June 17, 2009

K-7 final firmware and tungsten high iso noise

I have just received the final firmware v1.00 and wanted to make available some samples shot at ISO 400-6400 in tungsten light (2900/2950 K, using Auto WB). Shot with the kit lens and AF focussing onto the SD card in the center.

This is a preliminary article and my evaluation of noise is pending. Also, the subject is not ideal (colors missing, no gray card). I was in a hurry. The ball's surface has a subtle texture looking like noise but not being noise (in iso 400)! So, this may be used to compare denoising artifacts.

The camera was set to "natural" (default is "bright") and default settings otherwise (i.e., sharpness -1, NR medium, NR start iso800).

The images are here (out of camera or Lightroom standard settings):

K-7 Tungsten high iso noise

And the DNG raw files are here:

Preliminary test, firmware is final but the sensor in my preproduction camera is said by Pentax to be different from the final one!

This is very warm tungsten (below 3000 Kelvin). In daylight, the noise would be much less. Also, ISO6400 is not a fully advertized feature.


  1. Nice job, Falk! Btw, did you apply any Noise Reduction for any of the five higher/high ISO shots?

  2. Thanks for the test. And special thanks for using the "natural" color mode. Still, the colors look really different from the camera and from Lightroom, can you comment which is closer to reality?

  3. A great help for judgment would be a direct comparison with the K20.
    Make sure to use the same settings as far as possible.

  4. A very nice series of images; although I'm sure results would have been better, had you used EV +0.7

  5. Thanks Anonymous for your comment: it is interesting to see that you have all the answers before the tests are performed. Great for you.

    Since there is no need for reviews, it is useless for you to pay visits to that kind of blogs: so you might as well just do us a favor and not comment, or even better not come and visit at all. Disconnect from the internet, and live a long narrow-minded life, away from us.

    Bye ;)

  6. I think anonymous has a point. Pity some people can't take constructive criticism.

  7. What he says is bullshit. The shutter time and aperture at ISO3200 simulate dimmer light. Therefore this test is completely legitimate. The only problem I see, is that the shot is gravely underxposed and underexposed images, especially in reddish or orangish parts, ALWAYS show noise. Even with Full frame, which by the way gives you an advantage of 1 ISO setting at best, bye the way.

  8. Very nice. I note that when opening the DNG files in ACR, they can be bumped up by about one whole stop. Thus I see the ISO 3200 noise as closer to ISO 6400 noise in a well-exposed photo.

  9. I don´t get it. You say the sensor in your camera isn´t the one that will be in the K-7? Then what´s the purpose with your test?

  10. I removed a troll posting (then commented by Paul).

  11. @RiceHigh: default NR in LR (25% chroma noise), default NR for JPGs out of camera (as decsribed above).

    @Pawel: The LR colors are a closer match to what my eyes believe to see;)

    Yes, the images would look better if not underexposed by about 0.7EV. But noise is a problem in shadow areas mostly and there is no big deal to have little noise on a bright surface. I WANTED to know what noise looks like in a difficult situation.

  12. About the sensor in my camera and production units:

    I've been told that there may be minor (~5%)differences between my camera's sensor and the production run. And that firmware be optimized for the latter.

    So, I think my results are good tests of what to expect from the production cameras. Final results may be just a little better. Pentax asked us to refrain from noise tests before the final firmware is out and now just asks us to put this little disclaimer with our results.

  13. Very nice Falk, i wanted to ask if you were to choose between the canon 50D or the K-7 which is better? as i am deciding on these 2, also is the high ISO noise better than the K20D?
    as far as my photography i shoot landscapes, weddings portraits, and sports thank you

  14. Sorry i just saw the Noise test for the k-7 and K20D,, ok how about the 50D noise compared to the K-7? thanks.

  15. Very good info. Hopefully I stand a chance to do some K-7 hands on and from there I'm able to understand more about it's features :)


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