There are three factors you need to assess when shooting in manual mode (if you’re a professional photographer or you want to be a professional, it’s important to know what these things mean). You have to learn how to balance the three of these properly, because if you change one setting, it will affect the exposure of the photo, which means you will have to change another setting.
Aperture
Aperture is my favorite setting to use because it can change so much about the photo. I’ll explain. Aperture works kind of like the pupil of your eye. The wider the aperture (the smaller the number), the more light is let into the camera. The narrower the aperture (the larger the number), the less light is let into the camera. There’s another thing to note about aperture, though. If you set a wide aperture, say f/2.0, fewer things in the image will be in focus; the focal point will be a lot more specific. But if you have a narrower aperture, say f/10, more things in the frame will be in focus.
The photos above show a difference in aperture. The background in the photo to the left is more blown out, or more blurry. This means that the aperture is wider. The photo to the right has a slightly narrower aperture which allows you to see the background a little more clearly.
If you want to take a portrait of somebody, you’ll want to use a wider aperture. This will blow out the background and any foreground, and bring attention to the person.
If you want to take a picture of a beautiful landscape, a narrow aperture will be a better choice.
Shutter Speed
Shutter speed is basically just the speed at which the photo is taken. The shutter speed is measured in seconds or fractions of a second. So a shutter speed of 1/80 means one-eightieth of a second. 1/500 means one five-hundredth of a second. The slowest shutter speed that most cameras offer is up to 30 seconds, but it’s not often that you would need that kind of exposure.
The photo above shows the same situation at different shutter speeds. The pinwheel to the very left has a fast shutter speed because it froze it in time. The pinwheels to the right were taken using slower shutter speeds which shows the motion of them. Motion blur can be a good thing. Many photographers use slower shutter speeds to make moving water more smooth or to show propeller movement at an air show.
Let’s say you’re taking a photo of a landscape. You will want a narrow aperture. In using the narrow aperture, less light is getting into the camera, so you will want to keep the shutter open for longer. But like I said, the longer you keep the shutter open, though, the more likely you are to get a blurry photo. That is why landscape photographers use tripods and shutter remotes, to reduce the amount of camera shake.
Portrait photography usually doesn’t require such a narrow aperture, which means you can have a faster shutter speed.
ISO
ISO stands for International Organization of Standardization. I don’t know why it’s called ISO instead of IOS, but that’s just how it is. ISO is the sensitivity of your camera’s sensor (the photo above shows what a camera sensor looks like). So a low ISO means that your camera will be less sensitive to light. You want to use a low ISO of 100 in bright situations. An ISO of 800 would be used in a very dark situation.
Warning!! You lose photo quality when you use a higher ISO. That is why you need to use the lowest ISO required for the situation. The two photos below show how you can lose quality when using higher ISO’s. The photo on the top was taken using a lower ISO. It is not as exposed as the photo below it, but you can see the photo below has more noise or grain. A little grain isn’t a bad thing. You just need to decide what works best for you as a photographer.
Higher end cameras can achieve higher ISO’s, but it is still important to use the lowest ISO possible for the situation.
Don’t be scared of using a high ISO. Push your camera to it’s limit to see what it is capable of.
Balancing All Three
Now that we understand all three of the settings, we need to learn how to use all of them together.
Let’s say the sun has set, but there’s still a bit of sunlight left. We want to take a picture of a meadow with some trees. The settings I would use would be as follows: Narrow aperture of f/10, slower shutter speed of 1/30 or even slower, and a medium ISO of 400.
Now let’s say we’re taking a portrait of somebody outside on a sunny day, but the ground is covered in snow. The snow acts as a giant reflector which will allow a lot of light into the camera. My settings would be approximately a wider aperture of f/3, a fast shutter speed 1/500 or faster, and a low ISO of 100.
Of course, these are just approximations. You won’t know the exact settings you need until you’re in the situation.
If you look at these photos here, you can see that the one to the left is under-exposed, the one in the middle is exposed properly and the one to the right is over-exposed. Each setting is unique on its own, but they all play a part in exposing your photo.
If you haven’t starting shooting in manual mode, it’s time you start! Shooting in manual gives you control over the situation. Auto mode in cameras are pretty decent these days, but if you want to take your photography to the next level, practice using your own settings. It’ll be difficult at first, but once you learn, it’ll be second nature!
Δ Abbi