Please, would someone care to explain to me...

LaFoto · May 3, 2004

... what "colour noise" means - or "noise" in a photo at all?
I'm finding this expression over and again here, but since the English language is not my native language, and photography terms are "alien" to me even in MY language (German), I'd need someone very patient to detail this out for me in very simple words.

Who dares?

ceno2000 · May 3, 2004

it is kinda like this
have you wver watched a tv show that had either 1.bad reception and was a little fuzz "pixilated" around the edges or 2. a cable/satalite program that is being stole/pirated/orbad reception abain and you get all that staticy crap everywhere? i thimk it is kinda like that
there is not enough info there so it all blurs together and makes little fuzzies
if i am wrong please explain it to the both of us

ksmattfish · May 3, 2004

Noise is to digital what grain is to film, at least visually.

LaFoto · May 3, 2004

Oh. Thank you!
That sounds reasonable to me. "Noise"="grain".
But then the "photobug" speaks about "noise" in his "Nocturnal" photos over in the gallery where I can't see it! Am I blind? Must be...

markc · May 3, 2004

Here's some examples of noisy pictures and the same after they've been "cleaned", so you can see the difference.
http://www.neatimage.com/examples.html

oriecat · May 3, 2004

Not disagreeing with Matt, as that is exactly how I would have explained it, but isn't it a bit too simplistic or misleading? Often grain is desirable in film pics, I really like grainy pics myself, whereas noise is pretty much always bad? Do people ever deliberately shoot for noise?

markc · May 3, 2004

Grain is now seen as an artistic choice, but I think early on the goal usually was to reduce it as much as possible, much as noise is today. I wouldn't be surprised if down the road noise is used more often as an artistic method, once it's no longer quite so common. It's similar to how pixelization has been treated.

photobug · May 3, 2004

Lafoto- it's hard to see in the pic I posted because a) I tried to hide it by messing with the colors, b) I reduced the size & resolution of the pic & c) because it's so dark.

Here's a crop of the lower right corner of the Blue & Green Bridge pic. Full res crop. In this case the color noise was caused by the pic being underexposed. When I tried to correct it the gradation between the background light and the sky went blotchy instead of being a smooth transition. This is color noise:

And here's an example of digital noise (like film grain):

Hope that helps.

Digital Matt · May 3, 2004

oriecat said:
Not disagreeing with Matt, as that is exactly how I would have explained it, but isn't it a bit too simplistic or misleading? Often grain is desirable in film pics, I really like grainy pics myself, whereas noise is pretty much always bad? Do people ever deliberately shoot for noise?

I don't think noise is always bad. If you are comparing noise and film grain and saying they are equal, then how can you say that film grain is desireable, and digital noise not?

Here's a digital shot I took where I intentionally increased the noise. I think it works in the same way that film grain works, when it works.

oriecat · May 3, 2004

Digital Matt said:
I don't think noise is always bad. If you are comparing noise and film grain and saying they are equal, then how can you say that film grain is desireable, and digital noise not?

I said I felt the equation was misleading, even tho I agree it is the easiest way to define it. And I didn't say it is bad as a statement, I asked a question. It wasn't rhetorical. I actually wanted to know how it is viewed, because I don't claim to know. That was just the impression I had...

LaFoto · May 5, 2004

Oh, I'm suddenly realising that I've never come round to say Thank You to all of you who set out to explain to me what "colour noise" means.

THANK YOU

And giving me examples, too - very informative.
So I see that it CAN be something desirable, but in most cases it is not.
And it's what "grain" is on film.

And you can REDUCE it via PhotoShop?
Ah, OK. I accept that you can but won't even ask ONCE how... I still understand SO LITTLE about PhotoShop...

ksmattfish · May 5, 2004

markc said:
Grain is now seen as an artistic choice, but I think early on the goal usually was to reduce it as much as possible, much as noise is today. I wouldn't be surprised if down the road noise is used more often as an artistic method, once it's no longer quite so common. It's similar to how pixelization has been treated.

I agree with this. When new technology arrives, the norm is to try and make it perfect. People have been striving to reduce grain for a century, although some have embraced grain, and use it in their work. I assume that the same will happen to noise. It's not very popular now, but I imagine that more folks will start using it in a visually stimulating way.

My response was simplistic, but I feel it reflects the popular conception (which is too simplistic) that "grain is bad". You could replace the word "grain" with "digital noise".