Photography is an old technology, and in the nearly two centuries since its discovery a dictionary’s worth of terminology has sprung around it.
For beginner photographers, this can mean that even picking up a how to guide can be an exercise in frustration. Imagine trying to follow a recipe for hummus not knowing what a chickpea was – that’s the position many beginner photographers find themselves in.
To help you take your first step towards mastering your camera and your new hobby, digiDIRECT has put together definitions for the ten essential terms you need to learn to get started in photography.
Image sensor
First, learn a little bit about your camera itself. Your image sensor is arguably the most important component in your kit. Functioning as a digital equivalent to the photographic film used in an analogue camera, an image sensor converts light into electronic signals that become the image you see on your screen.
A range of different technologies exist for image sensors, but even entry-level models like the Canon EOS 100D use active pixel sensors in complementary metal–oxide–semiconductor (CMOS) – the same type used in top-of-the-line full-frame DSLR cameras.
Exposure
In general terms, exposure is the amount of light that hits your digital camera’s image sensor. This is controlled by a number of factors, some of which you can control like (aperture, ISO and shutter speed) and some which you can’t (environmental factors).
Exposure can be further manipulated to achieve specific niche effects. A frequently seen example is the use of long exposures – allowing light to hit the image sensor for an extended period of time. This can be used to either illuminate stationary objects in a low-light environment (such as when taking a photo of stars in the night sky) or to give the impression of movement (transforming cars in motion on a road into streaks of light).
Aperture
In general terms, an aperture is an opening or gap in something. When used in the context of photography, it refers to both the diameter of an opening that artificially limits the amount of light that hits the lens as well as the mechanism that allows the user to change this diameter. This mechanism opens and closes, resembling a pupil dilating and constricting in response to changing light conditions.
Different diameters of aperture are specified using an f-number or f-stop. The side of your lens will have a series of numbers along the side notated with ‘f/’, generally running from below 5 (as in ‘f/4’) to above 20 (‘f/22’). The higher the number, the smaller the aperture and the less light is let onto the image sensor. Aperture size will greatly depend on available lighting.
Film speed/ISO number
Where the aperture controls how much light reaches the image sensor, film speed determines the sensitivity of the sensor itself to light. Different sensitivities are referred to as differing ISO numbers, with higher numbers denoting greater sensitivity.
Setting the film speed too high will result in noise (described below) on an image, so the challenge is always to use the lowest film speed possible for each and every shot to minimise the chance of noise.
Shutter speed
Remember when we talked about long exposure photography? This is what makes that happen. Your camera’s image sensor is not constantly exposed. To take a photograph, it only needs to be exposed for a fraction of a second – most commonly 1⁄500 or ?1⁄250 of a second.
This also controls how much light hits the image sensor, with longer exposures equalling greater light. Using too fast a shutter speed can lead to images being too dark.
Photographing fast-moving objects will require a faster shutter-speed – runners and athletes are often photographed at ?1⁄4000, while static landscape shots can be taken at ?1⁄125 and below.
White Balance
The white (or colour) balance is a setting that allows the user to compensate for different colour lighting in different coloured situations.
An object photographed under orange incandescent bulbs will look drastically different when photographed outside on a clear day. White balance allows you to compensate for this variation in ambient lighting, ensuring that a wedding dress looks the same as the ceremony moves from inside the church to an outdoor reception.
Focus
An object in focus appears clear and sharp with visible details, while an object out of focus appears blurry and indistinct. Depending on your camera, you may have a choice of manually focusing your images, or relying on a computer-controlled autofocus that – in some cameras – can accurately track moving objects between shots.
Either way, it’s good practice to familiarise yourself with manually setting focus. Not only will it help you produce a wider variety of shots, it’ll give you a greater understanding of how your camera works.
Depth of field
Depth of field (DOF) refers to the point at which an object appears sharp and clear in a photograph, beyond which the image appears blurry. A larger aperture will give a narrower DOF, while a smaller one will result in a larger DOF. Described in metres, it can range from fractions of a millimetre (in the case of macro photography of very small objects) to infinite (wherein an entire landscape or mountain range would be in focus).
DOF is an artistic as well as a practical choice. For example, a narrow DOF emphasises the subject of the photograph while de-emphasising everything around it, focusing the viewer’s attention more sharply.
Noise
Noise refers to variations in colour or brightness in images that do not appear in the subject itself. These variations occur for a variety of reasons, but most result from improper setting of film speed or shutter speed – too high and images will appear grainy.
Additionally, smaller image sensors are more susceptible to noise. Cameras equipped with larger sensors can take photographs at much higher film speeds without producing detectable noise. If you plan to do a lot of high-speed photography, factor this into your purchasing decision.
Image processing
A lot happens between you pushing the shutter release button and viewing an image on the camera’s LCD screen. Between the image sensor capturing the light and you being able to see the photo you’ve taken, most cameras by default will perform a series of functions on the image such as reducing noise, scaling the image, correcting colour and encoding it into a file that your computer can read, such as a JPEG. This is referred to as an image pipeline.
For beginner photographers, then image pipeline should not be tampered with and the above series of functions will improve the quality of the photo. As you gain experience and confidence, you may want to deactivate the image pipeline, forcing the camera to output what’s referred to as a raw image. While most image viewing software cannot read these photographs, they offer experienced photographers more options in how they edit their photographs.
We hope this guide has helped you understand your camera a bit more. If you’re looking to upgrade your kit, digiDIRECT offers a full range of camera bodies and lenses for the beginner photographer, helping you get started the right way.
