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01-10-2010, 09:18 PM   #1
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Is This Noise to Be Expected?

Below are a couple of pics from my K20D with the kit lens. At ISO 200, and even 100 there is definite visible noise. They were shot RAW with in-camera NR turned on, cropped at 100% and saved as JPEG (noise in RAW images was very close to the JPEG). Is this amount of noise to be expected (the portion at the bottom of the helmet, below the ears)?

f9.5
1/8 sec
24mm
ISO 200




f9.5
1/4 sec
24mm
ISO 100


I'm a bit disheartened . If this is the kind of noise I'm getting at 1/8 and 1/4 second, I don't hold much hope for long-exposure work.

z

01-10-2010, 11:01 PM   #2
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Ok, I feel like an idiot...

What noise where?

If I crank my screen brightness, I can see some areas that are mottled where there are areas of pure black beside areas of very dark grey. Is this what you are talking about?
01-10-2010, 11:02 PM   #3
Damn Brit
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It's hard to see what we're looking at with such small images but I don't think this is the same as noise you would expect with higher ISO's and low light levels.

Try playing around with your colour and saturation settings in camera to see if that makes a difference.
01-10-2010, 11:20 PM   #4
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QuoteOriginally posted by KungPOW Quote
Ok, I feel like an idiot...

What noise where?

If I crank my screen brightness, I can see some areas that are mottled where there are areas of pure black beside areas of very dark grey. Is this what you are talking about?
Well, it's quite possible *I'm* the idiot here . Yes, the mottled gray area (I updated the photo and drew a red box around it). I wasn't expecting to see this at low ISO in a light box.


QuoteOriginally posted by Damn Brit Quote
It's hard to see what we're looking at with such small images but I don't think this is the same as noise you would expect with higher ISO's and low light levels.
It does seem to be slightly better at ISO 100 than 200. Maybe I'll zoom in and get a larger pic, if that would help any.


QuoteOriginally posted by Damn Brit Quote
Try playing around with your colour and saturation settings in camera to see if that makes a difference.
Would shooting RAW ignore these settings?

Thanks for the replies.

01-11-2010, 12:09 AM   #5
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QuoteOriginally posted by zombieCat Quote

Would shooting RAW ignore these settings?
I don't shoot RAW so I can't answer that one I'm afraid.

Did you check the model closely to make sure it isn't mottled?

Seriously though, I'm pretty sure this isn't the same as low light, high ISO noise.
01-11-2010, 08:24 AM   #6
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I double-checked the model--it's quite smooth. Now that I view this on my work monitor rather than my laptop, I'm seeing why everyone must think I'm crazy. On this one, even when I crank brightness/contrast to extreme levels, I can't really see what I was seeing on my laptop. Using the laptop, there is definite mottling in the area I highlighted. Sounds like a good excuse to get a Mac (any excuse will do, right?)
01-11-2010, 08:56 AM   #7
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QuoteOriginally posted by zombieCat Quote
I double-checked the model--it's quite smooth. Now that I view this on my work monitor rather than my laptop, I'm seeing why everyone must think I'm crazy. On this one, even when I crank brightness/contrast to extreme levels, I can't really see what I was seeing on my laptop. Using the laptop, there is definite mottling in the area I highlighted. Sounds like a good excuse to get a Mac (any excuse will do, right?)
Forget laptop monitors. Even the Mac ones are not really good, though perhaps better than cheapo Noname ones. As you just noticed a "real" monitor is the only viable option.

Ben
01-11-2010, 10:41 AM   #8
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QuoteOriginally posted by zombieCat Quote
Well, it's quite possible *I'm* the idiot here . Yes, the mottled gray area (I updated the photo and drew a red box around it). I wasn't expecting to see this at low ISO in a light box.
Those areas are pretty close to black. It seems to me that ff there's going to be noise at low ISO, as the difference between "1" and "2" is a lot bigger than the difference between "253" and "254". Well, whether or not that simplistic explanation really applies, the phenomenon is really. Anyhow, if that's a 100% crop, and no one else can see what you're talking about, and you can only see it on one monitor, chance are, that monitor is just turned up too bright and is exposing differences between "1" and "2" that shouldn't really be so visible. Most monitors are calibrated far too bright - good for reading text, bad for evaluating pictures. Definition consider calibration between simply chucking the monitor.

But in any case, when seeing tiny amounts of noise in deep shadows like this, the simple fix is to push those values even darker in PP using levels and/or curves. You could also try using NR, but tht seems overkill - it would probably kill some detail too.

QuoteQuote:
Would shooting RAW ignore these settings?
Well, the setting wouldn't affect the raw data itself - nor does your turning NR on in camera, for that matter. But many raw processing programs do look at the EXIF to see what settings you used and then try to reproduce them in their own default conversion. In an case, whether or not the settings are honored by your raw software automatically, you could certainly just move the sliders yourself (or create a preset that has a combination of settings you find you like).

01-11-2010, 12:27 PM   #9
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QuoteOriginally posted by Marc Sabatella Quote
Those areas are pretty close to black. It seems to me that ff there's going to be noise at low ISO, as the difference between "1" and "2" is a lot bigger than the difference between "253" and "254". Well, whether or not that simplistic explanation really applies, the phenomenon is really. Anyhow, if that's a 100% crop, and no one else can see what you're talking about, and you can only see it on one monitor, chance are, that monitor is just turned up too bright and is exposing differences between "1" and "2" that shouldn't really be so visible. Most monitors are calibrated far too bright - good for reading text, bad for evaluating pictures. Definition consider calibration between simply chucking the monitor.
Makes sense. I think I'll try to calibrate the monitor (as soon as I can make buying a calibration system a priority )

QuoteOriginally posted by Marc Sabatella Quote
But in any case, when seeing tiny amounts of noise in deep shadows like this, the simple fix is to push those values even darker in PP using levels and/or curves. You could also try using NR, but tht seems overkill - it would probably kill some detail too.
I'll give this a try on some images where slight noise shows on a good monitor.

Thanks for the info Marc (and everyone else).
01-11-2010, 12:35 PM   #10
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You maybe seeing posturisation and clipping by the laptop monitor, it looks just like noise at times.
01-11-2010, 02:35 PM   #11
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QuoteOriginally posted by zombieCat Quote
Makes sense. I think I'll try to calibrate the monitor (as soon as I can make buying a calibration system a priority )

You don't need to spend more than about $70 on a calibrator. The Spyder2Express is a popular one.
01-11-2010, 07:29 PM   #12
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OK, now that I've run through my laptop's basic built-in monitor calibration, the images look more like I would expect. The gamma and brightness/contrast were way out of whack. Much ado about nothing, it appears. Thanks for the input everyone. And I'll definitely check out the Spyder2Express--thanks for the info Damn Brit.
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