For most of what I shoot, high ISO performance isn’t really much of a concern. It’s rare that I need to go above ISO400, usually. But with today’s cameras having ISOs that go up into the multiple hundreds of thousands, what’s the point if going that high degrades the image so badly that it’s pretty much unusable?
That’s the topic that music and sports David Bergman explores in this video. Cameras and their crazy high ISO values, what’s the point of them and when and why you might want to use them.
ISO, contrary to the film days, is not “sensitivity”. It’s gain. It’s an amplification of the signal coming from your sensor, based on the light that hits it after it’s hit it. Increasing your ISO with digital cameras reduces dynamic range and adds noise. So, while it’s best to try to keep your ISO as low as you can get away with for best results, sometimes you really do need to ramp it up a little. Perhaps higher than you’d normally accept in order to be able to get a sharp and well-exposed photo.
Is it really a big deal to ramp it up high? Well, a lot of the time, it may not be. As David explains, noise is usually only of concern to us photographers. No client is ever going to pixel peep our images the way we do. And if the photo you’re shooting is only going to social media, then you’re not going to see that noise when it’s scaled down to Instagram or Facebook sizes anyway.
Having your image well composed, in focus and without a whole mess of motion blur is far more important to most viewers than the amount of noise present in the image.
For me, I mostly shoot with flash or in pretty bright conditions. And when I’m not, my subjects often aren’t moving so I can stick the camera on a tripod and use a long exposure, so I usually don’t need that high ISO. But occasionally, I do. Sometimes a little noise can actually even add character to your images. Nighttime street photography, for example, can often benefit from a little noise – Especially if you’re converting to black and white – and I’ll often find myself shooting at ISO 12,800 or even higher whenever I’m doing it.
Don’t be afraid to bump that ISO up high if you need to. A well-composed and sharp but noisy shot is much better than having no shot at all.