For the first half of the 20th century, photographers had to gauge exposures without a light meter. It was common at the time for film packets to have a set of exposure guidelines printed inside them to help photographers obtain correctly exposed pictures under a range of typical lighting conditions. Many photographers still use these guidelines, especially for tricky lighting conditions, when difficult-to-meter subjects like large areas of snow or wedding groups containing white dresses and black suits can produce incorrect exposure readings.





