Lens hood

In photography, a lens hood or lens shade is a device used on the front end of a lens to block the Sun or other light source(s) to prevent glare and lens flare. Lens hoods may also be used to protect the lens from scratches and the elements without having to put on a lens cover.
The geometry of a lens hood is dependent on three things: the focal length of the lens, the size of the front lens element and the dimensions of the image sensor or film in the camera.

Cause of lens flare

Flare occurs when stray light strikes the front element of a lens and then bounces around within the lens. This stray light often comes from very bright light sources, such as the Sun, bright studio lights, or a bright white background. If a light source is in the lens' angle of view, a lens hood will hardly have any effect, but the light does not have to cause lens flare. It is sufficient that stray light from a bright light source enters the lens. Multi-layer coatings in newer lenses also help to reduce lens flare.

Lens

Lens may refer to:

Optics

Other radiation focus and forces

Places

Lens (surname)

Lens is a surname. Notable people with the surname include:

Lens, Switzerland

Lens is a municipality in the district of Sierre in the canton of Valais in Switzerland.

History

Lens is first mentioned in 1177 as de Lenz.

Geography

Lens has an area, as of 2009, of 13.9 square kilometers (5.4 sq mi). Of this area, 5.07 km² (1.96 sq mi) or 36.4% is used for agricultural purposes, while 5.48 km² (2.12 sq mi) or 39.4% is forested. Of the rest of the land, 2.74 km² (1.06 sq mi) or 19.7% is settled (buildings or roads), 0.1 km² (25 acres) or 0.7% is either rivers or lakes and 0.46 km² (0.18 sq mi) or 3.3% is unproductive land.

Of the built up area, housing and buildings made up 11.2% and transportation infrastructure made up 4.0%. while parks, green belts and sports fields made up 3.8%. Out of the forested land, 33.6% of the total land area is heavily forested and 5.8% is covered with orchards or small clusters of trees. Of the agricultural land, 0.4% is used for growing crops and 11.6% is pastures, while 9.1% is used for orchards or vine crops and 15.3% is used for alpine pastures. All the water in the municipality is in lakes.

Hood (band)

Hood are an English indie rock band from Leeds, formed in 1991. The band consists of brothers Chris and Richard Adams, and friends (including, at times, Craig Tattersall and Andrew Johnson of The Remote Viewer, and Nicola Hodgkinson of Empress).

History

Hood's first releases were very limited vinyl singles on various small independent record labels.

In 1994, record labels Fluff and Slumberland Records released Hood's first full length album, Cabled Linear Traction. Slumberland also released 1996's Silent '88, and the following year Happy Go Lucky Records released Structured Disasters, a compilation of tracks from singles. All featured a large number of short tracks (many of less than a minute), a mixture of indie rock, noise experiments reminiscent of Sonic Youth or Pavement, and an increasing interest in electronics.

In 1997, Domino Records signed Hood and released the single "Useless". Produced by Matt Elliott (better known as the Third Eye Foundation), it was a far more straightforward and tuneful song than any they had released so far. Elliott toured with the band, and produced the albums Rustic Houses, Forlorn Valleys and The Cycle of Days and Seasons. Like the single, these abandoned the short songs and instrumental snippets for longer pieces, with a pastoral sound similar to Bark Psychosis or Talk Talk. The band continued to release singles for other labels; "The Weight", for 555 Recordings, was a return to the older style with eight tracks on a 7" disc.

Hood (novel)

Hood is a novel written by Irish author Emma Donoghue in 1995. The book was the recipient of the 1997 Stonewall Book Award and is heavily influenced by James Joyce's Ulysses.

References

Convertible

A convertible or cabriolet is an automobile body style that can convert between an open-air mode and an enclosed one, varying in degree and means by model. Convertibles evolved from the earlier phaeton, an open vehicle without glass side windows that may have had removable panels of fabric or other material for protection from the elements.

Historically, a retractable roof consisted of an articulated frame covered with a folding textile-based fabric similar to that on an open carriage evolved into the most common form. A lesser seen detachable hardtop provided a more weatherproof and secure alternative. As technology improved a retractable hardtop which removes and stows its own rigid roof in its trunk appeared, increasingly becoming the most popular form.

A semi-convertible also known as a cabrio coach has a retractable or removable top which retains fully framed windows on its doors and side glass. A landaulet is a semi-enclosed convertible with a fully enclosed front cabin and an open rear, typically with a folding fabric top and roll-down glass all round.