essential skills: digital photography in available light
Format
Format refers to the size and shape of an image. A certain amount of confusion can surround this
term. It applies to both ‘camera format’ and ‘image format’. An image can be taken or cropped
in the vertical or horizontal format using different format image sensors.
A vertical image (one that is tall and narrow) is described as ‘portrait format’ even if the image
is a natural landscape. A horizontal image is described as ‘landscape format’ even if the subject
is a portrait. The origins of this terminology date back to when traditional artists were a little more
conservative with their intended use of the frame.
In editorial work photographers must ensure that images are taken using both vertical and horizontal
formats. This gives the graphic artists the fl exibility to design creative pages.
Most prosumer digicams and DSLRs currently available use sensors that have a 4:3 format or
‘aspect ratio’. The aspect ratio is a numerical way of describing the shape of the frame. A 4:3
aspect ratio means that for every unit of height, the width is one and a third times wider. 4:3 is a
numerical description of this ratio without using fractions. This format is the same as a standard
computer screen, e.g. 1024 x 769 pixels. DSLRs that use full frame sensors such as the Canon
5D have an image sensor with a 3:2 aspect ratio that matches 35mm fi lm (36mm x 24mm). This
is a slightly wider format but not as wide as a wide-screen television that has a 16:9 aspect ratio.
Some prosumer digicams now offer 3:2 as an alternative aspect ratio whilst cameras such as
the Panasonic LX-1 and Leica D-LUX 2 use a CCD image sensor with a 16:9 format. The aspect
ratio of a single page in this book is close to 4:3 whilst a double-page spread from this book is
closer to the 3:2 aspect ratio. Care needs to be taken when framing images for editorial work. The
photographer has to be prepared to lose some of the visible image in the viewfi nder if an editor
wants to produce either a full-page or double page image spread from an image captured in a
different aspect ratio. Many photographers instinctively design full frame. This can later create
diffi culties when trying to crop the image to a different format.