Learn & Understand

The Frame and the Mat: Protecting and Presenting Art

The border of mat board around a photograph does two things at once: it protects the art and it presents it. Both the frame and the mat descend from a long tradition of setting precious images apart — and the small trick of a slightly deeper bottom margin is a nod to how the eye actually reads a framed picture.

The Frame as a Boundary

A frame draws a hard line between the artwork and the wall, declaring the image a distinct object worthy of attention. Historically, frames were architectural and elaborate — carved and gilded surrounds that echoed altarpieces and windows — asserting the value of what they enclosed. The frame's oldest job is to say: what is inside this boundary is meant to be looked at.

Why a Mat Exists

The mat — the border of board between art and frame — is partly conservation and partly composition. Physically, it holds the artwork away from the glass, preventing the image from sticking to or being damaged by contact with the glazing as humidity changes. Compositionally, it gives the eye a quiet margin, a breathing space that separates a busy image from the frame and the wall beyond.

The Weight of the Bottom Margin

Professional framers often cut the bottom border slightly deeper than the other three. The reason is perceptual: with mathematically equal borders, the eye tends to read the image as sitting a touch too low, as if sinking in its frame. A marginally wider bottom counterweights this illusion, making the artwork appear optically centered — a correction, not a mistake.

Conservation Materials

Serious framing uses acid-free, archival mat board, because ordinary board can, over years, release acids that yellow and eat into paper — the brown burn line sometimes seen on old prints. Choosing conservation-grade materials is what lets a frame protect an image for generations rather than slowly damaging it, turning presentation and preservation into the same act.

Sizing the Mat

To calculate a mat's overall dimensions from artwork size and border width, use the Picture Frame Mat Calculator. Arrange the finished frames evenly with the Wall Art Spacing Calculator, and coordinate them with the room via the Room Color Scheme Calculator.