These lens attachments include polarizing star & neutral density
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A Guide to Filters for Lenses | explora - B&H  If you ask most consumer-camera owners why they keep a filter on their lens, a majority will most .... Though they look and perform identically, circular Polarizing filters are designed ... What are Neutral Density filters and how would I use them? ... Examples of these types of scenarios include landscapes in which the top of a...
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J! Archive - Show #2911, aired 1997-04-07  It includes the lines "What a glorious feeling, I'm happy again, I'm laughing at clouds..." .... These lens attachments include polarizing star & neutral density...
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Lens Filters Explained - Photography Life  Sep 8, 2011 ... Star filters make bright objects look star-like; softening/diffusion filters create a dreamy look ... Because it is impractical for graduated neutral density filters to be circular (due to ... In the past, these filters were used to block UV from hitting the film. ... Avoid using a polarizing filter on ultra wide-angle lenses.
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Photographic filter - Wikipedia  Exceptions include the ultraviolet (UV) filter typically used to protect the front surface of the lens, the neutral density (ND) filter, the polarising filter and the infra...
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Television Production: Lens Filters and Lens Attachments  Jan 10, 2016 ... You're probably familiar with polarizing sunglasses that reduce reflections and cut down glare. Unlike sunglasses, however, the effect of most...
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Fresnel lens - Wikipedia  A Fresnel lens is a type of compact lens originally developed by French physicist .... One such lens was on hand when it was decided to build and outfit the ... These lenses have application in solar power, such as focusing sunlight on a solar panel. ... Linear: A non-imaging linear Fresnel lens uses straight segments whose...
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Telescope Types - Fort Worth Astronomical Society  Apr 3, 2014 ... A lens at one end of a tube, with the eyepiece and focuser at the other end, on a ... It uses a convex glass lens (to bend light and bring it into focus. ... These defects reduce the overall light gathering ability of the lens by blocking ... Newton built his reflecting telescope because he suspected that it could prove...
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Which Lens is Best for You - X-Cel Optical Company  There are several specialized lens styles that will make on-the-job vision more ... There are several progressive-type "mid-distance, variable focus" lenses that offer a ... Lens Selections: Ribbon or Bar multifocal segments when distance acuity is ... Critical Factors: Focal length (near, intermediate and distance) to the viewing...
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Patent US20100040196 - X-ray generator for achieving ... - Google  Feb 18, 2010 ... An X-ray generator (101) for achieving stereoscopic imaging effect and an X-ray .... There is a kind of bifocal tube, the kind of bifocal tube has two groups .... The stereo image pair is gained by stereo vidicon of double lens.
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Contact Lenses | American Keratoconus Association  Soft Lenses  by far these are the most popular type of contacts worn by a ... Toric lenses which correct for astigmatism can provide good vision for lower ... Rigid Gas-Permeable (RGP)  these are contacts that are harder than soft lenses.
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Which Prescriptions Go With Which Lenses? | Through the Lens  Feb 21, 2014 ... We can fill these for single-vision (not multifocal) prescriptions up to 5.00 in ... The type of multifocal eyeglasses known as progressives are glasses with no visible line between the three different focal segments, which are distance ... the top of the lens, intermediate (computer) vision at the middle of the lens,...
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The best Full Frame lenses for the Sony E-mount system (October ...  Jan 13, 2016 ... Besides native FE lenses, E-mount cameras are compatible with a wide array ... Like most of Zeiss' wide angle primes, the Batis 18mm lens uses a Distagon ... For some people, wide angle lenses go up to 35mm inclusive, with 50mm ... The Sony Zeiss FE 50mm f/1.4 Planar T* definitely embraces this need.
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Golden Era of Refractors (Cosmology: Tools)  The trick was to combine a concave lens made from a leaded ("flint") glass ... One of these was a 9.5-inch telescope at Russia's Dorpat Observatory, installed in 1824 by F.G. Wilhelm Struve. ... Alvan Clark died at the age of 83 in 1887, the same year that the Lick 36-inch refractor was dedicated. ... 40" telescope at Yerkes...
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Glossary - IBEX: Interstellar Boundary Explorer - Southwest ...  Dark cloud: An interstellar cloud of gas and dust that contains enough dust to ... Disk: The visible surface of the Sun (or any heavenly body) projected against the sky. ... the solar limb, Filaments seen over the limb are also known as prominences. ..... Parts of the solar atmosphere include the photosphere, chromosphere, and...
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Camera Glossary - Basic Terminology of Digital Photography  Jun 11, 2014 ... A large aperture allows in both light rays directed straight at the lens ... CCD  Short for charged coupled device, a CCD is a sensor type ... Contrast detection autofocus  This AF technology uses light sensors behind the lens, ..... this is a mechanical curtain that opens and closes to expose the image sensor...
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Converter Lenses: Overview  If a 0.8X wide angle converter is used, the combined focal length is in the ... These include lens flare, ghost image, field curvature, aberration and so on. ... The available converter lenses have three types: fisheye, wide angle and telephoto.
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Patent US7233354 - Digital camera that adjusts resolution for low ...  Jun 19, 2007 ... a lens for directing light into said digital camera; .... been adjusted by varying the typical mechanical exposure settings of shutter speed, .... The shutter 20 is mounted in the imaging light path 11 b behind the lens assembly 12 and aperture 18 and is a normally closed device that snaps open to let light pass...
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Stereofluoroscopic apparatus - Patent 0063252  Oct 27, 1982 ... The apparatus further has a lenticular lens sheet (136-1) on a flat ... [0002] Conventional methods for stereoscopic observation of a fluoroscopic X-ray image-include a ... and a bifocal point X-ray tube 6 which radiates X-rays from two focal ... The X-ray image intensifier tube 8 converts the received X-ray...
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Modern Contact Lens Materials: A Clinical Performance Update  Sep 1, 2002 ... High-water content soft lenses need to be made thicker than their low-water ... All contact lens materials are polymers, which are either ... material (poly-2-hydroxyethyl methacrylate or polyHEMA) developed by Otto ... One approach to achieve this goal incorporates of two "phases" into the materials.
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optics - Is a quartz lens necessary to prevent UV blocking on full ...  May 18, 2015 ... It's true that most lenses don't transmit very much UV light, however, it's not true ... I am not sure what the spectral transmission of glass is at 250nm but you can ... Eg, you would take a camera and then use a series of different light ... that is illuminated by the UV light to make sure that the lens can not only...
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Maksutov telescope - Wikipedia  The Maksutov (also called a "Mak") is a catadioptric telescope design that combines a spherical ... Maksutov telescopes have been sold on the amateur market since the 1950s. ... the complex Schmidt corrector plate with an all-spherical "meniscus corrector ... That makes them ideal for tracking, remote viewing, and radar...