Noise; A Train of Thought in 3 Parts
September 26th, 2006
- A certain amount of noise can improve the performance of non-linear systems. This sounds like nonsense, but it’s not when you stop to think about it. For example, B&W photographers have long known that a grainier image can often look sharper than a grainless one. If you are interested in the science behind it, this guy has written some articles about noise that are entirely over my head. His book, which was discussed on Science Friday recently, sounds like its more my speed. He also has some challenging thoughts on the diminishing importance of the comma.
- Although a lot photographers seem to be pursuing noiselessness, noiseless photos fail to satisfy me on some deeper level. I can appreciate the technical mastery, or least the amount of money, involved in creating a noiseless image, but I don’t find them particularly interesting. I’m not the only one, but I’d argue that as a group, photographers don’t know nearly enough about the roll noise plays in the success or failure of a photograph. For example, can you to a certain extent hide blown highlights by adding the right amount and kind of noise?
- I’m pretty happy with the noise qualities of the D80. You can check out a whole bunch of test shots and comparisons over at Dpreview. I haven’t used the D80 at 1600 all that often yet, but I’m pleased with the results so far.
ISO 1600
Crop of ISO 1600 image
September 26th, 2006
Hi Matt,
I agree an image needs some visual “grip”. Too clean and it looks plastic. Specially in low light situations where there’s very low contrast to define detail. It’s amazing how people accepted film grain and now is very picky in digital noise. If you work in raw, the chroma noise disapears in processing and you only get luminance noise, very film like looking (at least on my cameras). This shot you put here looks like taken in jpg, right?
September 26th, 2006
It’s a RAW shot, but it’s significantly underexposed to maintain some info in the highights. That underexposure increases the chroma noise. Even taken as a near worse case scenario, this looks better to me than NPZ.
September 26th, 2006
You used Camera Raw? It tends to balance chroma noise and converts it to neutral very well. Maybe this shot pushed the limits a bit. Anyway it’s very acceptable noise level.
September 26th, 2006
I agree that noise in a non-linear system like film can be useful. However, since digital camer sensors are a linear system, I don’t think its as useful.
I hate color noise, but I don’t mind film grain. In cases of large amounts of noise, I’d rather see the image converted to B&W to make the noise a little less distracting… or.. noise reduction with the addition of more natural looking film grain to take its place … but that’s just me.
September 27th, 2006
I get your point, but in the case of photography as in audio recordings, regardless of the recording medium our perceptual abilities are non-linear.
I’m not sure that I hate chroma noise. I’m not entirely sure that I agree that chroma noise doesn’t look film like, but in any case, until chroma noise starts to affect color balance, it doesn’t bother me.
September 27th, 2006
Flaneur, I shot in RAW, but I processed this with Nikon’s crummy picture project plugin for PS, which doesn’t allow any changes other than wb and exposure during conversion. In short, this is probably about as bad as it gets.
September 27th, 2006
Right, but when you apply your perceptual abilities, you’re applying them to something that was non-linear, but has since been normalized into a linear representation.
September 27th, 2006
I’m not sure that changes the impact noise has on our perception of sharpness. We probably need beer to figure this one out.
September 27th, 2006
Why not to use Camera Raw if you use Photoshop? Oh, I get it, it’s not included yet, right?
September 27th, 2006
Yeah, Camera Raw doesn’t support the D80 yet.
September 27th, 2006
Raw Developer supports the D80 (as I can see a Mac there)
http://www.iridientdigital.com/
January 10th, 2008
Of course noise is an integrated part of the image - noise abounds, but when people start getting bent out of shapr because they see noise in ultra low contrast images taken at 1600 and 3200 ASA, they should take a deep breath and the get a life. At the risk of sounding like an old fart, It was not so long ago that 2475 was the only way to go for 1600 speed and even if you slow processed it in Definol, it still had grain to wazoo. Embrace the noise - I love it.