Because each of the three A900 images above is 2016 pixels wide, this means
that, if printed at 150 pixels per inch, each print would be 13.44
inches wide. Therefore, if the full A900 image width of 6048 pixels is
printed at 150 pixels per inch, the print will be 40.32 inches wide.
Some of the printers used by photographers have a maximum print
width of say, 19 inches. Therefore, by making three equal-sized prints, the
photographer can produce a triptych which has the equivalent print width of
a single print that is about, say, 40 inches wide, without the need to use a
much larger printer.
If the three images are mounted on photo blocks that are thick enough to
stand on their own, the two outer blocks can be turned inwards slightly to
give a semi-circular impression of the image that appears to provide more
Of course, you can, if you prefer, split the image into two panels and make a
diptych rather than a triptych!
to see further discussion about the image above.
The triptych has been around for a long time as an accepted work of art, as
The above article says that the "triptych form arises from early Christian
art, and was a popular standard format for altar paintings from the Middle
A triptych can take the form of one picture split into three parts, as shown
above, or it can be three separate compatible pictures displayed together,
as shown in this article about the triptychs of Francis Bacon: