their own, as the hardware design has been released to the public.
The Magic Format Converter comes with internal optics that expand the image circle of full-frame DSLR lenses for use on the Fuji medium format camera. Read more
The usually Apple-exclusive MacPhun software developer has announced that it will introduce PC versions of two of its most popular applications. Both Aurora HDR and Luminar should be available for the Windows operating system by the autumn of this year. Read more
Sony's newest G Master telephoto zoom, announced alongside the a9, is the first of the company's FE lenses to reach 400mm natively. We had one in California and photographed horses, portraits, and landscapes - check out how it did. Read more
Garmin has entered the 360-camera market with the VIRB, which captures 5.7K video at 30p as well as 15MP stills. Read more
German media reports that the founders of the company behind the Panono 360-degree ball camera have filed for bankruptcy at a court in Berlin. Read more
With a claimed 800 new custom parts, Microsoft's updated Surface Pro comes with the latest Kaby Lake processors, better battery life, a new hinge, plus the Surface Pen is updated as well. Read more
DW Photo is attempting to resurrect the Hy6 medium format camera, though the legal tangles of its development may stop it being branded Rolleiflex.
The Kodak EKTRA, the company's 'camera first' smartphone, is now available to purchase in the United States. Read more
Apple and Nokia have settled their years-old patent dispute. Apple will make an undisclosed payment to Nokia and sign a licensing agreement related to digital health products with the Finnish company.
David Gibson, one of Britain's best known street shooters, shares all.
Photographers from the SKYGLOW project travelled 150k miles and took 3 million photos in increasingly rare locations: those without light pollution.
The world's fastest 200mm was produced for 16 years. In that time, only 8000 were made.
Photokina, the biennial photo industry trade show in Cologne, Germany, has announced that it will become an annual event beginning in 2018, and expand its focus to additional areas of imaging technology. Read more
No mic socket? No problem. In this video, Daniel Peters at Photo Gear News shows you how to make a lapel microphone using just a smartphone and a pair of earbuds.
How does the iPhone 7 Plus stack up against the Arri Alexa cinema camera? Watch this short video to find out.
Canon Australia's video series "The Lab" is designed to make photographers experiment and think outside the box. In the latest video a group of photographers create images based on their sense of taste.
The GH5 is expected to get a firmware update this summer to support 400Mbps internal recording. NewsShooter explores what memory cards you'll need to make it work.
Microsoft's new Surface Pro offers Intel's latest processor generation and improved battery life.
Riding a mountain bike downhill is dangerous enough in daylight, but potentially lethal at night. Which is where drones come in.
Rumors abound that Canon (and maybe Nikon) may produce a mirrorless camera based using their existing DSLR mount. Does this guarantee immediate great lens choice or a perpetually second-rate experience? Read more
According to rumors, the next camera from Nest will be able to capture 4K video, though that resolution will be only used for 'virtual' pan and tilt functions.
Boundary's Prima 'fully modular' backpack is expandable to 30L and has a removable camera case and tablet sleeve. Early Kickstarter backers can get one for $189.
Stanley Greene captured 'brutally honest' photographs in the war zones of the Middle East, Chechnya and Georgia. He was also one of the few African-American photographers working internationally.
Owners of Leica M cameras that suffer from peeling CCDs will be able to claim a free repair in the future so long as the camera was purchased within five years of the fault becoming apparent, the company has announced. Read more
The Carl Zeiss Jena BIOTAR 75mm F1.5 Red T lens is very rare and priced accordingly. It can be yours today for the low, low price of $15,000.
The MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) has developed a drone that does not require any human control for recording tracking shots. Read more
In this terrifying video, Iraqi journalist Ammar Alwaely narrowly misses a sniper's bullet, which takes out his chest-mounted GoPro. Warning: strong language. Watch the video