In modern printing, a proof is a test print to show exactly what the final print will look like. Typically it is run on an inkjet copier. It is good for catching typos and some rendering distortions like font issues. However, it isn't a good way to predict true colour in the printing process as it is not an exact proof. In art, proofs or trial proofs have the same function: to make sure the art is reproducing as planned. Proofs are done before a final run of a print is done to allow the artist to change and improve the image.
In art production when the trial proof is approved the edition is run. The approved print is the printer's proof and is kept by the printer. It is marker "P.P." Traditionally, the publisher or artist gave the printer extra copies as an acknowledgement of a job well done. Today the number of printers' proofs is about the number reserved for the artist. The artist's proof refers to the percentage of the prints of a series that is run off and kept by the artist. It is usually about 10 per cent of the prints and they are marked "A.P." Both of these runs are typically identical in appearance to the limited edition, but may vary by the colour of ink and type of paper used.
The artist's and the printer's proof can be used by the artist and printer for their own personal use or can be sold or given away. They are considered an investment, allowing the printer to share in the benefits of his skill.
For collectors the question "Are printer's proofs more valuable?" comes up a lot. Most art prints are numbered, but not all printer's proofs and artist's proofs are. Since the printer's and artist's proofs are almost identical to the limited edition and run at the same time, they usually are no more or less valuable. All prints are signed by the artist.
An edition is the number of prints run in a series. These are signed by the artist and numbered--1/100, for example. The printer's proof and artist's proof are not counted in the limited editions. This practice can give buyers a skewed idea about the rarity of a particular print. There may be 120 total prints instead of 100.
Types of Art Prints
Giclee, silk screen and lithography are common types of art prints that are considered original art that is typically run in editions, numbered and signed by the artist.
A printer's proof in art photography is the master proof against which all other prints are compared to check for quality and colour. Photography prints are not always run at the same time. The photographer himself may create the master proof.