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Pentax K20D Digital SLR - Test shots - ISO performance

By Cliff Smith



  • Recommended by TR
Pentax K20D Digital SLR


Our Score:


A range of test shots are shown over the next few pages. Here, the full size images at the minimum and maximum ISO settings have been reduced for bandwidth purposes to let you see the full image, and a series of crops taken from original full resolution images at a range of ISO settings have been included in order for you to gain an appreciation of the overall quality.


This is the full frame at 100 ISO.


Not surprisingly the image is totally noise-free at 100 ISO.


No significant difference at 200 ISO.


Still no problems at 400 ISO.


There is a little noise visible at 800 ISO, but not enough to worry about.


Slightly more noise at 1600 ISO, but you could still print this.


Significant noise at 3200 ISO, but the colours are still strong and bright.


This is the full frame at 3200 ISO.



January 14, 2009, 3:23 am

Still no comments after 9 months? OK I'll be first...

Cliff's is one of the few really fair reviews of this camera. Unusually he has good things to say about it's AF system. I agree with his comments - it is accurate and usually pretty fast. Admittedly it slows down quite a bit in low light.

Other reviews make a big deal about focusing being "noisy" - an odd complaint - do the same people complain that their kettles make whistle and ping noises? Unless you are a ninja, you are likely to be making just as much noise as your camera anyway...

Yes, exposure metering could be improved. I appreciate the argument that it deliberately underexposes to retain highlight detail, but I have exposure compensation to do that if I want. The problem is more one of consistency. Compared with a D300, the Nikon will get exposure exactly right 99% of the time, the Pentax "only" 90%. Then again, it's never very far off, and the great dynamic range means it's not a great problem (especially if you shoot RAW).

Cliff is also one of the few reviewers to not criticise it's high ISO noise performance. Everyone else seems to ignore the fact that noise reduction is switched off by default, so of course it suffered in comparison with other cameras. Personally I set NR to it's lowest setting, as I'd rather keep more detail. Software continues to get better at removing noise - much less likely that it can add detail which was smeared away.

Above all Cliff is right to give it 10/10 for value. Quite how other reviewers failed to see this is beyond me. One magazine roundup recently gave the Nikon D300 a better value-for-money rating - madness. The D300 is a fantastic camera and I would love to own one, but the fact is that the Pentax does most of what the D300 does, does it very nearly as well, but does this (with cashback) for about HALF the price! Considering that the range of available lenses is also improving, you'd be mad not to consider the K20d if you're looking for a proper enthusiast's camera.


January 15, 2009, 6:33 am

I should correct my previous post... my comments regarding exposure metering refer to multi-segment metering mode. I have found no problems with the accuracy or consistency of center-weighted or spot metering.


February 23, 2010, 8:01 am

Good review. This is very informatove.

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