When to Use a High ISO (+ Tips for High-ISO Photography)

Are there times when a high ISO makes sense? When should you consider using a high ISO? And what ISO can modern cameras handle?

In this article, I’ll explain everything you need to know about high ISOs, including:

• Whether high ISOs are ever a good thing (spoiler alert: they are!)
• Tips and tricks for working with high ISOs for great results
• How to determine the maximum acceptable ISO for your camera
• Much, much more!

Let’s get started.

When (if ever) should you use a high ISO?

Raising the ISO is one of the most common photographic fears. Photographers – especially beginners – are afraid to boost the ISO past 400 or so, lest they ruin images with ugly, unwanted noise.

Ten years ago, these fears were justified. Raising your ISO to 1600 or 3200 was a no-go for the majority of cameras.

But no longer. Things are changing. These days, it often makes sense to boost your ISO to get better images. In fact, the improvements in camera technology have been such that you can now comfortably photograph at ISO 1600, 3200, and even 6400 with most DSLRs, Micro Four Thirds cameras, and mirrorless cameras.

Here are three simple situations when shooting with a high ISO makes sense:

1. When you’re photographing indoors or at night

If you take your camera indoors, or you shoot at night, you’ll quickly run into a problem:

Your images will be dark and lacking detail.

In such situations, you have three solutions:

First, you can widen your aperture. Often, this can help (and it’s the reason why many night photographers and event photographers work with an ultra-low f-stop). But it’s rarely enough.

Second, you can drop your shutter speed. But unless your subject is completely still and you’re shooting with a tripod, you’ll end up with lots of blur. Not ideal, right?

Which brings me to the third solution:

You can raise your ISO.

Will it introduce some noise? Yes. But the noise produced by modern cameras at high ISOs just isn’t that bad; as I mentioned above, you can comfortably boost your ISO to ISO 3200 and ISO 6400 without much loss of quality.

And by raising the ISO, you’ll end up with much brighter images, even indoors and even at night.

2. When you’re photographing fast-moving subjects

The faster your subject, the faster the shutter speed required to render it with zero blur.

For instance, if you’re photographing a runner, you might need a shutter speed of 1/500s. If you’re photographing a moving car, 1/1000s might be more appropriate. And if you’re photographing a diving falcon, 1/3200s is a safe bet.

Unfortunately, even in relatively good light, boosting your shutter speed to 1/3200s will result in a too-dark exposure – unless you raise the ISO, that is.

After all, better to end up with a slightly noisy image than a completely blurry one, right?

So don’t be afraid to increase your ISO when faced with a fast-moving subject.

3. When you’re using a long lens

The longer your lens, the easier it is to end up with blur – because subject movement and camera movement are magnified. So with a long lens, you need a fast shutter speed, just the same as if you were shooting a moving subject.

That’s why boosting your ISO is so essential when working with telephoto lenses; it allows you to boost the shutter speed, too, and capture a sharp image.

Sure, when the light is bright, you can keep the ISO at 100 or 200 and end up with sharp, well-exposed images.

But as the light begins to drop, you’ll need to raise your ISO with confidence. That way, you can capture bright and clear photos at 300mm, 400mm, and beyond.

But doesn’t a lower ISO give better image quality?

Well, yes – and no.

Yes, if you are setting up a studio shot and controlling the lighting. Yes, if you are using a tripod, if you are a landscape photographer, or if there is very strong natural light. Yes, if you don’t have to compromise your shutter speed or aperture settings to expose the shot correctly. A photo taken at ISO 100 will always be significantly sharper and cleaner than a photo taken at ISO 1600, assuming the aperture and shutter speed are the same, and you have complete control over the subject and the lighting.

In every other case, however, the answer is no; a lower ISO will not give better image quality.

Raising your ISO will help you capture a higher quality photograph in many situations. Why? Because it lets you use a faster shutter speed and a smaller aperture to get a sharper result. When creating a technically great photograph – one with minimal blur and proper exposure – getting the aperture and shutter speed settings correct is much more important than using a low ISO.

If you want to know how great event photographers consistently create such bright and beautiful images, it’s not only because they use fast lenses and flashes. It’s because they are not afraid to raise the ISO.

Plus, the look of grain at high ISOs in digital cameras has become more pleasing. The newer camera models have not only reduced the strength of grain (noise) at high ISOs, but they have also created noise that looks more artistic.

ISO has now become a luxury instead of an obstacle. We can photograph in dark areas while handholding the camera when we need to.

Tips for working with high ISOs

Now that you know when and why high ISOs are important, let’s take a look at some easy tips for improving your high-ISO images:

1. When shooting at a high ISO, get the exposure right

Here’s the major problem with photographing at a high ISO:

Raising the exposure in post-production will ruin the look of the grain.

Raising the exposure a small amount is usually okay, but if you are photographing with a high ISO, you need to be even more diligent than usual about exposing your images correctly in-camera.

2. Pay attention to color noise versus black and white noise

You should carefully evaluate how your camera handles the look of noise in your color images. My Fujifilm X100S, for instance, handles color noise exceptionally well. But other cameras don’t do so well with color noise at high ISOs. 

In many cases, however, the problem can be solved by converting the photo to black and white.

Take a look at the image above. This was taken a while back with a compact mirrorless camera at the very extreme end of its ISO range, 6400. Yes, there is a lot of grain, but it still looks good. I prefer not to go over 3200 with my Fujifilm X100S whenever possible, but without using ISO 6400, I probably wouldn’t have been able to capture this image.

3. Test your camera’s ISO to determine acceptable noise levels

While I’ve talked in generalizations up to this point, I do think it’s important to evaluate the ISO capabilities of cameras you own (or cameras you’re thinking of purchasing). You should determine their ISO range, as well as the quantity and quality of noise at different ISOs.

If you’re considering particular cameras but can’t get your hands on a copy to test, there are plenty of in-depth reviews, both on this site and elsewhere. Nearly all of these reviews will discuss high-ISO capabilities, and they’ll often provide sample images.

Of course, if you own the camera already, test it out yourself. Make sure you are using a fast shutter speed and an aperture of somewhere between f/8 and f/16; that way, each image you take is guaranteed to be sharp.

Focus your lens on a nearby object, then take a series of shots, going from ISO 100 all the way to your camera’s maximum ISO. 

Then pull up the images on your computer and zoom into 100% (both in black and white and in color). And decide which ISOs you’re pleased with, and which ISOs you just can’t handle.

If you have a photo printer, I highly suggest printing out your test images to see how the grain looks in real life and to see the differences between images.

It is also important to remember:

If you are regularly printing at smaller sizes, such as 5×7 or 8×10, then you will likely not notice a significant difference between ISO 200 and ISO 1600. But if you prefer to print at larger sizes, such as 20×30, then there will be a noticeable difference. So test it out.

Here are a few examples of noise levels at different ISOs on my old Canon 5D Mark II and Fujifilm X100S:

Noise can be beautiful!

Now that you’ve finished this article, you know why high ISOs can be useful. And you know when you should consider working at a high ISO.

So don’t be scared. Embrace the noise/grain and create some stunning photos!

Now over to you:

What ISO do you generally shoot at? And how high do you go? Share your thoughts in the comments below!