Entertainment / Photography / Petzval Lens
Petzval Lens: Early lens system developed by joseph petzval. It had a very wide aperture and was relatively free from aberration. Many modern lenses have developed from this simple three-element design.
Positive Lens: Simple lens that causes light rays from a subject to converge to a point.
Portrait Lens: Lenses produced specifically for portraiture. They usually have a long focal length and produce a slightly diffused image.
Process Lens: Lens system designed specifically for high quality copying.
Single Lens Reflex (SLR): Stands for single lens reflex. It is a camera of 35mm or medium format in which a system of mirrors shows the user the image precisely as the lens renders it.
Slow Lens: Lens with a small maximum aperture, such as f/8.
Single-Lens Reflex (SLR): An SLR, or single-lens reflex, camera is named for its picture-taking mechanism. In a film SLR, the viewfinder uses a 45°-angled mirror to see through the lens; that mirror snaps out of sigh . . . View Full Definition
Reflex Lens: Alternative term for mirror lens.
Normal Lens: A type of focal length that seems to most closely approximate the human eye's range of vision (in actuality the range of vision is narrower in a normal focal length lens, with less illusion . . . View Full Definition
Macro Lens: Is a lens specially designed to give accurate resolution of a very near subject without the need for supplementary attachments. Sometimes, incorrectly, referred to as a micro lens.
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