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05-29-2011, 02:23 PM   #1
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k-x noise

I'm still figuring things out. My fav shots to do are outside, natural light action shots. Recently, I've been doing more setting changes while still working in green auto. Apparently, I've made the wrong adjustment cause I'm getting noise/static in my pics. Not much but I can't figure out what to put back. The only settings I've messed with is ISOs, Av, my jpegs are at 12m and I do MF usually.

For example:





Shot at 1/6000s
f/22.0
iso 6400
37.5mm
untouched image

05-29-2011, 03:11 PM   #2
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Shoot with lower ISO settings. 6400 is very high for outdoor daylight situations. Try to keep this as low as you can because it directly affects noise level, however don't go so low that it will affect your shutter speed.

Your aperture is very small too (f22). did you need that? You could lower this number too. Bigger apertures (lower numbers) also means you can get by with lower ISO.

Shutter speed is very high too. Could have been lower as well.

Ps. Apertures past f16 or so can affect image quality as well. Depends on the quality of the lens.

Last edited by Zafar Iqbal; 05-29-2011 at 03:17 PM. Reason: typo
05-29-2011, 03:15 PM   #3
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Put simply, its your ISO setting thats giving you noise. Higher ISO = more noise
was there any particular reason you wanted to shoot at f/22 and 1/6000s? choosing a wider aperture and slower shutter speed would most definitely have allowed you to shoot at a lower ISO
05-29-2011, 03:18 PM   #4
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I think you've changed the ISO of your camera to 6400 and as a result your getting crazy settings (f22 1/6000). Push the ISo button (right of OK), push the up button to select auto ISO (up button), push "OK".

Should be all good.

Then you need to pick up a copy of this from amazon so you can understand the basics of exposure, it will help your photography no end

05-29-2011, 03:18 PM   #5
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QuoteOriginally posted by WDWmom Quote
Shot at 1/6000s
f/22.0
iso 6400
37.5mm
untouched image
ISO6400 is a very very high sensitivity and would be quite noisy -
your shot is actually pretty good for ISO6400 -
it would have been considered astoundingly good just a few years ago.

Your shutter speed is 1/6000 sec - that is really fast - 6x faster than even electronic flash 1/1000 sec.

Your aperture is f/22 most people would recommend not going smaller than about f/16 as the image probably will degrade due to diffraction.

So....
for the same exposure you could have shot at
ISO200 - f/8 and 1/1500s
or even
ISO100 - f/8 and 1/800s

Both of these setting would have given you virtually no noise/grain -
you would also be shooting with the lens's optimum aperture with a shutter speed that is very unlikely to be affected by camera shake.

Last edited by UnknownVT; 05-29-2011 at 03:25 PM.
05-29-2011, 03:20 PM   #6
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You do not mention which camera however, your shot was taken at 1/6000 which I believe is as fast as the k-x or k-r can go. There is no reason to be shooting that fast. Also your aperture is set at f/22. Again no reason at all to be using a setting that extreme for that type of shot. In order to have a good exposure at those settings the ISO has then to be set very high because you are not letting much light in. Noise can be caused by several things but high ISO is a leading cause. Normally I would only use ISO 6400 in extremely dark places where it was the only way to get the shot.

ISO, aperture and shutter speed are the triad of exposure controls. There are many combinations of those settings that will result in a correct technical exposure but only the photographer can set the combination that results in the right combination. The important thing to remember is that they all affect the same thing! Move one in one direction and you must move one or both of the others to compensate. Nothing but frustration for the photographer that does not understand this.

In short for an outdoor shot in sunny weather I would set the ISO at 100 or 200, then set the aperture to where I wanted it for the shot, perhaps f/5.6 or f.8 for the shot in your example and then set the shutter speed to get a good exposure.

Try setting the camera to Av mode, set the ISO to 200 (for outdoors) (400 to 800 for indoors) set the aperture to f/8 as a good middle starting place and then the camera will adjust the shutter speed to obtain a correct exposure.

If you really want to understand this and take good photos with a dslr may I suggest Bryan Peterson's book "Understanding Exposure" it is available at most bookstores and on line and your library might have one as well. I think it will be the best investment in time you could make to get started right.
05-29-2011, 03:33 PM   #7
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QuoteOriginally posted by jatrax Quote
You do not mention which camera
The title says K-x
Well written suggestions, Jatrax.
@OP, you can also use preset conditions on the mode dial settings (depends on the lenses, A, F etc), they are also a good place to start.
05-29-2011, 03:53 PM   #8
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QuoteOriginally posted by ultraviolet Quote
The title says K-x
Well duh... Somehow I knew we were talking about a k-x but by the time I finished the post I forgot where I saw that, even went back and read the OP.

05-29-2011, 04:09 PM   #9
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If you read the OP it's no mystery what's going on here. The OP'er didn't choose f/22 and didn't choose 1/6000, what happened is that the OP'er fiddled with the ISO setting and put the camera onto fixed ISO of ISO6400. This forced the camera to make the shutter and aperture settings to cope with the ISO setting.

The fix is easy, get the camera off ISO6400 and back to auto ISO.... then they should read an intro to photography book (eg "Understanding Exposure").
05-29-2011, 04:30 PM   #10
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thanks, everyone. That's what it was. I had to ISO manually upped from taking dark shots in my living room. The others were automatically changed because of that. I'm actually not sure how to manually adjust the shutterspeeds other than the presets on the dial (sport, night, landscape, etc).

When I first bought my k-x, the screen went black after only a month. I didn't get it fixed until the last month of my warranty(forgot I had one) so I just got it sent back to me maybe a month ago. Now I have to learn everything.

Thanks for the book recommendation

edit~nevermind on the shutterspeed adjustment *blush*

Last edited by WDWmom; 05-29-2011 at 04:36 PM.
05-29-2011, 04:38 PM   #11
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QuoteOriginally posted by WDWmom Quote
thanks, everyone. That's what it was. I had to ISO manually upped from taking dark shots in my living room. The others were automatically changed because of that. I'm actually not sure how to manually adjust the shutterspeeds other than the presets on the dial (sport, night, landscape, etc).
Shutter speeds can be set directly in Tv or M mode. I wouldn't worry about that for now, I'd try and get off green auto and into "Av" mode (aperture priority). Even pros tend to use this mode most of the time.
05-29-2011, 04:40 PM   #12
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QuoteOriginally posted by twitch Quote
Shutter speeds can be set directly in Tv or M mode. I wouldn't worry about that for now, I'd try and get off green auto and into "Av" mode (aperture priority). Even pros tend to use this mode most of the time.

Thanks! I'll do that.
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