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  1. #1
    Kentucky Wildlife
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    Higher ISOs with K20D

    For over 30 years, I've shot everything with as low an ISO as possible, because image quality is important to me, but I experimented today with some shots comparing the same scene shot with ISO 100 and ISO 800 and couldn't detect any noise at the higher ISO.
    This really impressed me, and I've adjusted my auto range to span 100-800, which gives me much more latitude during low light conditions.
    Now I'm wondering how far I can go, and if anyone knows at what level of ISO the K20D starts getting noisy?

  2. #2
    Junior Member
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    Re: Higher ISOs with K20D

    good question
    I saw some taken over 1000 ISO + (I could not get close enough to see) processed with noise ninja at a local camera store
    printed at 11 by 14 look good to me.
    would have loved to chat with the owner of the k20 but no luckhttp://forums.photographyreview.com/images/smilies/cool.gif

  3. #3
    Moderator Didache's Avatar
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    Re: Higher ISOs with K20D

    I use the K10D and know that I can easily get away with 800 ISO with little or no discernable loss of quality (except maybe for some very dark areas where a little noise creeps in). I found that 1600 does start to show a little, but a friend of mine with the K20D thinks the imaging engine on board that camera allows a little extra push. I think it's a good general principle though to keep the ISO as low as possible.

    Cheers
    Mike
    Mike Dales ARPS
    My website: www.mikedalesphotography.co.uk

  4. #4
    Kentucky Wildlife
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    Re: Higher ISOs with K20D

    That's still my philosophy too, Mike, but the difference in what I can do with shutter speed and/or apature is considerable between ISO 100 and 800. I mean, I feel like it's Christmas and I've just been gifted a pair of super-duper Batman spy goggles.
    That, and the results of some tests I did with IS on and IS off (posted in the Wildlife and Nature thread) has really turned me back on about this K20D.
    To tell you the truth, after shooting this camera for six months, I was beginning to wonder if I had made a mistake not sticking with Nikon or not switching to Canon or Sony instead. But I'm very pleased with this camera and especially with the DA* 200mm. I've sold five covers since getting it.
    I'm still on a digital learning curve, because I held out with my Nikon film camera and a good scanner until I simply had no other choice, but I've leanred a great deal since joining this forum.
    I'm going to do some comparisons of 100 and 1600 today.

  5. #5
    Moderator Didache's Avatar
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    Re: Higher ISOs with K20D

    Ron: Please let us know your results - just on Monday I was shooting some urban art in a dimly lit underpass - I got away with 800 ISO, but it would have been easier at 1600. I'd be very interested in what you discover.

    Cheers
    Mike
    Mike Dales ARPS
    My website: www.mikedalesphotography.co.uk

  6. #6
    Kentucky Wildlife
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    Re: Higher ISOs with K20D

    I just conducted some more tests on ISO and IS factors. I'll post the IS factors in the Wildlife and Nature thread and the ISO factors here, because the IS factors deal in a general way with long focal lengths, while the ISO factors are Pentax K20D specific:
    The general appearance of images between 1600 and 100 ISO is that 1600 is sharper and brigter, while the 100 is darker and richer under the same conditions.
    I attribute this to the fact that at 1600 ISO I got 1/1600 sec at F/9.0, while at 100 ISO I got 1/400 sec at F4.5.
    A lot of what I'm seeing is because of how the in-camera metering system is behaving under different settings, and these can be controlled by underexposing by -1/3 or over exposing by +1/3 as needed, or by auto-bracketing shots and then picking the one with the perfect exposure/saturaton/hue. (Exposure, of course, can also be altered in PP software to get the same thing, but my attitude is to get the best possible shot from the camera and do a little in PP as possible to maintain the integrity of the image, especially with JPEGs.)
    In the final analysis, the saturation and hue are the same regardless the settings, but the degree of that saturation/hue varies according to the f-stop/shutter speed relationship--not the ISO. As a general rule, exposures toward the darker side are going to have more saturation (and more dramatic hues), while those on the brigher side have less. (Am I making this clear?)
    Now for the biggy: noise.
    While I did detect a slight a increase in noise between 100 ISO and 1600 ISO, I believe that was offset by greatly increased general image sharpness (because of the much higher shutter speed and better DOF) at 1600 ISO. Again, the noise difference wasn't noticable until I magnified the image from the original size in the camera. This was the same for both the RAW and low-compression JPEGs of the same exact images.
    Though I haven't done this with test shots, I'm fairly certain that you won't be able to tell the difference between the noise of the same shots printed at 8x10, and you might even have a slightly sharper image from the 1600 version.
    For my purposes of reproductin in magazines, I'm confident that shots taken at 1600 will be fine for inside use, up to 5x7, but will be a little noisy for cover reproductions, so unless I have to take a picture of a black bear in a cave, I'll avoid it. (Keep in mind that the speed of the lens will affect all of this as well.)
    For me, the ISO breaking point sits at 800, so I'll leave my camera set on the 100 to 800 range for Auto Exposure, but in a pinch, when I cant use flash (such as with longer focal lengths) I'll push the ISO to 1600.
    For general photography that doesn't demand poster prints or reproduction in magazines, I believe my K20D would give tremendous range image quality with the Auto Exposure set from 100 to 1600.
    This camera is it's own "Noise Ninja." When I was debating between Nikon, Canon, Pentax and Sony for my digital plunge, I noticed Pentax bragging about the K20D's noise-reduction capabilities, but I always consider such hype with a grain of salt and didn't pay much attention to it, anyway, because for decades I had been convinced that the lower the ISO the better.
    I still feel that way, but this old dog is now taking a much more liberal attitude toward pushing ISO, based upon these experiments.

  7. #7
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    Re: Higher ISOs with K20D

    This is a interesting thread. I have the K10d and keep my ISO at 100-800 and depending on the light 100-400. I have to agree that ISO is a whole different animal in digital vs film

    My son just bought a K20d and he even spends more time than I do researching before purchasing some thing.
    One interesting thing he found out was a number of reviewers did not turn on the noise reduction before doing the review. :idea:
    K10d pentax 50-200 f4-5.6 sigma 100-300 f4 sigma 18-50mm f2.8 ex dc macro Kenko AF 1.5 DG

  8. #8
    Junior Member
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    Re: Higher ISOs with K20D

    Very interesting. I shoot with a K10D and I pretty much keep mine between 100-400. I have even seen some noise at 400 in dark areas but it depends on overall exposure obviously.

    Thanks for the reviews and information. The K20D is in my future.
    ~I'm really new at this and eager to learn. ~

  9. #9
    Kentucky Wildlife
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    Re: Higher ISOs with K20D

    One of the selling points of the K20D is less noise at higher ISOs.
    I saw one thread that claimed that the K10D, while having more noise at higher ISO, had less noise than the K20D at lower ISOs. I don't have both bodies with which to compare, but I doubt it. The lower the ISO the less noise is an issue.

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