Photography Terminology
Aperture
Light passes through an opening in your lens before reaching the camera sensor (or film). This opening is referred to as the “aperture” and is measured in “f-stops” (see below).
If you relate the process of capturing light to the human eye, the aperture would be your pupil.
Bokeh
“Bokeh” derives from a Japanese word and refers to the quality of the background “blur” in an image. Often used in portraiture – the subject kept in sharp focus, the background rendered with a soft blur in order not to distract from the subject. A few variables involved in achieving this effect, but the common starting point is a wide-open aperture, which results in a shallower depth of field.
Burst mode
Also known as “continuous shooting mode” – several images taken in quick succession by holding down the shutter button (or by pressing it once on some models). Often used in sport or wildlife photography, where timing a single image can be challenging.
Composition
Refers to how images within a photograph are positioned in relation to each other – the “rule of thirds” is probably the best known guideline in this respect.
Depth of Field
This relates to the area of an image that is in sharp focus, i.e. the distance between the nearest and farthest elements in a photograph that are in focus. This “depth” will mainly depend on the aperture chosen and the distance from camera to subject.
Digital Zoom
Your camera and lens will give you a natural “optical zoom”, but in some cases you may want more and, if your camera has the option, you may opt to try “digital zoom”. Here, the processor in the camera tries to enhance what can be seen through normal “optical” functionality. Optical is better than digital as you’re seeing the real thing, rather than artificial enhancement.
Exposure
This is the amount of light that reaches your camera sensor, which affects how bright or dark your image will be. It is influenced by aperture, shutter speed and ISO – the three components of the exposure triangle.
To understand this in more depth, I would recommend Understanding Exposure, Fourth Edition: How to Shoot Great Photographs with Any Camera
Exposure Compensation
Exposure Compensation is used to alter the settings chosen by in-camera software when it determines the “correct” exposure for an image using the camera’s in-built light meter. Use this to deliberately under or over expose an image. Think of this as a way of overwriting exposure values chosen by your camera.
Exposure Triangle
An important element of understanding how exposure is affected by the relationship between aperture, shutter speed and ISO. I would highly recommend this video by Sean Tucker.
F-stops
OK, I’ve taken this from Wikipedia to give you an idea of how complex this can be to fully understand…” The f-number of an optical system is the ratio of the system's focal length to the diameter of the entrance pupil. It is a dimensionless number that is a quantitative measure of lens speed, and an important concept in photography. It is also known as the focal ratio, f-ratio, or f-stop”.
However, fear not – just think of an “f-stop” as a measure of your aperture size, i.e. how big is the hole through which light passes before reaching your sensor. A low number, such as f1.8, gives a larger aperture (hole) than a large f-number, such as f-16.
Admittedly this can be confusing, but that’s the way it is – don’t fight it. It’s an important concept to understand. Aperture = hole size. Small number = big hole. Large number = small hole.
OK, enough about holes, time to move on.
File Format
The most common and recognisable format is “JPEG”, “Joint Photographic Experts Group”. You will see different RAW formats used by different camera manufacturers – these RAW files will be developed and converted into JPEG files for ease of use and sharing. For example, .CR2 is a RAW format used by Canon, .ARW is a Sony format and Leica go with .DNG
Focal length
Apologies, this can be another complicated explanation for what is a relatively simple concept. The focal length of a lens refers to the distance between the camera sensor and the lens when an image is in focus. This distance is usually referred to in millimetres (mm)
What is important to know is that small numbers, such as 24mm, equate to “wide angle” and large numbers, such as 200mm, get you closer to a subject. So for landscapes you usually want a fairly wide angle, but for wildlife, you would prefer a longer focal length – as high as 400mm or more.
Focus
The two main methods to think about are “autofocus” and “manual focus”. When using the autofocus mode, the camera will determine the focus point based upon your camera settings – you should be able to move the focus point as required, using standard camera functionality. You choose the point, the camera does the rest. For manual focus you do this work yourself – you may want to use this, especially a method called “zone focusing”, in situations where potential subjects are moving. Street photography would be an example.
Hot Shoe
Easy one, this – the slot on top of some cameras (those without in built flashes) where you slot in a flash unit.
ISO
To all intents and purposes, ISO measures the sensitivity of your sensor to light. Or film sensitivity back in the day.
Purists may dispute this with regards to sensors and give a more complex answer. For our purposes, we don’t need to know all that – but please do investigate it more if you feel the need.
Whereas the sensitivity of a film was fixed for the whole roll, digital sensor sensitivity can be adjusted shot-by-shot. The higher the ISO number, the higher the sensitivity to light. We get back to the exposure triangle here, please do watch that video. Basically, a higher ISO would allow a faster shutter speed and/or a smaller aperture. Understanding the ISO/aperture/shutter speed relationship is important. Watch the video.
ISO numbers tend to range from ISO 100 upwards (e.g. ISO 6400 and beyond), with the upper range getting ever higher as technology improves. A potential downside to be aware of is that high ISOs can result in “digital noise”. In the film days, this was known as grain – and can actually look good in some black and white images.
Manual mode
You take control of the camera settings – you manually select the aperture, shutter speed and ISO. I’d probably forgive you for using “auto ISO” if your camera has that option – i.e. the camera chooses the ISO based on available light and your chosen aperture/shutter speed.
Noise
Known as “grain” back in the film days. In the digital world, noise can be a side effect of using a high ISO
RAW
A RAW file is one that has not undergone any processing, it is a file displaying an image exactly as captured by the camera. To produce a jpeg, a RAW file must be converted. When editing, it is better to do so on a RAW file as there will be more detail or information to work with.
An analogy – imagine a raw piece of beef (sorry vegetarians). You could make all sorts of beef-related meals – Bolognese, steak, various pies – wherever your fancy took you and whatever your skillset could produce. However, if someone else did the prep and gave you a ready cooked steak – well, job’s done and your option to make something else are limited.
There you go, there’s a RAW/jpeg analogy that kinda works.
Rule of Thirds
A compositional guideline that can make images visually more appealing to the human eye. In short, key elements of an image are placed at specific points such as a third along…a third down etc. Many cameras can show these gridlines in viewfinders or live view screens. However, it is a simple concept that you should pick up quickly.
Shutter speed
A measure of how quickly/slowly your shutter opens to allow light to pass and reach your sensor. To use your eye as a comparison again, it’s like blinking. A slow shutter speed lets in more light – think of waterfall images where the water is smooth. That’s a slow shutter speed, that is. However, be wary of camera shake – use a tripod.
Sunny 16 rule
Also known as the “sunny f16 rule”. This is a useful guideline to obtaining a “proper” exposure on a bright, sunny day – and can be used as a baseline from which to adjust expose based on the light conditions.
On a sunny day, set your aperture to f/16 and your shutter speed to 1/ISO value – so, ISO 200 = shutter speed 1/200. Then take your shot – your exposure should be pretty damned decent.
If the daylight isn’t optimal, tweak the settings – but “sunny 16” is useful to know.
White Balance
You’ve probably seen this setting on your camera and possibly just left it on auto – effectively letting the camera decide the WB for you. That’s perfectly fine and the WB is a setting that can be adjusted in the editing phase anyway, if you shoot in RAW. But ideally you should understand what it is.
White balance is the process of removing unrealistic colour casts in an image, ensuring objects which appear white in person are rendered white in your photo
In simple terms, different light sources produce different temperatures of light and can result in colour casts on your images. Controlling your white balance negates this effect. That’s pretty much what you need to know.
To think a little more about it, the same object viewed under different light sources will appear differently – fluorescent light, moonlight, tungsten – all produces different light temperatures – measured on the Kelvin scale. You get warm lights and cool lights.
This image had an exposure time of 6 seconds, to help with smoothing the water. It is also an example of a “wide angle” shot - the focal length was 17mm.