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12-18-2011, 12:03 AM   #1
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Noise: Am I doing something wrong?

Before buying the K-5 a couple of weeks ago, I was intrigued by samples of high-ISO shots straight out of camera that looked decent in shadow areas even up to ISO 12,800. So after a couple of sessions at the local hockey arena, I'm getting noise that I don't think I should be getting even at ISO 6,400. Here's a sample from an ISO 8,000 shot, and keep in mind that I've shut off any noise reduction. This is a from a screenshot of a 100% zoom of one of my RAW files in Lightroom.

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Now my first question is, am I being unrealistic, i.e. is this not noisy for the K-5 at ISO 8,000? If this is an unusual amount of noise for the K-5 at this ISO, what might I be doing wrong?


Last edited by enoxatnep; 12-18-2011 at 12:13 AM.
12-18-2011, 12:15 AM   #2
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For a 100% crop, of a shadow area, of an ISO 8000 image (!!!) the result is normal.
It should also clean up very well with a bit of judicious NR. There's still decent detail in there.

What does the whole image look like BTW?
12-18-2011, 12:19 AM   #3
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this is pretty normal for what you've got. you'd probably have a bit less noise if you exposed it properly.
12-18-2011, 12:40 AM   #4
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This is pretty much what I would expect at ISO 8000 and 100%. (However, downsizing a frame to suit screen display with some (luminance as well as color) noise reduction (and not overdoing sharpening) can still yield decentish results. Also, a BW conversion is (sometimes) an option, with that a bit of grain might even look good ).

12-18-2011, 01:31 AM   #5
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QuoteOriginally posted by enoxatnep Quote
...and keep in mind that I've shut off any noise reduction.

...am I being unrealistic, i.e. is this not noisy for the K-5 at ISO 8,000? If this is an unusual amount of noise for the K-5 at this ISO, what might I be doing wrong?
I'm not quite sure what you are asking. Is it normal for a camera, ANY camera, to display noisy images at ISO8000 whith its NR-processing shut-off? Yes, entirely normal with any camera from any brand! So now what? The advertising didn't claim the K-5 was noisefree when you shut down its processing, IMHO you make a choice: NR in-camera or NR on the PC.

Your best bet is to shoot RAW+ with NR switched on. This way you have the camera-JPG with its noise reduced by the camera processing, and the PEF file to deal with on the PC with noiseware after raw conversion(I often do that and then pick the best)
12-18-2011, 04:07 AM   #6
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Hi

If it cleans up like this I think you should be quite happy, this at ISO 8000 a few years back would have been quite unthinkable.

Greetings

Last edited by Schraubstock; 06-05-2012 at 06:41 AM.
12-18-2011, 08:30 AM   #7
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I was just playing around, I know you didn't ask anyone to. I also have a tendency to be a bit heavy handed (and needing practice) with the NR, but here's what I got, side by side.

I think I sacrificed a bit too much detail.

Seriously tho, you're not going to be using this kind of shot at 1:1 anyway. You'll be able to do much better by denoising and adjusting the original, and resizing it down for web or screen.
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12-18-2011, 09:15 AM   #8
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Thanks everyone for your input. I was just wanting to know what was reasonable to expect at such an ISO; now I'm at peace that it's me instead of my new K-5! When I saw shots straight OOC like this one at ISO 12,800 that are remarkable compared to my ISO 8,000 shots, I began to wonder about what I might be doing wrong. I think I might know now.

Admittedly, the crop I put in the original post had been underexposed in that portion of the photo and so I first brightened it in Lightroom, and that of course enhanced the noise that was already there. So I think that ISO 12,800 shot I've linked to was obviously exposed properly and thus had less noise in the first place. I also realized that when shooting white-background scenes in an arena, I need to do the +0.7 exposure compensation that I always (try to remember to) do when I'm outdoors shooting in snow.

12-18-2011, 11:37 AM - 1 Like   #9
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QuoteOriginally posted by adpo Quote
this is pretty normal for what you've got. you'd probably have a bit less noise if you exposed it properly.
Could you explain? I had exactly the same question when I saw the linked chorus photo at high ISO. I'm getting more noise than that at 800 iso in some of my shots.

On a shot like this you have whites from the ice and boards which would tend to under expose the players. I had a similar shot the other day with a dark bird surrounded by snow, and I had blown low lights, or noise with no detail in the dark sections. That I understand, it is a matter of choosing sometimes which details you wouldn't mind blown. Some blown highlights in the snow would have given me more detail on the bird. There are limits to the dynamic range of the sensor.

But at a given iso level, why would some shots have more noise than others? What factors other than iso level would give you more noise? Is the difference due to the lowered dynamic range of the sensor at high sensitivity levels, where being off on the exposure is evidenced by noise?
12-18-2011, 02:00 PM   #10
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QuoteOriginally posted by derekkite Quote
Could you explain? I had exactly the same question when I saw the linked chorus photo at high ISO. I'm getting more noise than that at 800 iso in some of my shots.

On a shot like this you have whites from the ice and boards which would tend to under expose the players. I had a similar shot the other day with a dark bird surrounded by snow, and I had blown low lights, or noise with no detail in the dark sections. That I understand, it is a matter of choosing sometimes which details you wouldn't mind blown. Some blown highlights in the snow would have given me more detail on the bird. There are limits to the dynamic range of the sensor.

But at a given iso level, why would some shots have more noise than others? What factors other than iso level would give you more noise? Is the difference due to the lowered dynamic range of the sensor at high sensitivity levels, where being off on the exposure is evidenced by noise?
Any time that you have to increase the exposure in post, you will be amplifying the noise that is latent in the shot. Underexposing also tends to emphasize noise even more when you fix it.
12-18-2011, 02:06 PM   #11
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well...if u r outdoor at day time..even u use ISO 25600..the noise would be less than a ISO 3200 indoor at dark area...
this is how the ISO works...
12-19-2011, 01:58 AM   #12
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You are comparing two completely different things. The ISO 12800 shots you link to have been (massively) scaled down. I took the liberty of scaling your crop down to match. Not so noisy now, eh?
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12-20-2011, 01:10 PM   #13
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Good point, drougge. I also wonder how much noise would get "disguised" if one made a 4x6 or 5x7 print of a photo like this? By the way, you don't need to use the word "eh" just because I'm a Canadian, unless it's a word you Swedish folk also happen to use when speaking English!
12-20-2011, 11:29 PM   #14
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QuoteOriginally posted by enoxatnep Quote
Thanks everyone for your input. I was just wanting to know what was reasonable to expect at such an ISO; now I'm at peace that it's me instead of my new K-5! When I saw shots straight OOC like this one at ISO 12,800 that are remarkable compared to my ISO 8,000 shots, I began to wonder about what I might be doing wrong. I think I might know now.

Admittedly, the crop I put in the original post had been underexposed in that portion of the photo and so I first brightened it in Lightroom, and that of course enhanced the noise that was already there. So I think that ISO 12,800 shot I've linked to was obviously exposed properly and thus had less noise in the first place. I also realized that when shooting white-background scenes in an arena, I need to do the +0.7 exposure compensation that I always (try to remember to) do when I'm outdoors shooting in snow.
I've been shooting my new K5 at ISO 12800 quite a bit since I've mostly been out at night and indoors and no choice. Increasing the exposure in Lightroom or any other editing program is asking for trouble at high ISO. I think you found that out. I think 100% crops are kind of pushing the limit also. This is a 12800 shot I got this past weekend. Very little NR.
[IMG][/IMG]
This shot is better than shots I got last year at the same party in the same place with my K10D and Metz flash at ISO 400. I regularly have to use NR on ISO 400 shots on the K10D. Of course, this shot isn't cropped but I'm very satisfied at the results I've been getting. I haven't mounted a flash on the K5 yet.
12-20-2011, 11:38 PM   #15
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QuoteOriginally posted by enoxatnep Quote
Good point, drougge. I also wonder how much noise would get "disguised" if one made a 4x6 or 5x7 print of a photo like this? By the way, you don't need to use the word "eh" just because I'm a Canadian, unless it's a word you Swedish folk also happen to use when speaking English!
Everything always looks worse on the computer. Well, except when it looks better, I suppose. (How's that for useful?)

I don't know about us in general, but I use it sometimes. Didn't check where you were from or anything. (And I have been to Canada, if only briefly.) As a non-native speaker I tend to mix up regional usage a bit.
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