An introduction to camera modes, and how to start moving away from using full automatic
If you have a dedicated camera such as a bridge, DSLR or mirrorless (as opposed to just a phone camera) you are very likely to have a mode dial similar to the ones shown in the illustration above; but do you know what they mean, what they do and how to use them?
First we need to understand what a camera is doing when you press the shutter. The amount of light that goes into making a photo (the 'exposure') depends on three key elements:
1. The size of the APERTURE (how wide open the lens goes)
2. The SHUTTER SPEED (how long the aperture in the lens remains open)
3. The SENSITIVITY of the sensor to light (called ISO)
As well as controlling the amount of light that goes into making the picture, each of these factors also dictate the key creative aspects of photography; we will look at the two main ones:
1. The size of the APERTURE also dictates the DEPTH OF FIELD in the photo, or the amount of the photo that is in focus; a large aperture causes a shallow depth of field (think of a portrait photo with a blurred background - that is a shallow depth of field). A small aperture causes a deep depth of field (think of a landscape photo where everything from near to the camera to far away is in focus; that's a deep depth of field).
2. The SHUTTER SPEED will dictate whether any motion is FROZEN (fast shutter speed) or BLURRED (slow shutter speed).
So, now let's go back to the mode dial and look at what your camera is doing on just a handful of the key modes:
Auto Mode ('AUTO')
In this mode, your camera does everything for you; it will try and identify what scene you are looking at and therefore what settings to use. For example, if you point it at a person it will often show a small head and shoulders icon (to show it's identified a person) and will therefore use a fairly fast shutter speed to prevent any blur if the person moves. It will also assume that you want to blur the background and will therefore choose a fairly large aperture. If it detects a landscape (it is likely to show an icon of some mountains) it will assume you want a deep depth of field by selecting a smaller aperture. The camera will also use a light meter to measure the amount of ambient light, and set all of the other key settings to ensure a well exposed photo. Auto Mode may well be fine in many situations, but what if you want to do something different, such as a landscape with a shallow depth of field, or intentionally blur motion with a slow shutter speed? Well, this is where the other modes come in.
Aperture Priority (Normally 'A')
This gives you full control of the aperture, and therefore also control over the depth of field (the amount of the photo in focus). In this mode, you are able to change the aperture, and the camera will then set the other settings to ensure you get a well exposed photo. So, if you want to take a photo of a person, but you want a wide depth of field so that what is behind them is also in focus? Then you can use this mode to force the camera to take the photo using a small aperture.
Shutter Priority (normally 'S')
This mode gives you full control over the shutter speed, and therefore over whether you freeze motion or blur motion. So, instead of taking a photo of a wave in Auto Mode which would decide to freeze the motion of a wave, you instead wanted to slightly blur the wave motion; you could use shutter priority to select an appropriate shutter speed, and the camera would then take control of the other key settings to ensure a well exposed photo.
Manual Mode ('M')
This is the mode which is most complicated to use, but provides full creative control of your camera. It allows you to set the Aperture, Shutter Speed and ISO all independently, so that you can have full control over the creative aspects of the photo including motion freeze / blur and depth of field. In this mode however, the camera does nothing for you, so does not balancing the amount of light to ensure a well exposed images: So if you get these settings wrong, you can easily underexpose and end up with a completely black photo or overexpose and end up with a completely white one!
Getting off Auto is the key to unlocking your creativity!
As getting off AUTO mode is critical to being able to unlock the creative potential of you and your camera, this is what I focus on teaching in all of my beginners photography courses. It can seem complicated at first, however I've been told I do a good job of making it as simple as possible and have never had a student walk away from one of my courses without being able to understand the basics of shooting on Manual! You can see all of the 1-2-1 courses I currently offer here and residential group workshops here.