What are the Aperture, Shutter Speed and ISO?

What are the Aperture, Shutter Speed and ISO
via: pixnio.com

Today I want to give you a quick overview of Aperture, Shutter Speed and ISO. Aperture, Shutter Speed and ISO these are the big three when it comes to photography. They can be a little bit tricky to understand it first. So hopefully, I can help you understand the relationship which will make things a lot simplier for you. Daniel Peters over at Fotoblog Hamburg put together this cheat sheet on the big three. And it’ll hopefully give you a visual as I discussed today.

Cheatcard 85x55 300dpi RGB web en CC BY ND - What are the Aperture, Shutter Speed and ISO?
Aperture, Shutter Speed, and ISO Cheatcard

Let’s break this down, we’re gonna go through each one by one. And we are gonna go over the two main functions of each. Now, each of the three controls exposure but on top of that, each of the three also has an artistic control.

Let’s Start with Aperture

Aperture is the measure of how open or closed the iris of your lenses. It’s measured in the term called F-stop. The larger your F-stop number the more closed down your irises which means it lets in less light and thus the exposures darker. This smaller your F-stop number the larger the opening of your iris meaning it’s letting in more light, meaning you have a brighter exposure.

Aperture Shutter ISO 1024x576 - What are the Aperture, Shutter Speed and ISO?

Now there is an artistic use of aperture as well and that’s the depth of field. When you have a low F-stop number meaning you’re letting in a lot of light in. Your exposures brighter you are gonna have a shallower depth of field. This is how you’re gonna have a nice cinematic look in your photos and in your videos. When you have a higher aperture or f-stop number you’re gonna have a much larger depth of field. This is great when you’re shooting some sort of landscape or environment where you want everything in focus.

Second We’ve Got Shutter Speed

The shutter is the measure of how long the shutter of your camera is open and thus allowing light to hit your camera sensor. So when we’ve got a fast shutter 1/2000 of a second for example; it means that you’re gonna be letting in less light. You are only letting in light for 1/2000 of a second which means it’s gonna be a darker exposure than longer shutter speed. Because you’re only letting in that brief amount of light. If we have a longer exposure. For example, 15 seconds that means your shutters open for 15 whole seconds and letting in light for that amount of time. Which means it’s gonna be a much brighter exposure.

Aperture Shutter ISO 2 1024x576 - What are the Aperture, Shutter Speed and ISO?
Shutter Speed

Now that’s the exposure level of shutter but what’s the artistic use well the artistic use is motion blur. When you have a very fast shutter you are essentially freezing time. You could be taking an action photo or some sort of sports photo with a high shutter and it’s freezing that action you won’t see any blur. It’s as though everything is just stopping.

Aperture Shutter ISO 3 1024x576 - What are the Aperture, Shutter Speed and ISO?
Shutter Speed

However, if you have a long exposure you’re gonna start to have blur in your shots. Because the shutter is open wide and every motion that’s happening for the entirety of that shutter being open is getting captured by the sensor. With long shutter speeds, this is how you are gonna get those the light trail photographs or you’re gonna get photos of the stars. It’s when you’re doing these very long exposures that you can do these sort of tricks. But for these, you want to make sure that your cameras on a tripod. Because any motion in the camera is gonna be picked up by the sensor.

Finally, We Have ISO

ISO measures the sensitivity or the post image grain in your sensor. So what this means; when you have a high ISO it means that your camera sensor is more sensitive to light. So it’s gonna be a brighter exposure however it’s also more sensitive to grain. So your image actually breaks down a little and gets somewhat grainy and noisy. Whereas if you have a low ISO somewhere around 100 you’re gonna have a lot less sensitivity which means that your exposure is darker but your image is a lot crisper and less grainy.

Aperture Shutter ISO 4 1 1024x576 - What are the Aperture, Shutter Speed and ISO?

This is something to think about when you’re in dark place and you’ve already adjusted your shutter and aperture and you need to play with your ISO. If you push the limits too high then you’re gonna run into some grain issues when you’re looking back at your footage or your photos. Based on the artistic look that you’re going for it, you can combine any of these three when you want to get your exposure to the right level and you want to adjust your depth of field, your motion blur and make sure that your camera sensitivities at the proper levels. These are the three that you need to use. And you can sort of get a sense of how their relationship works.

Do you have any other information about Aperture, Shutter Speed or ISO? Left your ideas and questions in the comments section below! and please don’t forget to follow kuulphoto.com on Twitter @kuulphoto


Please enter your comment!
Please enter your name here