Understanding Exposure

(London Thames Festival)

Today I want to talk about exposure. It’s a crucial part of photography, and really important to understand if you want to be able to photograph in manual mode (which will ultimately make your photos better).
I know it can seem daunting learning about exposure, especially because it all sounds so technical.
I’ll try my best to keep it simple and easy to understand, and as non-technical as possible.

Photography is all about light - an image is produced by light reaching your camera’s sensor.
So if light is all that photography is you should understand how it works, and how to get the right amount of light reaching the camera’s sensor.

There’s something out there called ‘the exposure triangle’. It refers to the three main elements that influence exposure: ISO, aperture, shutter speed.
They all relate, so if you change one of them it will impact the other two. So keep that in mind.

ISO indicates how sensitive your camera is to light. The ISO settings start at 100 (which means it’s not very light sensitive), and go up to 51200 for some cameras (very very light sensitive).

Aperture refers to how wide your lens is open, how much light will come in through the lens.
If your aperture is wide open it lets in lots of light.
Don’t get confused with the numbers by the way. F stands for aperture, and the smaller the F number is the wider open your aperture is.
So for example f/2.8 means that your aperture is very wide, and therefore lots of light comes into the camera.

Shutter speed is the speed with which your camera takes a photo.
It simply means how fast the shutters of your camera open and close again, which determines how much light reaches the sensor.
1/15 of a second is a very slow shutter speed, whereas 1/4000 sec is pretty fast.

You can only benefit from understanding all three elements, because it means you’ll be able to control them.
This is so important as it gives you the ability to work in manual mode.
You can then decide what you want your photo to look like in the end in order to communicate what you want to say.
I believe that you should usually know what outcome you want to achieve when taking a photo.

For example: If you’re photographing a dancer - emphasize movement.
You can do that using blur - to achieve the right kind of blur you have to set your camera manually.
Blur can be achieved through using a slow shutter speed. But then keep in mind that a slow shutter speed means that lots of light is reaching your camera’s sensor.
You don’t want your photo to be overexposed though, so you will need to cut down the amount of light coming into your camera elsewhere (with ISO and aperture).

This is just an overview to help you understand how exposure works, so I won’t get into more detail just now.
I’ll be writing more posts on exposure later on, though, simply because it’s such an important part of photography and so crucial to understand.
It’s basically what makes a photo.

So stay tuned for more to come. I hope this post helped to clear your mind, and to take the fear out of exposure.

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  1. You're little tutorials are so helpful--they definitely make me want to break out my camera more often!

    1. Thank you, Kate. I'm glad it makes you want to photograph more often. :)

  2. For some reason, I always find it overwhelming to have to adjust all of those settings.It seems to take time to figure out which settings will work for what photo. I guess I just need more practice :) But this is again a great tutorial!

    1. Thanks, Colette. It really is all just about practising. I remember what it was like for me in the beginning - over time you'll get more confident with the settings, and you won't have to think about it anymore. So do keep taking photos. :)

  3. This is unbelievably helpful! I just bought my film camera less than a year ago and am still trying to figure out the perfect settings. thank you! :)

    1. By the way your photos are beautiful. I took a look at your portfolio and love your work!

    2. Thank you, Carrie! That's encouraging. :)