Exposure Compensation

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PHOTO TERMS
AE: Automatic Exposure - A camera in automatic exposure mode
automatically calculates and adjusts exposure settings to match (as closely
as possible) the subject's mid-tone to the mid-tone of the photograph. For
most cameras this means using an on-board TTL exposure meter.
AV:Aperture priority mode gives the photographer manual control of the
aperture, whilst the camera automatically adjusts the shutter speed to
achieve the exposure specified by the TTL meter.
AE Lock: Used to hold an automatically controlled shutter speed and/or
lens aperture, in case you need to recompose your picture but want to
retain an previous exposure reading.
Aperture: Is the numerical designations indicating the size of the aperture
that governs the amount of light entering the lens. (f/2.8, f/4, f/5.6, f/8, f/11,
f/16, etc.) also referred to as f-stops.
Aspect Ratio:the proportion of an image size given in terms of the
horizontal length vs. the vertical height. A 5x7 image has a ratio of 7:5.
Available Light: Refers to the natural light or existing lighting conditions
under which an image is made.
B (Bulb): At the B setting, the shutter remains open as long as the shutter
release button remains fully depressed.
Body: Refers to a SLR camera without a lens.
Bounce Card: a small white card used to redirect the stream of light and
soften the quality of light being emitted from a strobe or flash unit.
Bracketing: A common photographic approach whereby the photographer
will take several frames of the same scene at different exposure settings.
Composition: the arranging of informational and/or artistic elements with
a viewfinder so as to form a unified whole or image that imparts
information or an idea.
Computer Enhancement: refers to contrast adjustments, toning, color
correcting dodging and burning to prepare an image or photograph for
production.
Computer Image: pure digital illustration -- created on a computer to
achieve a particular effect -- which either uses photographs as its base
material, or is so photorealistic that it may be perceived as being real. The
images are not real events that have occurred in history but rather are
manifestations of ones imagination.
Depth of Field: simply put, it is the apparent sharpness of a photograph
considering the distance between the nearest and farthest elements that
appear to maintain acceptable sharpness and clarity.
Digital Photograph: A photograph that has been captured electronically
on a hard drive (storage device) or converted from film to digital format
through an electronic scanning process.
Dodging and Burning: Is the lightening (burning) and darkening
(dodging) of areas of the photograph by altering the amount of light hitting
the print.
Dynamic Range: refers to the varying gray values, or the spread of gray
values, in an image that are possible reproduction. Am image with a high
dynamic range suggests a wide number of gray levels and is normally
associated with good contrast levels.
EOS (Canon): Electronic Optical System; Canon's current line of autofocus
cameras and accessories. Was introduced in 1989 to facilitate the new
Canon autofocus system.
E-TTL (Canon): Evaluative, through-the-lens flash metering.
EV: Exposure Value denotes all combinations of a camera's shutter speed
and relative aperture that give the same exposure. In an attempt to simplify
choosing among combinations of equivalent camera settings, the concept
was developed by the German shutter manufacturer Friedrich Deckel in
the 1950s. Exposure value also is used to indicate an interval on the
photographic exposure scale, with 1 EV corresponding to a standard
power-of-2 exposure step, commonly referred to as a stop.
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. To
work with exposure, one must understand how aperture, shutter speed and
ISO interrelate. This is often called the Trinity of Exposure.
Exposure Compensation: is a technique for adjusting the exposure
indicated by a photographic exposure meter, in consideration of factors
that may cause the indicated exposure to result in a less-than-optimal
image. Factors considered may include unusual lighting distribution,
variations within a camera system, filters, non-standard processing, or
intended underexposure or overexposure. Cinematographers may also
apply exposure compensation for changes in shutter angle or film speed
(as exposure index), among other factors. Use this link to see an
interactive simulation of Exposure Composition.
F-Stops: Is the numerical designations indicating the size of the aperture
that governs the amount of light entering the lens. (f/2.8, f/4, f/5.6, f/8, f/11,
f/16, etc.) See Aperture.
Fast Lens: Refers to lenses that open to a large f-stop (aperture setting).
The larger f-stops (smaller numbers, i.e. f/2.8) allow greater amounts of
light into the lens.
Fill-Flash: is a photographic technique used to brighten deep shadow
areas, typically outdoors on sunny days, though the technique is useful
any time the background is significantly brighter than the subject of the
photograph, particularly in backlit subjects. To use fill flash, the aperture
and shutter speed are adjusted to correctly expose the background, and
the flash is fired to lighten the foreground.
Fisheye: is a wide-angle lens that takes in a broad, panoramic and
hemispherical image. Originally developed for use in meteorology to study
cloud formation and called "whole-sky lenses", fisheye lenses quickly
became popular in general photography for their unique, distorted
appearance. They are often used by photographers shooting broad
landscapes to suggest the curve of the Earth.
Flare: Image degradation caused by stray light which passes through the
lens but is not focused to form the primary image. Often caused by light
bouncing off internal air-to-glass surfaces.
Focal Length: The distance from the optical center of a lens to the image
plane when the lens is focused to infinity.
Hot Shoe: is a mounting point on the top of a camera to attach a flash unit.
In-Camera Manipulation: refers to certain measures and steps taken by
the photographer to produce a desired effect, such as filers, lens choice,
angles, and/or multiple exposures.
ISO: International Standards Organization; the number represents the
film's sensitivity to light. A higher ISO number indicates the film is more
sensitive and requires less light for a proper exposure. Check this link to
see the difference between ISO speeds.
Juxtaposition: the act of placing or positioning items in the image area of
a photograph side by side or next to one another to illustrate some
comparison.
Long Glass: refers to a Telephoto lens that magnifies the subjects in an
image and covers a narrow angle of view of a scene.
Latitude: The variance from "proper" exposure, which will still provide
acceptable results.
Matrix: This metering mode was first introduced by the Nikon FA, where it
was called Automatic Multi-Pattern metering. On a number of cameras this
is the default/standard metering setting. Here the camera measures the
light intensity in several points in the scene, and then combines the results
to find the settings for the best exposure.
Moment: Photographers seek to capture the natural and candid events of
history. Their quest to capture a "moment" comes from the famous French
documentary photographer Henri Cartier-Bresson and his consistent ability
to capture the decisive moment in time without disrupting a particular
situation.
Photo Illustration: is either a set-up photograph (usually in a studio with
no digital alteration) that is illustrative in nature and is clearly out of the
realm of reality. Traditionally, it is an approach used for fashion, food and
product photographs.
Photojournalism: is the craft of employing photographic storytelling to
document life: it is universal and transcends cultural and language bounds.
Pixel: fundamental picture element of a digital photograph. A single digital
or electronic photograph is made up of thousands of pixels.
Rule of Thirds: is a compositional rule of thumb in visual arts such as
painting, photography and design.[1] The rule states that an image should
be imagined as divided into nine equal parts by two equally-spaced
horizontal lines and two equally-spaced vertical lines, and that important
compositional elements should be placed along these lines or their
intersections.[2] Proponents of the technique claim that aligning a subject
with these points creates more tension, energy and interest in the
composition than simply centering the subject would.
Seeing Light: refers to the ability of the photographer to see and capture
the effects of light and shadow in the world around us.
Shooter: A term that has long been associated with newspaper
photographers. Today the term is rather controversial. Many journalist feel
that the term does not acknowledge the valuable contributions of the
photojournalist or news photographer.
Shutter Speed: is a common term used to discuss exposure time, the
effective length of time a camera's shutter is open. Shutter speed controls
the motion seen in a photo. A faster shutter speed will stop action, while a
slower shutter speed will blurr movement.
SLR: Single Lens Reflex; a camera with one lens (as opposed to Twin
Lens Reflex like the Rolleiflex) that involves a mirror and prism that the
viewer looks through (as opposed to a point and shoot or rangefinder
where the viewer looks through a separate viewfinder.
Soft Vs. Sharp: soft is a description for an image that is blurred or out of
focus, just as sharp describes an image or part of an image that shows
crisp detail and precise texture.
Spot Meter: The camera will only measure a very small area of the scene
(between 1-5% of the viewfinder area). This will typically be the very center
of the scene, but some cameras allow the user to select a different offcenter spot, or to recompose by moving the camera after metering.
Strobe: is an electronic flash device that provides artificial, supplementary
lighting.
Sunny-16 Rule: A guideline that states that you can expose a normal
scene, lit by bright sunlight, at an aperture of f16 and a shutter speed
equivalent to the film speed (ISO or ASA) being used.
TTL: Through-the-lens; commonly used when referring to metering
through the lens as opposed to via a separate meter. Effective for fill-flash
and other tricky lighting situations.
TV: Shutter priority mode gives manual shutter control, with automatic
aperture compensation. In each case, the actual exposure level is still
determined by the camera's exposure meter.
Transmit: The process of sending a photograph from one location to
another via computer or cell phone.
Wild Art: Stand-Alone, Feature Shot, Enterprise art are found moments
that are intended to be realistic slices of everyday life.
Zone System: An early application of exposure compensation was the
Zone System developed by Ansel Adams and Fred Archer.[2] Although the
Zone System has sometimes been regarded as complex, the basic
concept is quite simple: render dark objects as dark and light objects as
light, according to the photographer's visualization. Developed for blackand-white film, the Zone System divided luminance[# 5] into 11 zones, with
Zone 0 representing pure black and Zone X representing pure white. The
meter indication would place whatever was metered on Zone V, a medium
gray. The tonal range of color negative film is slightly less than that of
black-and-white film, and the tonal range of color reversal film and digital
sensors even less; accordingly, there are fewer zones between pure black
and pure white. The meter indication, however, remains Zone V. The
relationship between exposure compensation and exposure zones is
straightforward: an exposure compensation of one EV is equal to a change
of one zone; thus exposure compensation of −1 EV is equivalent to
placement on Zone IV, and exposure compensation of +2 EV is equivalent
to placement on Zone VII. The Zone System is a very specialized form of
exposure compensation, and is used most effectively when metering
individual scene elements, such as a sunlit rock or the bark of a tree in
shade. Many cameras incorporate narrow-angle spot meters to facilitate
such measurements. Because of the limited tonal range, an exposure
compensation range of ±2 EV is often sufficient for using the Zone System
with color film and digital sensors.
Zoning: Presetting the focus to a particular spot to photograph action so
that the area where the action is anticipated to take place will be in focus.
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