light
Latitude
Image sensors are capable of recording a limited tonal range or brightness range. A subject
photographed in high contrast lighting may exceed this recordable or ‘dynamic range’. The ability
for the image sensor to accommodate a brightness range is referred to as its ‘latitude’.
Digital image sensors capturing JPEG images typically capture a brightness range of only 32:1 or
fi ve stops. It is essential for digital photographers to understand that when capturing JPEG images
with directional sunlight, shadow and highlight detail may be lost. The photographer capturing
RAW fi les has increased fl exibility to capture a broader range of tones and with careful exposure,
post-production processing and printing techniques they can extend this range dramatically.
Previsualization
Awareness of the subject brightness range and the capability of the photographic medium to
capture this range of tones, allows the photographer to previsualize or predict the outcome of
the fi nal image. When the brightness range exceeds the sensor’s capabilities the photographer
has the option to increase or decrease exposure to protect shadow or highlight detail that would
otherwise not record or switch to RAW capture when using a DSLR. These scenes are described
as ‘extreme contrast’.
SBR exceeding the latitude of the image sensor