Noise at my photo

[scottkiller]

Hi,

I brought my D3000 iwth 18 -55 kit lense at last Dec 09. And recently found that when i took my photo and zoom at 100% on my pc. i found that the pic is not really sharp and hv a lot of noise. But sometimes when i shot under sunlight..(say 12 noon) it dun hv the noise (only sometimes) i try to use ISO below 400 most of the time to avoid this and i on my noise reduction function as well...

Wondering if it was my setup of the camera or is because of the camera itself.. other reason...

Would like to hear from you guys to point out how i should be overcome this kind of problem. Thx



Camera: Nikon D3000
Exposure: 0.006 sec (1/160)
Aperture: f/22.0
Focal Length: 18 mm
Focal Length: 18.3 mm
ISO Speed: 100
Exposure Bias: 0 EV
Flash: No Flash


P/S : i try to upload my photo in 100% size but dunno why flickr automatic reduce to 1024 X 658..)

[dcclark]

I don't see any noise to speak of in that photo. If you can't see it at this size, I can't see how it matters!

Also, I'm wondering if you're really seeing "noise", or whether perhaps it's just the typical lack of sharpness which you notice when pixel-peeking. Digital photos are imperfect, but only if you're trying to smell them instead of LOOK at them. :P

[Almond.Butterscotch]

Originally Posted by dcclark

but only if you're trying to smell them instead of LOOK at them

haha- that may have made my day.

[OsmosisStudios]

You're at f/22, so it's likely softness due to diffraction. At 100iso, you shouldnt be seeing any noise

At this size I can also see some rather heavy green fringing where the hills meet the sky

[dcclark]

Good point OsmosisStudios. That fringing may be what the OP is looking at.

The green fringing will be a result of the lens (it's called "chromatic abberation" and is the result of the optics being imperfect). All but the best lenses have SOME degree of abberation, and bright light with high contrast edges tend to show it more.

It could be diffraction, but if you're looking at 100%, you're just as likely to be seeing the results of imperfect focus, chromatic abberation, diffraction, atmospheric distortion, and who knows what else, all wrapped up into a handful of pixels.

[scottkiller]

Originally Posted by dcclark

Good point OsmosisStudios. That fringing may be what the OP is looking at.

The green fringing will be a result of the lens (it's called "chromatic abberation" and is the result of the optics being imperfect). All but the best lenses have SOME degree of abberation, and bright light with high contrast edges tend to show it more.

It could be diffraction, but if you're looking at 100%, you're just as likely to be seeing the results of imperfect focus, chromatic abberation, diffraction, atmospheric distortion, and who knows what else, all wrapped up into a handful of pixels.

i guess u speak out my question.. when i look at 100%.. the pixel are not sharp enought.

[dcclark]

Originally Posted by scottkiller

i guess u speak out my question.. when i look at 100%.. the pixel are not sharp enought.

So I'll rephrase what I said above -- are you looking at the photo, or smelling it?

Your photo looks just fine, in technical quality, when viewed at a reasonable size. What's the problem?

[Aegea]

IIRC, an object in a photo is generally reckoned to be in focus if the circle of confusion is less than .02 mm (for DX sensors). Since individual pixels on the sensor are generally smaller than .01mm, there will be some blurring at the pixel level. Basically, some fuzziness is to be expected so long as it's only a pixel or three. You might want to take a look at Pixel-Peeper -- Over a million full-size sample photos from lenses, SLR cameras and digicams. for lots of 100% images with various cameras and lenses to get an idea of what is normal.

[OsmosisStudios]

Originally Posted by scottkiller

i guess u speak out my question.. when i look at 100%.. the pixel are not sharp enought.

Can you give US a sample at 100%? And are you sure its 100% and not 200, 300 or 400%?

[scottkiller]

Originally Posted by OsmosisStudios

Can you give US a sample at 100%? And are you sure its 100% and not 200, 300 or 400%?

this is part of it at 100%..
is not sharp due to off focus.. but u can see the hill on right pixel is not sharp as well..


this photo show clearly what the noise i was mention.

Camera: Nikon D3000
Exposure: 0.001 sec (1/800)
Aperture: f/9.0
Focal Length: 55 mm
Focal Length: 55.0 mm
ISO Speed: 200
Exposure Bias: 0 EV