Written by Louise Wright
So, you’ve decided to give photography a go and have invested in an awesome new camera. Now there’s only one problem – you’re not too sure what aperture, ISO and shutter speed mean! Well, that’s what the CameraPro team is here for. Let’s get to it.
The key thing to understand with photography is that it’s all about LIGHT. And using the exposure settings on your camera will control how your camera sees and processes the light that comes in via the lens. Makes sense, right?
Now, the three key elements of exposure are ISO, Shutter Speed and Aperture. Using these three settings will control how your photographs look, and knowing how to control them will help you get the most out of your camera and create interesting and beautiful images.
So, what do ISO, Shutter Speed and Aperture actually mean?
Essentially, ISO controls how sensitive your camera’s sensor will be to the light coming in via the lens.
The lower the ISO number, the less sensitive your camera is to light and the finer the grain in the image (also called ‘noise’).
ISO can range from 50 – 102400, however not all cameras will have a range this large. If you’re wanting to do a lot of low light photography, then ISO range and capability is something you should consider when buying your camera.
What ISO should I use?
As a general rule of thumb, it’s best to keep your ISO as low as possible (generally ISO 100) whenever possible. This is because the lower the ISO, the less grain will be visible in the image.
Of course you should always bump it up when required - a grainy photo is always better than an out of focus photo!
Below are examples of when to use a low or high ISO.
LOW ISO – eg. ISO 100
This is generally used for:
HIGH ISO – eg. 3200
Generally used in darker situations when not as much light is available, to get faster shutter speeds, such as:
Simply put, shutter speed is how quickly the camera will open and close its shutter.
Shutter speed range generally goes from 30 seconds to 1/8000th of a second or sometimes even faster! As with ISO, not all cameras will have this exact shutter speed range, and if you’re planning on using a lot of fast shutter speeds, shutter speed range is worth considering when buying a camera.
It’s also worth noting that the shutter speed is limited to the style of camera – for example DSLR cameras can have up to 1/8000th second shutter speed because of the mechanical shutter. Other cameras such as mirrorless cameras can have incredibly fast shutter speeds such as 1/32000th second with the electronic shutter.
What shutter speed should I use?
Generally use a fast shutter speed for freezing moving subjects and a slow (or long) shutter speed for situations where you want to blur movement for long exposures.
Slow Shutter Speed - eg. 1/10th second, or 1” (one whole second)
Fast Shutter Speed – eg. shutter speed 1/1000th second
Tip: Want to practice using different shutter speeds?
Aperture (also known as F Stop or F Number) is the size of the opening inside the camera’s lens when you take a picture. The aperture controls how much of your image is in focus (also known as the depth of field).
It’s worth nothing - The aperture is completely dependent on the lens you use (rather than the camera), and not all lenses have the same aperture range.
The aperture scale goes from F1.0 to F32, however very few lenses will offer the entire scale. Aperture is important to consider when buying a lens, as different lenses have different aperture ranges.
Which aperture should I use?
Typically a small F number is used when you want a small amount of the image in focus (small/shallow depth of field).
A large F number is used when you want a large amount of the image in focus (large/deep depth of field).
Below are two examples:
Small Aperture – eg. F/2.8
Most often used for:
Large Aperture – eg. F/16
Most often used for:
Tip: Want to practice using different apertures?
Example 1 – Running horse
Aperture: Small F number of F/5.6 so the horse stands out from the background
Shutter speed: Very fast 1/2000th Second to freeze the movement of the horse and the water droplets
ISO: Due to the fast shutter speed, this meant we had limited light entering the camera, so to help up get a correct exposure, we increased the ISO to 800.
Example 2 – Landscape with Waterfalls
Aperture: Large F number of F/16 so that everything in the frame is in focus
Shutter speed: Slow shutter speed of 1” (one whole second) – this is needed for a long exposure, to give the water a blurred/smooth effect (rather than freezing the movement)
ISO: Low ISO of 100 – as there was a long shutter speed meaning a lot of light would be coming in to the sensor, the ISO is lowered to keep the image as clean and noise free as possible
To control aperture, shutter speed and ISO individually you can shoot in manual mode.
If you’d prefer to only have to control either aperture or shutter speed, you can shoot in either aperture or shutter speed priority modes. You can then still adjust your ISO in either of these modes, or simply set ISO to Auto.
As with everything else in photography, it’s really about what works best for you.
Now that you know what aperture, ISO and shutter speed are, get out there and experiment! Try new subjects, new gear and new conditions. Make mistakes, and make something amazing! At CameraPro, we’re right behind you every step of the way.