Photography triplet
A photography or paint triplet is set of three photos or paints usually related to one event or developing a theme or story. Many art photographers use triplets to describe more complicated story or to attract the viewer by showing related prints together. It is different from a Triptych, which is a work of art divided into three sections.
Some art critics like triplets because the best photographers are able to describe as complicated story as in simple documentary movie. Some triplets are the same image repeated with slight alterations or, more rarely, seemingly identical images with minor, detailed changes.
Triplets are usually framed together or, in galleries, mounted near each other on the wall. Triplets are very often used on postcards.
When four photos or paints are together, it is called photography quadruplet. Multiple images chained together are called photography fold.