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shutter

On this website, the term “shutter” refers to whatever means is used to determine when a camera’s capture surface begins recording light and when it stops doing so.

This action could be mechanically, electronically, or primitively controlled (for view-camera users making a long exposure with a lens-in-barrel or pinhole arrangement, the “shutter” could be something as simple as a hat, a piece of cloth, or a lens cap).