Saturday, November 05, 2005

Noise Annoys

Cruise through any news group related to digital photography and you'll find they all have one thing in common no matter which camera the group is dedicated to -- the largest threads will be about High ISO Noise and how it is a problem that needs to be eliminated at all costs.

It always makes me laugh that when you get two people from different dSLR camps together -- Nikon and Canon for example -- the easiest way to start a flame war is to mention High ISO Noise and that one camera handles it better than another.

According to Canon enthusiasts, Canon cameras handle image noise better than Nikon does, particularly at ISO values above 800.

Well, it depends on what your definition of "better" is. Canon images shot at high values (800, 1600, 3200) seem to exhibit less noise than Nikon's because Canon uses a lot of in-camera noise reduction (both user-selectable and built-in). As a result, Canon images shot at high ISOs look "soft" because of all the image processing the camera does. Nikon, on the other hand, does less image processing in-camera, preferring to let the photographer handle it in post-processing. As a result, Nikon camera produce images that exhibit more noise at the same ISO values.

Where this obsession for noise-free digital images comes from I'll never know. I suspect it's because the proponents of noise-free images have never shot film. They don't know what film grain looks like or what purpose it serves.

Also, how often do you need to use high ISO values anyway? In more than 30 years of photography, I've generally never needed film faster than 400 ISO. Granted, when shooting weddings, ISO 800 speed film comes in handy in many situations. But the only time I've used anything faster was when I was experimenting with a new film.

I often wonder how much the people who complain about High ISO Noise actually shoot at high ISO values. Have they ever shot ISO 3200 film? If they did, then they'd know what grain looks like!

I think Bjorn Rorslett put it into perspective beautifully in his review of Nikon's D2X camera:

For some strange reason, inscrutable in a true Oriental fashion, photographers (or more likely, gearheads masquerading as photographers) have become obsessed with "noise" at astronomically high ISO speeds, even if these are outside the approved camera settings. Each to his own, but I frankly cannot see the relevance for some of these heated debates. People should try faster lenses or make other improvements to their technique before complaining about noise at 3200 ISO equivalency. Or try 3200 ISO film, that'll teach them a lesson in what's relevant.

Digital images need a bit of noise in them. It helps prevent that "plastic" look you see with a lot of images. Too much sharpening, noise reduction and other post-processing tricks tend to make digital images look too perfect and not very realistic.

Besides, coming from a film photogrpahy background, I'm used to seeing some film grain (the analog equivalent of image noise) in my images. It gives them depth and character.

I think the "gearheads," as Rorslett correctly calls them, should worry less about High ISO Noise in their images and more about learning how to use their cameras to produce better pictures.

1 comment:

Jet Tredmont said...

I shot film for many years, and do know what film grain looks like. I rarely loaded my camera at over 400 iso for two reasons: one because the grain became highly annoying to me above that, and two because I'd end up on a 24-frame roll getting 4 pictures which needed the high-speed film and 20 that were ruined because of the high grain and would have been great pictures if I'd used iso 200 or 100.

Okay, 1 and 5. Okay, maybe less. But still.

With my Canon I have several 1600 iso shots that I treasure, and I didn't have to sacrifice five other shots to get them. I also have many beautiful iso 100 shots.