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The metering system in a digital camera measures the amount of light in the scene and calculates the best-fit exposure value based on the metering mode explained below. Automatic exposure is a standard feature in all digital cameras. All you have to do is select the metering mode, point the camera and press the shutter release. Most of the time, this will result in a correct exposure . (www.dpreview.com....ing_01.htm)
This is probably the most complex metering mode, offering the best exposure in most circumstances. Essentially, the scene is split up into a matrix of metering zones which are evaluated individually. The overall exposure is based on an algorithm specific to that camera, the details of which are closely guarded by the manufacturer. Often they are based on comparing the measurements to the exposure of typical scenes. (www.dpreview.com....ing_01.htm)
Probably the most common metering method implemented in nearly every digital camera and the default for those digital cameras which don't offer metering mode selection. This method averages the exposure of the entire frame but gives extra weight to the center and is ideal for portraits (www.dpreview.com....ing_01.htm)
Spot metering allows you to meter the subject in the center of the frame (or on some cameras at the selected AF point). Only a small area of the whole frame is metered and the exposure of the rest of the frame is ignored. This type of metering is useful for brightly backlit, macro, and moon shot (www.dpreview.com....ing_01.htm)
Shutterspeeds are expressed in fractions of seconds , typically as (approximate) multiples of 1/2, so that each higher shutterspeed halves the exposure by halving the exposure time: 1/2s, 1/4s, 1/8s, 1/15s, 1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s, 1/2000s, 1/4000s, 1/8000s, etc. Long exposure shutterspeeds are expressed in seconds , e.g. 8s, 4s, 2s, 1 (www.dpreview.com....eed_01.htm)
A perture refers to the size of the opening in the lens that determines the amount of light falling onto the film or sensor . The size of the opening is controlled by an adjustable diaphragm of overlapping blades similar to the pupils of our eyes. Aperture affects exposure and depth of field (www.dpreview.com....ure_01.htm)
The maximum aperture of a lens is also called its lens speed . Aperture and shutterspeed are interrelated via exposure . A lens with a large maximum aperture (e.g. f/2) is called a fast lens because the large aperture allows you to use high (fast) shutterspeeds and still receive sufficient exposure . Such lenses are ideal to shoot moving subjects in low light conditions (www.dpreview.com....ure_01.htm)
When setting up for bracketing you can usually select the number of frames to be taken (typically 2, 3 or 5), the exposure setting and the order in which to take the shots (eg. 0,-,+ or -,0,+ etc.). It is important to note that the values are exposure compensation values (www.dpreview.com....ing_01.htm)
Photog. an instrument that measures the intensity of light striking, or reflecting from, the subject, used to find the correct exposure settings; light met (www.yourdiction....sure-meter)
Flash output compensation is similar to exposure compensation and allows you to preset an adjustment value for the flash output power. Some digital cameras allow you to set this value using the familiar EV range (+/-2 EV), others simply have high, normal , and low settings. This feature is useful to compensate when the cameras flash metering was not perfect and caused under- or overexposure (www.dpreview.com....ion_01.htm)
Cumulative sun exposure causes mainly basal cell and squamous cell skincancer, while episodes of severe sunburns, usually before age 18, can causemelanoma later in life. Other less common causes are repeated X-ray exposure and occupational exposure to certain chemicals (www.webmd.com....kin-cancer)
The camera's metering system will sometimes determine the wrong exposure value needed to correctly expose the image. This can be corrected by the EV Compensation feature found in prosumer and professional cameras. Typically the EV compensation ranges from -2.0 EV to +2.0 EV with adjustments in steps of 0.5 or 0.3 EV. Some digital SLRs have wider EV compensation ranges, e.g. from -5.0 EV to +5.0 E (www.dpreview.com....ion_01.htm)
Automatic Exposure lock is the ability to lock exposure settings aperture and shutterspeed calculated by the camera over a series of images. This setting is useful when shooting images which will be stitched together into a panorama because stitching is much easier if each image has the same exposure (www.dpreview.com....ock_01.htm)
The firm has decades of experience in trying asbestos cases for tens of thousands of plaintiffs. In doing so, we developed a state-of-the-art Asbestos Exposure Database (www.weitzlux.com....77310.html)
Virtually everyone who is diagnosed with mesothelioma got sick because of their exposure to asbestos. The only way to contract asbestosis is from inhaling asbestos dust and fibers over a long period of time (www.weitzlux.com....77310.html)
For asbestos-related lung cancer, your doctor will carefully review your job history and perform medical tests to confirm that your asbestos exposure caused you to develop lung cancer (www.weitzlux.com....77310.html)
âThis risk from limited exposure was recognized many decades ago when reports of mesothelioma, from household exposure s of spouses and children and neighborhood exposure s from proximity to asbestos plants, appeared in the medical and scientific literature. We have represented many such asbestos victims and the current findings bear out the extent of the continuing asbestos disaster .â - Jerry Kristal, Weitz Luxenberg asbestos trial attorne (www.weitzlux.com....77310.html)
Our asbestos attorneys are committed to helping those diagnosed with mesothelioma, lung cancer or asbestosis because of secondary or limited exposure to asbestos (www.weitzlux.com....77310.html)
This book is what I had expected clear explanation on how to choose the creative exposure . As a novice in SLR, I find this book a must before read other books (www.amazon.com....69-3904444)
I have read many books on photography, and this book has been the only one that made sense of two words you see in all other books: "correct exposure ". Read mor (www.amazon.com....69-3904444)
This book is what I had expected clear explanation on how to choose the creative exposure . As a novice in SLR, I find this book a must before read other book (www.amazon.com....23-3107200)
I have read many books on photography, and this book has been the only one that made sense of two words you see in all other books: "correct exposure ". Read more (www.amazon.com....23-3107200)
D ouble Exposure Two is a revised and expanded version of DoubleExposure, issued in 1971. The original book, considered a classic,is scarce because half the 2,000 copies burned in a warehouse fireand it was never reprinted. Consequently, this publication is mostwelcom (www.city-gallery.com....osure.html)
Definition: A technique used in cognitive-behavioral therapy (also known as CBT) for reducing fear and anxiety associated with situational triggers. The basic idea behind exposure is that the person becomes used to the situation to the point that it no longer provokes anxiety (socialanxietydisorder.about.com....posure.htm)
There are two broad types of exposure that differ in terms of intensity and how fast triggers are introduced. Intensive exposure , also known as flooding , typically involves rapid exposure to feared situations. Systematic desensitization involves gradual exposure coupled with relaxation exercises when anxiety levels become too great (socialanxietydisorder.about.com....posure.htm)
I often hear people ask when they should be HIV tested. They realize that an exposure to HIV requires an HIV test, but how long after the exposure should HIV testing occur? And is one HIV test enough to rule out an HIV infection. (aids.about.com....posure.htm)
* Noise exposure maps (NEMs) and land use information developed pursuant to part 150 are voluntarily prepared by airport sponsors, and not all airport sponsors have prepared them. (www.faa.gov....sure_maps/)
** This column identifies whether the airport has prepared a noise exposure map under part 150. If No appears, the FAA has not yet determined the NEM to be compliant with part 150. If âNAâ appears, the land use information is not from a part 150 study but from other sources, such as environmental analyses and/or airport master plans (www.faa.gov....sure_maps/)
HIV statistics tell the story of the HIV epidemic. How people are infected help us develop prevention tools and to whom we should target our prevention efforts. The following HIV statistics and AIDS data details the extent of HIV and AIDS among adults and adolescents and by exposure category (aids.about.com....posure.htm)
Exposure to small amounts of an ingredient in the synthetic chemical found in plastic acts like estrogen in the blood. Bisphenol-A has been found to increase the incidence of insulin resistance , diabetes and the problems that are associated with these such as high blood pressure and cholesterol problems (metabolicsyndrome.about.com....ndrome.htm)
The chemical acts on receptors on the beta cells in the pancreas that stimulate the secretion of insulin. Earlier studies in animals have shown evidence that exposure to the chemical early in life can lead to obesity and gestational diabetes in women. (metabolicsyndrome.about.com....ndrome.htm)
No-Observed-Adverse-Effect Level (NOAEL) The highest exposure level at which there are no biologically significant increases in the frequency or severity of adverse effect between the exposed population and its appropriate control; some effects may be produced at this level, but they are not considered adverse or precursors of adverse effects. (www.epa.gov/hg/exposure.htm)
Lowest-Observed-Adverse- Effect Level (LOAEL) The lowest exposure level at which there are biologically significant increases in frequency or severity of adverse effects between the exposed population and its appropriate control grou (www.epa.gov/hg/exposure.htm)
When elemental mercury is spilled or a device containing mercury breaks, the exposed elemental mercury can evaporate and become an invisible, odorless toxic vapor. This is especially true in warm or poorly-ventilated rooms or spaces. Sources of potential exposure to elemental mercury are described below (www.epa.gov/hg/exposure.htm)
When I saw this story in my local newspaper today, I knew that it had hit the big time. Its one of those stories that catches the attention of lay people because it has to do with the exposure of our magic secrets (magic.about.com....posure.htm)
When it comes to exposure , I think the best course is to ignore and adapt. When exposure occurs, downplay its importance and move on. I think that I have history on my side. For example, when millions watched the masked magician exposure s on television a decade ago, magicians were not put out of work. Admittedly, magicians did have to adapt. (magic.about.com....posure.htm)
Blog search engines, directories, and web-based RSS aggregators that have been scouted by the author to submit his blog/site/RSS feed and to obtain the maximum level of exposure inside the blogosphere. Brief instructions are included on how to get your site liste (www.masternewmedia.org....posure.htm)
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