The Art of War on Noise

Overuse of noise reduction software results in over-soft, strangely glowing, almost cartoonish images. Sometimes that works. Sometimes.

Those of us who use the higher end of our camera’s ISO range face two critical questions: Whether to deal with the inevitable noise (heavy grain and color irregularities), and if so, how to deal with it.

Many people start with the second question, asking, “What noise reduction software should I use?” That’s putting tactics before strategy, and as any fan of Sun Tzu’s Art of War can tell you, “Strategy without tactics is the slow path to victory; tactics without strategy is the noise before defeat.”

I’m going to go with SunTzu’s judgment on this one, and start with the bigger picture.

Most digital cameras produce increasing amounts of noise as we crank up the ISO dial. The image becomes grainy, with flecks of oddball colors thrown in for good measure. The noise worsens in underexposed areas, particularly when we lighten them in post-processing.

This is what serious noise looks like. Check out the background and the underexposed areas.

Reducing the noise allowed me to lighten this image. In this case, the loss of sharpness from noise reduction seems worth it to me, as I found the graininess distracting. In fact, I think this image actually looks sharper, even though, technically, it is not. This is some of the magic of Noise Ninja, described below.

Most digital photographers have seen noise, because most digital photographers enlarge their images to “100%” or bigger on bright, high-resolution computer screens. For some cameras, that’s like looking at a 40” print. If the print were backlit.

Unless you regularly make 40” backlit prints, you might consider this the first question in your noise analysis: How does the noise look at the intended print and/or viewing size?

For disciplined photographers, the first question is also the last, because the image that looked grainy and strangely colored at 100% looks mighty fine as an 8”x10” print or as monitor wallpaper. I think you should only worry about noise if it significantly degrades the quality of your photo in its final size at a proper viewing distance. Put your nose up against Moonrise Over Hernandez, New Mexico and you see grain, at least until the guards wrestle you to the ground. Step back and you see a beautiful image.

With today’s excellent cameras, careful exposure can limit the apparent noise in an image – if you don’t have to lighten the image in post-processing, much noise will stay hidden.

But when you find the amount of noise in an image excessive, remember that reducing noise can also degrade the quality of your photo. Generally speaking, noise reduction software reduces noise by slightly blurring non-edge areas of the image. The end result could range from a slight softening of the image to a cheap and heavy-handed retouch job (which is how I often use noise reduction for older people and teenagers).

Sharpness does not always improve an image.

Sometimes I use noise reduction software the way I used to use diffusion filters, to keep overall line sharpness while blending and softening broader areas of skin. Don't think this looks sharp? Move back a foot or more and look again.

I do not use in-camera noise reduction, because I want to keep my options open. I use Noise Ninja, which the company can explain better than I. I chose Noise Ninja after reading several online comparisons of noise reduction plug-ins.  I did not understand most of the reviews, but Noise Ninja typically got high marks for ease of use, and it offered pre-set adjustments for my cameras. “Easy” gets my attention.

For several years, I applied Noise Ninja to every image shot at ISO 800 or higher. It seemed like magic. To this day, I’ll apply it to images at any ISO, if I am trying to fix a teenager’s complexion. But for the past few months I’ve been more judicious. I rarely print images, and for the ones that appear in newspapers, I can assure you noise is the least of my problems. From a proper viewing distance, apparent sharpness improves the impact of the images, and trumps my pixel-peeping anxieties.

I often say that when your only tool is a hammer, all of your problems start to look like tiny glass figurines. Just because I have good noise reduction software does not mean I have to use it all the time. But when I need it, it’s good to know that Noise Ninja is available, and easy to use.

Without noise reduction software, much of my theater and dance work would not be possible.

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