A very beginner question: what is "noise"?

[MedCruise07]

I just started reading these boards and have come across a few references to "noise"--can someone please explain (in beginner language)? Thanks!

 

[Tuffcookie]

When you take a picture that looks very grainy...that's noise!

TC

 

[caniswolfie]

To describe noise in a digital photograph, I think it looks a lot like the "snow" on a television when there is interference or a bad signal. A photograph will appear rough even in places you know is a smooth color or surface. There will be a lot of little dots of the wrong color or white/black in it when you zoom in on the photograph.

This is usually caused by taking a picture at a high ISO setting (a camera setting which allows you to take a picture at higher shutter speed and/or smaller aperture). The higher the ISO setting the more noise you get in the final photograph.

Noise usually lowers the quality of a picture somewhat depending on the image you are trying to take (there are some photographers that intentionally use noise in some pictures for a certain mood or effect).

Anyone can feel free to add to my description or correct me. I'm not good at explaining things too well in written form.

 

[Khokhonutt]

Look very close at the drums and even the girl's hair in the lower left corner of the picture.

See the graininess? (not sure if that's a word):

Here's the same picture after touching it up in Noise Ninja:

It's very subtle at this resolution, it's a little more obvious at full res (dialup beware):

Unedited (very large)

Edited (very large)

Hope that helps.

 

[Amy]

Like the others said, noise is graininess in the photo, not to be confused with a photo that's out of focus. It's caused when the ISO is set too high (usually anything over ISO400). In my case, I have a Canon S3 IS, and because my DS's are in marching band, I'm taking pictures at night under football field lights during competitions. I use my "sports" setting to stop the action, and my camera bumps up the ISO automatically so it can use a faster shutter speed, and I end up with noisy photos.

Here's a noisy shot; look at the grain on the black uniforms:

This one has been run thru Noiseware; notice how much more crisp the black uniforms look. Even the field looks a tad different.

 

[weloveprincesses]

Even though I'm not op, I just wanted to say thanks to you guys for taking the time to post this. I used to know this sort of stuff, but after two kids and eight years of taking basically PnS stuff, I'd forgotten all of it. This helps out a lot to read these boards. I'm pretty intimidated by all of the jargon!

Thanks again,
Maggi

 

[handicap18]

Those aren't very noisy...

This is a noisy picture:

Ok so you can't quite tell as much at this size, but when its bigger, it is AWFUL.