Digital cameras automatically give each photo a unique filename, usually consisting of a series of letters and then a number. There is one key option to be aware of – you can have the camera start renumbering from scratch each time you erase/format the memory card, or you can have it continue from the last number. This second option is the one to choose because it means that you won’t get duplicate filenames later on your computer.

Depth of field preview

Usually you view the scene with the camera lens wide open and it only stops down to your chosen aperture the moment you press the shutter button, so it’s hard to judge just how much depth of field the final photo will have. The depth of field preview stops the lens down to the taking aperture, though, so you can judge the effect in the viewfinder or on the LCD display.

Custom settings

Most advanced cameras offer a custom settings menu for changing the behaviour of the camera’s controls to better suit the way you like to work. For example, you might want to change the direction of the control dials, or the order in which bracketed exposures are taken.

Control dial

A wheel on the camera body which you turn with a finger or your thumb to change one of the camera settings. The control wheel’s function will depend on the mode or function you’ve selected. More advanced cameras have two control wheels for quicker adjustments.

Colour temperature

A traditional technical measurement for the white balance setting that uses temperature values in degrees Kelvin rather than named presets like ‘Direct Sunlight’, ‘Cloudy’ and so on. Colour temperature is used for choosing and controlling the colour of photographic lighting equipment and you can use it an alternative to white balance presets on more advanced cameras.


This is short-term internal memory used by the camera to store image data captured by the sensor while it’s waiting to be processed and saved to the memory card. It becomes important in the camera’s continuous shooting mode because the camera can capture photos faster than it can save them, so before long this buffer fills up. The larger the buffer, the longer you can keep shooting.