Īs the aperture is adjusted, the opening expands and contracts in increments called f-stops. The size of the aperture can be set manually, by rotating the lens or adjusting a dial or automatically based on readings from an internal light meter. Typically located in the lens, this opening can be widened or narrowed to alter the amount of light that strikes the film or sensor. Light enters the camera through an aperture, an opening adjusted by overlapping plates called the aperture ring. The first permanent photograph was made in 1825 by Joseph Nicéphore Niépce. The modern photographic camera evolved from the camera obscura. The word camera comes from camera obscura, which is Latin for 'dark chamber' and refers to the original device used to project a 2D image onto a flat surface.

Similar artistic fields in the moving-image camera domain include film, videography, and cinematography. Captured images may be reproduced later through processes such as digital imaging or photographic printing. The still-image camera is a key instrument in the art of photography. Cameras have various mechanisms to control how light falls onto the light-sensitive surface, including lenses that focus the light and a shutter that determines the amount of time the photosensitive surface is exposed to the light. At a basic level, most cameras consist of a sealed box (the camera body), with a small hole (the aperture) that allows light to pass through and capture an image on a light-sensitive surface (usually a digital sensor or photographic film). Most cameras can capture 2D images, while some more advanced models can capture 3D images. A camera is an optical instrument that captures images.

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