Some cool ideal body measurements images:
Image by wallygrom
The jeeps gather to cross the Salar … they prefer to travel in pairs … if one breaks down, it is a long way from anywhere … and back in 1999 there were no mobile phones out there …
From Wikipedia –
Salar de Uyuni (or Salar de Tunupa) is the world’s largest salt flat at 10,582 square kilometers (4,086 sq mi). It is located in the Potosí and Oruro departments in southwest Bolivia, near the crest of the Andes, and is elevated 3,656 meters (11,995 ft) above the mean sea level.
The Salar was formed as a result of transformations between several prehistoric lakes. It is covered by a few meters of salt crust, which has an extraordinary flatness with the average altitude variations within one meter over the entire area of the Salar. The crust serves as a source of salt and covers a pool of brine, which is exceptionally rich in lithium. It contains 50 to 70% of the world’s lithium reserves, which is in the process of being extracted. The large area, clear skies and exceptional surface flatness make the Salar an ideal object for calibrating the altimeters of the Earth observation satellites. The Salar serves as the major transport route across the Bolivian Altiplano and is a major breeding ground for several species of pink flamingos.
Formation, geology and climate
Salar de Uyuni is part of the Altiplano of Bolivia in South America. The Altiplano is a high plateau, which was formed during uplift of the Andes mountains. The plateau includes fresh and saltwater lakes as well as salt flats and is surrounded by mountains with no drainage outlets.
The geological history of the Salar is associated with a sequential transformation between several vast lakes. Some 30,000–42,000 years ago, the area was part of a giant prehistoric lake, Lake Minchin. Its age was estimated from radiocarbon dating of shells from outcropping sediments and carbonate reefs and varies between reported studies. Lake Minchin (named after the Juan B. Minchin of Oruro) later transformed into paleolake Tauca having a maximal depth of 140 meters (460 ft), and an estimated age of 13,000–18,000 or 14,900–26,100 years depending on the source. The youngest prehistoric lake was Coipasa, which was radiocarbon dated to 11,500–13,400 years. When it dried, it left behind two modern lakes, Poopó Lake and Uru Uru Lake, and two major salt deserts, Salar de Coipasa and the larger Salar de Uyuni. Salar de Uyini spreads over 10,582 square kilometers (4,086 sq mi), which is roughly 25 times the size of the Bonneville Salt Flats in the United States. Lake Poopó is a neighbor of the much larger lake Titicaca. During the wet season, Titicaca overflows and discharges into Poopó, which, in turn, floods Salar De Coipasa and Salar de Uyuni.
Underneath the surface of the Salar is a lake of brine 2 to 20 meters (7 to 66 ft) deep. The brine is a saturated solution of table salt, lithium chloride and magnesium chloride in water. It is covered with a solid salt crust with a thickness varying between tens of centimeters to a few meters. The center of the Salar contains a few "islands", which are the remains of the tops of ancient volcanoes which were submerged during the era of lake Minchin. They include unusual and fragile coral-like structures and deposits that often consist of fossils and algae.
The area has a relatively stable average temperature with a peak at 21 °C (70 °F) in November-January and a low of 13 °C (55 °F) in June. The nights are however cold all through the year with temperatures between -9 and 5 °C (16 and 41 °F). The relative humidity is rather low and constant throughout the year at 30–45 %. The rainfall is also low at 1–3 millimeters (0.039–0.12 in) per month between April and November, but it may increase up to 70 millimeters (2.8 in) in January. However, except for January, even in the rainy season the number of rainy days is below 5 per month.
Salt production at the Salar
The Salar contains large amounts of sodium, potassium, lithium and magnesium (all in the chloride forms of NaCl, KCl, LiCl and MgCl2, respectively), as well as borax. Of those, lithium is arguably most important as it is a vital component of many electric batteries. With estimated 5,400,000 tonnes (5,310,000 LT; 5,950,000 ST), Bolivia holds about half of the world’s lithium reserves; most of those are located in the Salar de Uyuni. Lithium is concentrated in the brine under the salt crust at a relatively high concentration of about 0.3%. It is also present in the top layers of the porous halite body lying under the brine; however the liquid brine is easier to extract, by boring into the crust and pumping out the brine. The brine distribution has been monitored by the Landsat satellite and confirmed in ground drilling tests. Following those findings, an American-based international corporation has invested 7 million to develop lithium extraction. However, lithium extraction in the 1980s and 1990s by foreign companies met strong opposition of the local community. Despite their poverty, locals believed that the money infused by mining would not reach them. There is currently no mining plant at the site, and the Bolivian government doesn’t want to allow exploitation by foreign corporations. Instead, it intends to build its own pilot plant with a modest annual production of 1,200 tonnes (1,200 LT; 1,300 ST) of lithium and to increase it to 30,000 tonnes (30,000 LT; 33,000 ST) tonnes by 2012.
Salar de Uyuni is estimated to contain 10 billion tonnes (9.8 billion LT; 11 billion ST) tonnes of salt, of which less than 25,000 tonnes (25,000 LT; 28,000 ST) is extracted annually. All miners working in the Salar belong to Colchani’s cooperative.
Because of its location, large area and flatness, the Salar is a major car transport route across the Bolivian Altiplano.
Salar is salt flat in Spanish and Uyuni originates from the Aymara language and means a pen (enclosure). Thus Salar de Uyuni can be loosely translated as a salt flat with enclosures, the latter possibly referring to the "islands" of the Salar. Uyuni is also the name for a town of 10,600 people, which serves as a gateway for tourists visiting the Salar.
Aymara legend tells that the mountains Tunupa, Kusku and Kusina, which surround the Salar, were giant people. Tunupa married Kusku, but Kusku ran away from her with Kusina. Grieving Tunupa started to cry while breast-feeding her son. Her tears mixed with milk and formed the Salar. Many locals consider the Tunupa an important deity and say that the place should be called Salar de Tunupa rather than Salar de Uyuni.
Flora and fauna
The Salar is virtually devoid of any wild life and vegetation. The latter is dominated by giant cacti (Echinopsis atacamensis pasacana, Echinopsis tarijensis, etc.). They grow at a rate of about 1 centimeter (0.39 in) per year to a length of about 12 meters (39 ft). Other shrubs include Pilaya, which is used by locals to cure catarrh, and Thola (Baccharis dracunculifolia), which is burned as a fuel. Also present are quinoa plants and quenua bushes.
Every November, Salar de Uyuni is the breeding grounds for three species of pink South American flamingos: the Chilean, Andean and rare James’s Flamingos, their color presumably originating from feeding on pink algae. There are about 80 of other bird species present, including the horned coot, the Andean goose and the Andean Hillstar. Andean fox (culpeo) is a representative animal, and the "islands" of Salar (in particular the Incahuasi island, which is also called Isla del Pescadores) host a colony of rabbit-like viscachas.
Salar de Uyuni attracts tourists from around the world. As it is located far from the cities, a number of hotels have been built in the area. Due to lack of conventional construction materials, many of them are almost entirely (walls, roof, furniture) built with salt blocks cut from the Salar.
The first such hotel was erected in 1993-1995 in the middle of the salt flat, and soon became a popular tourist destination. However, its location in the center of a desert produced sanitary problems, as most waste had to be collected manually. Mismanagement caused serious environmental pollution and the hotel had to be dismantled in 2002. New salt hotels were built near the periphery of the Salar, closer to roads, in full compliance with environmental rules.
One major tourist attraction is an antique train cemetery. It is 3 kilometers (1.9 mi) outside Uyuni and is connected to it by the old train tracks. The town served in the past as a distribution hub for the trains carrying minerals enroute to Pacific Ocean ports. The rail lines were built by British engineers arriving near the end of the 19th century and formed a sizeable community in Uyuni. The engineers were invited by British-sponsored Antofagasta and Bolivia Railway Companies, which is now Ferrocarril de Antofagasta a Bolivia. The rail construction started in 1888 and ended in 1892. It was encouraged by Bolivian President Aniceto Arce, who believed Bolivia would flourish with a good transport system, but it was also constantly sabotaged by the local Aymara indigenous Indians who saw it as an intrusion into their lives. The trains were mostly used by the mining companies. In the 1940s, the mining industry collapsed, partly because of mineral depletion. Many trains were abandoned, producing the train cemetery. There are proposals to build a museum from the cemetery.
Some Earth observing satellites need to be precisely calibrated in terms the distance measurement while in orbit. For example, the primary objective of the NASA’s Geoscience Laser Altimeter System (GLAS), which is installed on the Ice, Cloud and land Elevation Satellite (ICESat), is to detect changes in ice sheet elevations of as little as 1.5 centimeters (0.59 in) per year, over 100-by-100-kilometre (62 × 62 mi) area. A common approach for calibrating the satellite elevation measurements is to compare them to an accurately surveyed terrestrial reference target. Salt flats are ideal for this purpose because they are large, stable surfaces having strong reflection, similar to that of ice sheets. Salar de Uyuni is especially suitable because it is the largest salt flat on Earth. In the low-rain period of from April to November, its skies are very clear, and the air is dry (relative humidity is about 30%, rainfall is roughly 1 millimetre or 0.039 in per month). Absence of large industries and the high elevation also contribute to the clarity of the air. The Salar also has a stable surface which is smoothed by seasonal flooding (water dissolves the salt surface and thus keeps it leveled). As a result, the variation in the surface elevation over the 10,582-square-kilometer (4,086 sq mi) area of Salar de Uyuni is less than 1 meter (3 ft 3 in), and there are square kilometers there which are flat within a few centimeters. The surface reflectivity (albedo) for ultraviolet light is relatively high at 0.69 and shows variations of only few percent during the daytime. Combination of all these features make Salar de Uyuni about five times better for satellite calibration than the surface of an ocean. Using Salar de Uyuni as the target, ICESat has already achieved the short-term elevation measurement accuracy of below 2 centimeters (0.79 in).
With the use of modern GPS technology, it can now be proved that the Salar de Uyuni is not perfectly flat. New measurements revealed previously missed features resembling ridges, hills, and valleys measuring only millimeters in height. They originate from the variation in material density, and thus the gravitational force, beneath the Salar’s sediments. Just as the ocean surface rises over denser seamounts, the salt flat surface also rises and falls to reflect the subsurface density variations.
Image by hopeless128
Canon launches the new Digital Rebel XSi or EOS 450D – digital camera and photography newsCanon ‘Beefs Up’ the New Rebel With Optically Image Stabilized Lens Kit and ‘Pro’ Features
Canon U.S.A., Inc.’s EOS Rebel series of digital single lens reflex cameras – the cameras that defined and refined what it means to be an "entry level" digital SLR – have now redefined the gateway prowess and "pro-ness" of the DSLR category with the introduction of the line’s new leader, the 12.2-megapixel EOS Rebel XSi camera. Incorporating a number of high-end functions and technology found in Canon’s professional SLR models, the EOS Rebel XSi camera boasts an improved autofocus sensor, enhanced 14-bit A/D conversion, an advanced Live View function, and the proprietary DIGIC III image processor. When paired with any of the more than 60 compatible Canon EF and EF-S lenses, including optically image stabilized EF-S lenses like the EF-S18-55mm f/3.5-5.6 IS – now included in the EOS Rebel XSi kit – or the new EF-S55-250mm f/4-5.6 IS, the EOS Rebel XSi DSLR delivers images that will delight and inspire family and friends at an entry level price tag.
"This new EOS Rebel XSi camera is the answer for those who have been waiting to make the leap from digital point-and-shoot to digital SLR or from an older SLR to the latest generation of advanced technology, while still including the creative controls their old camera afforded them," states Yuichi Ishizuka, senior vice president and general manager, Consumer Imaging Group, Canon U.S.A.
Luxury Feel and Function
At first glance, one notices the Rebel XSi’s large, 3-inch LCD monitor, enhanced from the 2.5-inch screen on the Digital Rebel XTi model. The larger 230,000 pixel screen makes it easier for users to review images and scroll through the Rebel XSi camera’s menus. The larger-sized display provides the ability to use a larger font size for menu text, making it easier than ever to read settings and options. The new screen also features a broadened color gamut, seven brightness settings for easy viewing under a variety of shooting conditions and a wide viewing perspective in all directions.
The EOS Rebel XSi camera features a substantial yet streamlined profile, with curved edges, contoured surfaces, conveniently placed controls and comfortably constructed rubber grip and thumb rest that all contribute to fatigue-reducing hand fit. The camera body is constructed of a rugged yet lightweight combination of stainless steel and polycarbonate embedded with glass fiber. The chassis exterior is enrobed in a durable ABS and Polycarbonate resin and offered in a choice of silver or black finishes.
Improved Image Quality
At the heart of the new EOS Rebel XSi is its newly designed 12.2 megapixel APS-C size Canon CMOS sensor. This new sensor employs large microlenses over each pixel to reduce noise and enhance sensitivity up to ISO 1600, which is ideal for high-quality images in low light. The APS-C size sensor retains a 1.6x focal length conversion factor compared to full-frame digital image sensors or 35mm film format cameras.
Another image quality enhancement is the upgrade of the Analog-to-Digital (A/D) conversion process to a 14-bit A/D processor. The inclusion of the 14-bit A/D process means the Rebel XSi camera records up to 16,384 colors per channel and allows the camera to produce images with finer and more accurate gradations of tones and colors. This is ideal for shooting outdoors where subtle hue changes in sky, water or foliage can really add to an image.
The Canon EOS Rebel XSi DSLR also incorporates the optional Highlight Tone Priority and High-ISO Noise Reduction functions first introduced in 2007 with the EOS-1D Mark III Professional Digital SLR and now available for the first time in an entry level Canon digital SLR camera. Additionally, the new camera is equipped with Canon’s Auto Lighting Optimizer technology, which corrects image brightness and contrast automatically. Introduced last year in the EOS 40D camera, this valuable optional feature now works in all exposure modes and utilizes Face Detection technology to prevent underexposure with backlit faces.
DIGIC III Image Processor
If the 12.2-megapixel APS-C size CMOS sensor is the heart of the camera, then Canon’s DIGIC III processor is the brain. The latest generation of Canon’s proprietary image processing engine, DIGIC III technology ensures that the fine details and natural colors of the images are optimally recorded. The DIGIC III processor also manages the camera’s efficient energy consumption and high-speed signal processing performance. The EOS Rebel XSi is the first model in the Rebel series to incorporate DIGIC III.
Enhanced Live View
Introduced in 2007 on the EOS-1D Mark III DSLR, this function makes its debut in an entry level Canon DSLR with the EOS Rebel XSi camera. Live View allows users to frame shots through the LCD screen rather than the viewfinder. Going beyond the manual focus and phase-detection AF capabilities of earlier EOS models with Live View, the EOS Rebel XSi camera adds a new "Live Mode" contrast-detection AF function that allows the camera to focus automatically during Live View without lowering the reflex mirror.
Improved Autofocus and Framing Rate
The EOS Rebel XSi Digital SLR utilizes a precise nine-point Autofocus (AF) system featuring a newly developed AF sensor that improves the camera’s subject detection capabilities compared to earlier models. The new Rebel XSi DSLR provides a cross-type AF measurement at the center that’s effective with all EF and EF-S lenses, while providing enhanced precision with lenses having maximum apertures of f/2.8 or faster. The cross-type AF measurement reads a wider variety of subject matter than conventional single-axis AF sensors and thus increases the new camera’s ability to autofocus quickly and accurately. The EOS Rebel XSi is also the fastest firing Rebel model to date, capable of continuously capturing 3.5 frames per second for bursts of up to 45 images in large/fine JPEG mode and 6 frames in RAW mode. The faster frame rates and finer focusing capabilities of the Rebel XSi together with its impressive image burst rate will help photo enthusiasts preserve family milestones or capture split second sports action at just the right moment.
EOS Integrated Cleaning System
The new Rebel XSi DSLR utilizes Canon’s EOS Integrated Cleaning system, first introduced on the EOS Rebel XTi camera. The camera’s Self-Cleaning Sensor Unit shakes dust particles off of the low-pass filter in front of the sensor. The dust is then trapped by an adhesive along the base, preventing it from causing further nuisance. Cleaning is engaged each time the camera is powered up or shut down or manually through the "clean now" function.
The second part of the cleaning system involves post processing with a compatible personal computer and the supplied Digital Photo Professional software. Here the camera maps any spots that may remain on the sensor, saving it as Dust Delete Data and subsequently subtracting dust spots from the final image during post processing. A third option includes a manual sensor cleaning function which raises the mirror and allows users to clean dust that may have stuck to the low-pass filter.
Back to the Basics
In keeping with its EOS system heritage, the new Canon EOS Rebel XSi camera is equipped with a host of useful creative controls, including shutter speeds ranging from 1/4000 sec. to 30 sec. plus Bulb, a choice of four metering patterns including 4% spot metering (another first for the Rebel series), a wide range of exposure modes from fully automatic to fully manual, depth of field preview, mirror lock and much more. The new camera is fully compatible with all Canon EF and EF-S lenses, as well as EX-series Speedlites, an optional Battery Grip, and remote control and viewfinder accessories.
A departure from previous EOS Digital Rebel models, which accommodated CF type memory cards, the new EOS Rebel XSi camera utilizes SD and SDHC memory cards including those with capacities higher than 2GB, making it the perfect upgrade for users already equipped with SD cards from point-and-shoot model cameras. Additionally, the EOS Rebel XSi camera utilizes Canon’s new high-capacity LP-E5 lithium ion battery pack, which provides 50% more exposures per charge than earlier models with virtually no increase in size or weight.
In the Box
Expected to ship in April 2008 the Canon Rebel XSi camera is available in body-only configuration which includes a rechargeable battery pack and charger, USB and video cables, a neckstrap, an EOS Solutions Disk CD, and a 1-year Canon U.S.A., Inc. limited warranty. The new camera will also be available in a lens kit version which includes everything in the body-only kit plus the EF-S18-55mm f/3.5-5.6 IS zoom lens. The two versions carry estimated retail prices of 9.99 and 9.99, respectively.