iCE'

The Himalayas

The Himalaya Range or Himalayas for short (Sanskrit: हिमालय, IPA pronunciation: [hɪ'mɑlijə]), meaning "abode of snow" ), is a mountain range in Asia, separating the Indian subcontinent from the Tibetan Plateau. By extension, it is also the name of a massive mountain system that includes the Karakoram, the Hindu Kush, and other, lesser, ranges that extend out from the Pamir Knot.
The Himalayan mountain system is the planet's highest and home to the world's highest peaks, the Eight-thousanders, which include Mount Everest and K2. To comprehend the enormous scale of this mountain range consider that Aconcagua, in the Andes, at 6,962 m (22,841 feet), is the highest peak outside Asia, whereas the Himalayan system includes over 100 mountains exceeding 7,200 meters (23,622 feet).
The Himalayan system, which includes outlying subranges, stretches across six countries: Afghanistan, Bhutan, China, India, Nepal, and Pakistan. Some of the world's major rivers, the Indus, the Ganges, the Brahmaputra, and the Yangtze, rise in the Himalayas, and their combined drainage basin is home to some 1.3 billion people, including, most significantly, the people of Bangladesh. The Himalayas have profoundly shaped the cultures of South Asia; many Himalayan peaks are sacred in both Hinduism and Buddhism.
The main Himalaya range runs, west to east, from the Indus river valley to the Brahmaputra river valley, forming an arc 2,400 km long (1,491 miles), which varies in width from 400 km in the western Kashmir-Xinjiang region to 150 km in the eastern Tibet-Arunachal Pradesh region. The range consists of three coextensive sub-ranges, with the northern-most, and highest, known as the Great or Inner Himalayas.

edit @ 2 Feb 2009 22:06:36 by iCE'

In photography, exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value (EV) and scene luminance over a specified area

The exposure for a photograph is determined by the sensitivity of the medium used. For photographic film, sensitivity is referred to as film speed and is measured on a scale published by the International Organization for Standardization (ISO). Faster film requires less exposure and has a higher ISO rating. Exposure is a combination of the length of time and the level of illumination received by the photosensitive material. Exposure time is controlled in a camera by shutter speed and the illumination level by the lens aperture. Slower shutter speeds (exposing the medium for a longer period of time) and greater lens apertures (admitting more light) produce greater exposures.

An approximately correct exposure will be obtained on a sunny day using ISO 100 film, an aperture of f/16 and a shutter speed of 1/100th of a second. This is called the sunny 16 rule: at an aperture of f/16 on a sunny day, a suitable shutter speed will be one over the film speed (or closest equivalent).

A scene can be exposed in many ways, depending on the desired effect a photographer wishes to convey.

Reciprocity

An important principle of exposure is reciprocity. If one exposes the film or sensor for a longer period, a reciprocally smaller aperture is required to reduce the amount of light hitting the film to obtain the same exposure. For example, the photographer may prefer to make his sunny-16 shot at an aperture of f/5.6 (to obtain a shallow depth of field). As f/5.6 is 3 stops "faster" than f/16, with each stop meaning double the amount of light, a new shutter speed of (1/125)/(2·2·2) = 1/1000 is needed. Once the photographer has determined the exposure, aperture stops can be traded for halvings or doublings of speed, within limits.

The true characteristic of most photographic emulsions is not actually linear, (see sensitometry) but it is close enough over the exposure range of about one second to 1/1000th of a second. Outside of this range, it becomes necessary to increase the exposure from the calculated value to account for this characteristic of the emulsion. This characteristic is known as reciprocity failure. The film manufacturer's data sheets should be consulted to arrive at the correction required as different emulsions have different characteristics.

Digital camera image sensors can also be subject to a form of reciprocity failure.

Example Pictures By Exposure Technic

A photograph with an exposure time of 25 seconds

A photograph of a night-time sky with an exposure time of 8 seconds

A two second exposure of a fire poi ball dance

A fair ride taken with a 2/5 second exposure.

A photograph of the Forth Rail Bridge with an exposure time of 13 seconds - the effect of a long exposure shot on moving water is to make it seem creamy and opalescent

There are numerous approaches or "compositional techniques" to achieving a sense of unity within an artwork, depending on the goals of the artist. For example, a work of art is said to be aesthetically pleasing to the eye if the elements within the work are arranged in a balanced compositional way.However, there are artists such as Salvador Dali whose sole aim is to disrupt traditional composition and challenge the viewer to rethink balance and design elements within art works.Conventional composition can be achieved by utilizing a number of techniques

Rule of thirds

The rule of thirds is a guideline commonly followed by visual artists. The objective is to stop the subject(s) and areas of interest (such as the horizon) from bisecting the image, by placing them near one of the lines that would divide the image into three equal columns and rows, ideally near the intersection of those lines.

Rule of odds

The rule of odds states that by displaying an odd number of objects, there is always one in the middle that is "framed" by the surrounding objects. This adds comfort to the artwork and is used in advertising quite often.

Rule of space

The rule of space applies to artwork (photography, advertising, illustration) picturing object(s): - to which the artist wants to apply the illusion of movement, or - which is supposed to create a contextual bubble in the viewer's mind.

This can be achieved by e.g. leaving white space in the direction the eyes of a portrayed person are looking at. Another example would be when picturing a runner, adding whitespace behind him rather than in front of him to indicate movement