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This list covers optical lens designs grouped by tasks or overall type. The field of optical lens designing has many variables including the function the lens or group of lenses have to perform, the limits of optical glass because of the index of refraction and dispersion properties, and design constraints including realistic lens element center and edge thicknesses, minimum and maximum air ...
Diagram of Petzval's 1841 portrait lens - crown glass shaded pink, flint glass shaded blue. The lenses of the very earliest cameras were simple meniscus or simple bi convex lenses. It was not until 1840 that Chevalier in France introduced the achromatic lens formed by cementing a crown glass bi-convex lens to a flint glass plano-concave lens.
Lenses used in portrait photography are classically fast, medium telephoto lenses, though any lens may be used, depending on artistic purposes. See Canon EF Portrait Lenses for Canon lenses in this style; other manufacturers feature similar ranges. The first dedicated portrait lens was the Petzval lens developed in 1840 by Joseph Petzval.
The most famous example is the Rapid Rectilinear Lens developed by John Henry Dallmeyer in 1866. It allowed distortionless photos to be taken quickly for the first time, and was a standard lens design for 60 years. [1]: 59 As of 2020, the Laowa 9mm f/5.6 lens is the world's widest rectilinear lens for full frame cameras.
If the right lens is inserted, so that the chosen distance roughly equals the distance of the drawing surface, both images can be viewed in good focus simultaneously. [ citation needed ] If white paper is used with the camera lucida , the superimposition of the paper with the scene tends to wash out the scene, making it difficult to view.
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A line drawing is the most direct means of expression. This type of drawing without shading or lightness, is usually the first to be attempted by an artist.It may be somewhat limited in effect, yet it conveys dimension, movement, structure and mood; it can also suggest texture to some extent.