PHOTOGRAPHY 101: ISO, APERTURE, SHUTTER SPEED, AND MORE
July 28th, 2021
If you’re here, there’s a good chance you’ve decided to pick up photography. Congrats! Welcome to one of the most fulfilling, fun, and memorable hobbies out there (in my humble, very unbiased opinion). Maybe you’ve got a fancy digital SLR, perhaps some sort of retro film camera, or maybe just a cellphone and a dream. Whatever you have, there is definitely some basic photographic knowledge you need to take your images to the next level – whether you want to be a professional or if you’re just looking to take some cool photos for your Instagram the next time you’re on a hike. Modern cameras (even cellphones) have a multitude of buttons and settings that can be a bit daunting to navigate at first. I definitely panicked the first time I picked up a camera, and shot exclusively in “automatic” mode because I had simply no clue what “aperture” or “ISO” (or really anything) even meant. But as smart as our technology is, the best photographers want to have complete control - or at least a little bit - over their settings. So in this blog post, I’ll introduce you to some of the basic camera settings, and hopefully instantly give you a deeper understanding of how to start taking better photos.
The photographic triangle of success is a reminder that most photos are a balance of shutter speed, ISO, and aperture.
At its core, every photo is about balancing three things: ISO, shutter speed, and aperture. Shutter speed is the most intuitive - it describes how long your film or sensor is exposed to the scene you’re photographing. A short shutter speed (let’s say, 1/500th of second) means light is entering your camera for a very quick amount of time, which is ideal if the scene you’re photographing is already bright. As it gets darker, a longer shutter speed (2 seconds, for example) allows your camera to visualize a scene for a longer duration and soak up more light. In general, the brighter your scene is inherently, the shorter your shutter speed needs to be. There are some exceptions to this rule – for example, if you want to capture the flow of moving water in a smooth, silky-looking way you’ll need a longer shutter speed no matter what time of day - but that’s a whole other blog post for a different time.
I used a short shutter speed (1/200 secs) to photograph the train in motion on the left image, especially since it was broad daylight. On the right, I used a much longer shutter speed (15 secs) to capture the movement of an Iceland waterfall on a dark and gloomy afternoon.
Next up is ISO. Technically, ISO stands for “International Organization for Standardization”, but to be perfectly honest I had to look that up two seconds ago and it really doesn’t mean anything. In photographic terms, ISO refers to your camera’s sensitivity to light. When you’re photographing a bright scene, your camera doesn’t need much light sensitivity, and a low ISO (like 100 or 200) will do the trick. But as a scene gets darker, it becomes harder and harder for your camera to pick up on that latent light – even with a long shutter speed. Therefore, your camera will need a higher ISO (such as 1000, or even as high as 32,000!). However, this setting comes with a pretty massive caveat. While modern cameras are getting better, in general, shooting with a high ISO introduces noise into your photo – leading to images that are blurry, pixelated, and all-around not so good looking.
While I was in Africa, I was able to snag this image of a couple lions on the prowl. But because it was late at night, and very dark, I had to use a very high ISO just to see anything. I got the photo - but sacrificed some quality and the result was a grainy, not-so-sharp image.
The last of corner of the photographic triangle of success is aperture – which is my favorite, and in my opinion the most important. Aperture describes how open the lens of your camera is, which in turn controls not just how much light can pass through to the sensor but also where your camera can focus. If you can imagine your camera as an electronic replica of the human eye (which it kind of is), aperture would define how dilated your pupils would be. A larger aperture would suggest some very dilated pupils, which are wide open and capturing a ton of light. While the concept itself is not terribly complicated, here’s where things get a little tricky. In most cameras, aperture is measured in f/stops ranging from something like 1.4 to 28. However, f/stops are actually fractions – and the numbers refer to the value of the denominator. An f/stop of 1.4 actually means “f / 1.4”, which is actually larger than an f/stop of 28 (f / 28). In short, smaller f/stops refer to larger, wide open apertures that capture a ton of light, while larger f/stops do the opposite. As with shutter speed and ISO, setting your aperture will depend on the brightness of the scene you’re interested in.
But as I mentioned, aperture serves a dual purpose in dictating where your camera focuses (known as “depth of field”). To help visualize things, do me a favor and place your hand six inches in front of your face. If you focus just on the palm of your hand, you’ll notice that the background behind it actually becomes blurry. Similarly, if you focus exclusively on the background, you’ll find that now your hand is blurry – despite the fact that it’s still less than a foot from your face. And if you begin to move your hand away from your face, you’ll notice that at a certain point both it and the background will be in focus. Just like your eyes, your camera has the power to focus on large areas or just specific parts of a scene, and this is all controlled by the aperture. A larger aperture (which, if you remember, means a lower f/stop like 1.4 or 4.5), allows you to focus on a very specific section of a scene, and leave the rest blurry. A smaller aperture (a higher f/stop like 9.0 or 18.0), will allow you to keep more of the scene in focus. As you can imagine, a larger aperture might be super useful for portrait photography, while landscapes often require a smaller aperture.
To focus exclusively on the chameleon in the image on the right, I used a very wide aperture (f/2.8) which completely blurred the background. In the photo on the left, I used a relatively closed aperture (f/22) which ensured that both the city and the rocks in the foreground were all in focus.
As I mentioned, as a general rule of thumb every photo balances shutter speed, ISO, and aperture to create a well-exposed look. You want to create a long exposure of some moving water? Maybe you’ll use a long shutter speed, decrease that ISO, and close that aperture. You want to take some portrait photos of your friend on a sunny day? Open that aperture nice and wide, shorten that shutter speed, and throw that ISO down to 100. Shutter speed, ISO, and aperture are really the three key settings for every photo, no matter what kind of photography you’re into. Truly understanding which settings are appropriate under what conditions requires trial and error and a ton of practice – so just get out there and have some photographic fun!
Bonus Tip: The “manual” (M) mode on many digital cameras allows the users to control EVERYTHING about a photo. But if you’re not quite there yet, there are other modes that allow you to tweak some things, while letting the camera figure out the rest. For example, the “aperture priority” (Av or A) mode allows you to manually set the aperture and ISO, and your camera will then choose an appropriate shutter speed to balance your image. The shutter priority mode (Tv or S) will let you select the shutter speed and ISO, and your camera will adjust the aperture accordingly. Playing around with some of these modes is a great way to practice and get a feel for the right settings under different conditions!
Thank you for reading! I hope you found this helpful. Don’t hesitate to email or contact me if you have any questions. To stay updated on when these blogs come out (and to see more of my photos) please follow me on Instagram, Twitter, and Facebook via the icons below.