As discussed in the Launch Announcement just before PMA, the Pentax K20D is now surprisingly the highest resolution Digital SLR in its class of prosumer DSLRs. That statement doesn't really convey the real comparison since the only current camera with higher resolution than the 14.6 MP (megapixel) K20D is the $8000 Canon 1Ds III with a full-frame 21.1 MP image.



The Pentax K20D has the highest resolution available in an APS-C sensor SLR. It is 20% higher resolution than the new Sony A700/Nikon D300 Sony sensor pair at 12.2 MP and almost 50% higher than the Canon 40D. Those are numbers that are hard to ignore.

Those who wondered why Pentax entered into a partnership with Samsung a few years ago finally have their answer. Samsung wanted to play in the high-end sensor market with Sony and Panasonic; their partnership with Pentax was to develop sensors for the digital SLR market. We don't know details yet, but we have to guess the Hoya merger also plays into this scenario since Hoya is the world's largest maker of optical glass. You would be surprised to see a list of companies who buy their lens glass from Hoya (THK).

There is no disputing the fact that the Pentax K20D is now the highest resolution prosumer DSLR; however, everyone has learned that sensor resolution is not the only thing that matters in image quality. As the high-resolution but tiny point-and-shoot sensors have proved, a higher resolution is not necessarily better.

Pentax addressed this concern when the K20D was announced. By reducing the area between pixels, Samsung/Pentax claimed the sensor design used larger pixels that are the same size as 12 MP designs. If this is true, the image quality of the K20D should be spectacular.



The sensor is also CMOS like the pioneering CMOS sensors of Canon and the architecture of the latest Sony/Nikon/Olympus sensors. In fact, all the recent top sensors have been CMOS, relegating 10 MP CCDs to low-end to midrange models. The lone exception is the announced Sony A350, which will sport a 14.2 MP CCD sensor.

For all of these reasons we couldn't wait to get our hands on a K20D just as soon as they were available. The K20D is finally shipping, and over the next few weeks we will be working on a detailed review of the Pentax K20D performance. Looking around the web, there has been so little information available about the k20D that we felt our readers would appreciate some first impressions. As you have probably already figured out, we were also impressed enough in our early testing that we wanted to share what we've found so far with you.

Resolution and Image Quality
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  • Wesley Fink - Tuesday, March 11, 2008 - link

    There is hardly universal agreement with your 10 megapixel answer. This is from Brad Templeton in "How many pixels are there in a frame of 35mm film?" at http://pic.templetons.com/brad/photo/pixels.html">http://pic.templetons.com/brad/photo/pixels.html

    "This is a somewhat controversial question, and there are many possible answers. Film is an analog medium, so it doesn't have "pixels" per se, though film scanners have pixels and a specific resolution.

    Today the one thing most people agree on is that it's a more than any current consumer digital camera. The debate is about how much resolution the digitals will have to reach to start matching the film.

    The very short answer is that there are around 20 million "quality" pixels in a top-quality 35mm shot. That's a shot with a tripod, mirror-up, with a top-rate lens and the finest-grained film, in decent light. 12 million are more typical for "good" shots. There may be as few as 4 million "quality" pixels in a handheld shot with a point-and-shoot camera or camera with a poor lens. And of course if focus is poor, or light is poor, or the camera was not held steady, the number will drop down below the 1-2 million pixels of the modern consumer digicam. Of course, one can have a bad shot with a digital camera too, not using all its resolving ability. However, few pick their gear with the plan of shooting badly.

    The eye, however, is not as discerning when looking at a picture in the usual context as it can be when looking at things blown up. So many can also argue that a shot of around 9 million pixels would look as good to the eye as a 35mm shot, except when blown up very large and looked at quite closely."

  • Wesley Fink - Tuesday, March 11, 2008 - link

    www.clarkvision.com measured all formats and found 35mm Fujichrome Velvia required 10 megapixels to accurately portray color intensity but 16 megapixels to accurately portray color detail. Black & White Tech Pan required 16 megapixels to accurately convery the same information on a digital sensor.

    It is very interesting that Medium format (6x4.5mm) required a sensor resolution of 31 megapixels to 52 megapixels to convey the same information as Velvias on a medium format camera. Large format 8x10 view format required an amazing 600 to 960 megapixels to covey the same info.

    It appears there are many opinions as to the true digital "equivalent" to 35mm resolution. The Pentax figure of 14.6 megapixels seems like a pretty good value in the ranges I have seen for 35mm film. However the equivalent resolution required for Medium Format and 8x10 View should amply show we have a long way to potentially go in sensor resolution.
  • spazmedia - Tuesday, March 11, 2008 - link

    Thanks for the info. While the maximum resolution you quote from various websites is at around 16megapixels for film cameras (at iso50-100 it should be note) the sensor on the K20D as you well know is not 35mm. In any case for general purposes photography, you really don't need all that resolution (inc. landscapes). With film you also needed to deal with grain when enlarging, which is absent with all modern digital cameras. But camera makers need to sell cameras and increasing resolution is a sure fire way to do so.

    And you will never match medium/large formats in terms of resolution on an APS-c sensor as you are diffraction limited. Which makes increases in resolution even more useless.

    But the most important, an you pointed this out very well, is that the new Pentax K20d is a joy to use. now if only I can justify to my wife why i need another camera!!!
  • Wesley Fink - Tuesday, March 11, 2008 - link

    ISO is displayed in the Viewfinder when you select the Sensitivity (Sv) program. In this mode the ISO is underlined and you can adjust the ISO in half-steps (100, 140, 200, 280, 400, 560, 800, 1100, 1600, 2200, 3200, 4500, 6400) using the rear dial and see the changes in ISO in the viewfinder. As in other shift modes the ISO value blinks if an ISO you select is out of range for a correct exposure with the lens you are using.

  • Cideway - Tuesday, March 11, 2008 - link

    Hyper Program was first released in the Pentax Z1 in 1991. It consists of 2 dials and a green button, Front dial is Tv, rear dial is Av and the green button resets to the Program line. Turn either wheel at any time and you will change priority. The next element of HyP is the Program line its self, you have four options to choose from, Normal P, Hi P, Depth P and MTF P. Normal is as it says, while Hi is biased towards high shutter speeds, Depth is biased towards large DoF and MTF is biased towards the Lenses best aperture. (All Pentax Lens Designs are MTF tested and the data is encoded into the Lens, while FA* and DA*s are individually tested as are the FA and DA LTDs). I haven't used the Minolta system but nothing from Nikon or Canon quiet compares with HyP from Pentax.
  • dug777 - Tuesday, March 11, 2008 - link

    Aha!

    I understand the latter part of that explanation to be very different from what I am familiar with from Nikon(and pretty neat too).

    Other than that, it appears the shifting priority is pretty convenient, using either dial.

    Sensitivity Priority however, sounds exactly, 100% identical to what my Nikon does on Program Auto with a fixed ISO. You select an ISO value (check). You point the camera at on object. The camera picks what it considers to be the best aperture & shutter settings to maintain that ISO (check).

    You can even then roll the main command dial to roll through different combinations of shutter speed and aperture which give the same exposure (which is a less simple version of those four program modes you describe, I don't know what 'biases' it works through there).
  • dug777 - Tuesday, March 11, 2008 - link


    As far as I'm aware, most manufacturers offers variants of this. Shooting program auto, shutter priority, aperture priority, and full manual with my D80 I've a choice of locking the ISO, or allowing the camera to vary it.

    Program auto lets the camera do everything, and rotating the main command dial in this mode lets you choose between different aperture/shutter combinations that produce the same exposure. On shutter priority, the camera controls the aperture, and vice versa for aperture priority. Finally on full auto you control the shutter & aperture (using the front & main command dials).
  • Wesley Fink - Tuesday, March 11, 2008 - link

    In Pentax Program mode the front dial adjusts shutter speed and the rear dial adjusts aperture. When you click either dial the corresonding value you are adjusting is underlined in the viewfinder. Hyperprogram shifts the corresonding value to keep the same exposure, and it blinks if you select a value outside the exposure range. the shifted value survives an auto LED shutoff and remains underlined so you can instantly see what you shifted. You can turn off the shift and return to regular program mode by hitting the green dot button next to the shutter release and front dial.

    Most other companies now have some variation of this feature but the Pentax implementation is still the most logical, most complete, and easiest to use in my opinion.
  • Johnmcl7 - Tuesday, March 11, 2008 - link

    I have to admit having read through the posts I don't see what is so much simpler about other manufacturers - on the Olympus E-3 when in program mode you turn the front dial and it switches to shutter priority (the display changes to Ps to show you've changed it). Alternatively if you want aperture priority you turn the rear dial, it won't let you underexpose (without using EV compensation) but that seems reasonable.

    However I think Panasonic have by far the simplest implementation on their L1 - it has a dedicated shutter dial and aperture dial (on Panasonic lenses), by default the aperture and shutter dials sit at 'A' which is full automatic control, the camera chooses both. If you want to choose shutter priority you just turn the shutter dial and the camera will work out an aperture for you. If you want aperture priority you turn the dial and choose an aperture, the camera will work out shutter speed if that's still on A. If you want full manual control just choose both an aperture and shutter value. Any time you want to switch back to automatic on either aspect you just turn the dial back, aside from being simple there's the obvious benefit that even with the camera powered down you can see what aperture/shutter is set to and also change it without switching the camera on.

    John
  • Heidfirst - Tuesday, March 11, 2008 - link

    I'll give you the Programme Sensitivity being unique but the rest doesn't seem too different to Minoltas going way back - my 1993 Dynax 700Si has it.

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