Let’s Talk About ISO

Estimated reading time: 4 minutes

What is ISO? Do I need it? What is it anyway and should I even care?

For someone just starting out with cat photography in Auto mode on a DSLR, mirrorless, or smartphone camera, ISO might not be a concern. However, as your passion for capturing your feline family grows, you will naturally want to expand your photographic skills.

That’s where ISO comes in – it’s an essential part of your growing skillset.

• ISO adjusts your camera’s light sensitivity.

What does ISO mean?

Let’s start with a short (and helpful) description of ISO.

If you look, you will find a lot of definitions and explanations online so I saved you a job by finding the best explanation (I think), and the easiest to understand.

The founders of the International Organization for Standardization (the group that created ISO standards for cameras) tried to find a universally understandable acronym, but it proved difficult with so many member countries and languages.

Instead, they chose ISO as a shortened version of the Greek word “isos” which means “equal.” This reflects their goal of creating international standards that would be equal and consistent across the globe.

ISO/Google

How do you measure ISO?

Light is measured though your camera lens. This might seem obvious but cameras have so many buttons, bells and whistles that it is easy to get confused.

You adjust the camera’s sensitivity to light by changing your ISO. The lower the ISO number you set the less sensitive your camera is to light.

With all cameras, not just those used for cat photography ISO, starts at 100 and goes to 6400 on the cameras most of us cat lovers will use. A good place to start your explorations, especially using A or Av mode (which I love) is with ISO 100 or 200. This is great for a bright day outside, on a catio or a close to the window portrait.

Then start changing your settings and see what happens!

How do I set my ISO?

The best way to become more confident about setting your ISO is to play with your own camera. ISO will be adjusted with a dial, or as part of your camera menu screen. Check your manual if you are not sure or refer to your camera company’s web site.

Give yourself permission to fool around and play with your ISO. See what happens as you change the light sensitivity, in a spirit of exploration and fun.

This photo has an ISO of 200 and it is too low.

Raising the ISO to 800 gives a better picture.

Low ISO (100-400)

This is like turning down the sensitivity. Great for bright sunny days outdoors or well-lit rooms. It creates clean, crisp photos with little to no grain (also called noise). However, you might need a slower shutter speed which can blur moving cats. (1/250 is a good shutter setting for moving cats).

• The Importance of Light in Cat Photography

Medium ISO (400-1600)

This level of ISO turns up the sensitivity in your camera. It’s good for cloudy days, indoors with some light, or action shots where you need a faster shutter speed to freeze your cat’s movement. There might be some ‘noise’ also known as grain, but this shouldn’t overpower the photo. It is up to you, the photographer to decide how much noise suits your purpose.

What is Digital Noise? “Noise is a grainy veil in a photograph, obscuring details and making the picture appear significantly worse.”

Photography Life

Successful portrait of Thomas ISO 400

Here you are really pushing your ISO (sensitivity) to cope with low-light situations. A high ISO will be great for capturing indoor cat naps or playful moments in the evening but, you can expect to see more digital noise, which can make photos look textured or rough. It is up to you to decide how you shoot and how you adjust your own ISO.

I could pack my short post with pictures to demonstrate each ISO but I know you will learn more by grabbing your camera or smartphone and doing something yourself. So get out there, tinker with your ISO and make this your first step out of Auto mode!