|
Photographic Images
Photography , is the process of recording pictures by means of capturing light on a light-sensitive medium, such as a film or electronic sensor. more...
 Home
Art
 Digital Art
Drawings
Folk Art
Mixed Media
Paintings
Photographic Images
Posters
Prints
Sculpture, Carvings
Self-Representing Artists
Bead Art
Candle & Soap Making
Ceramics, Pottery
Decorative, Tole Painting
Drawing
Embroidery
Floral Crafts
Framing & Matting
General Art & Craft Supplies
Glass Art Crafts
Handcrafted Items
Leathercraft
Metalworking
Mosaic
Painting
Paper Crafts
Ribbon
Rubber Stamping & Embossing
Scrapbooking
Sewing
Shellcraft
Woodworking
Yarn
Light patterns reflected or emitted from objects expose a sensitive silver halide based chemical or electronic medium during a timed exposure, usually through a photographic lens in a device known as a camera that also stores the resulting information chemically or electronically.
The word "photography" comes from the French photographie which is based on the Greek words φως phos ("light"), and γραφίς graphis ("stylus", "paintbrush") or γραφή graphê ("representation by means of lines" or "drawing"), together meaning "drawing with light." Traditionally, the product of photography has been called a photograph, commonly shortened to photo.
Photographic cameras
The camera or camera obscura is the image-forming device, and photographic film or a silicon electronic image sensor is the sensing medium. The respective recording medium can be the film itself, or a digital electronic or magnetic memory.
Photographers control the camera and lens to "expose" the light recording material (such as film) to the required amount of light to form a "latent image" (on film) or "raw file" (in digital cameras) which, after appropriate processing, is converted to a usable image. Modern digital cameras replace film with an electronic image sensor based on light-sensitive electronics such as charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) technology. The resulting digital image is stored electronically, but can be reproduced on paper or film.
The controls usually include but are not limited to the following:
Focus of the lens;
Aperture of the lens – adjustment of the iris, measured as f-number, which controls the amount of light entering the lens. Aperture also has an effect on focus and depth of field, namely, the smaller the opening , the less light but the greater the depth of field--that is, the greater the range within which objects appear to be sharply focused.;
Shutter speed – adjustment of the speed (often expressed either as fractions of seconds or as an angle, with mechanical shutters) of the shutter to control the amount of time during which the imaging medium is exposed to light for each exposure. Shutter speed may be used to control the amount of light striking the image plane; 'faster' shutter speeds (that is, those of shorter duration) decrease both the amount of light and the amount of image blurring from subject motion or camera motion.;
White balance – on digital cameras, electronic compensation for the color temperature associated with a given set of lighting conditions, ensuring that white light is registered as such on the imaging chip and therefore that the colors in the frame will appear natural. On mechanical, film-based cameras, this function is served by the operator's choice of film stock. In addition to using white balance to register natural coloration of the image, photographers may employ white balance to aesthetic end, for example white balancing to a blue object in order to obtain a warm color temperature.;
Metering – measurement of exposure at a midtone so that highlights and shadows are exposed according to the photographer's wishes. Many modern cameras feature this ability, though it is traditionally accomplished with the use of a separate light metering device.;
ISO speed – traditionally used to set the film speed of the selected film on film cameras, ISO speeds are employed on modern digital cameras as an indication of the system's gain from light to numerical output and to control the automatic exposure system. A correct combination of ISO speed, aperture, and shutter speed leads to an image that is neither too dark nor too light.;
Auto-focus point – on some cameras, the selection of a point in the imaging frame upon which the auto-focus system will attempt to focus. Many Single-lens reflex cameras (SLR) feature multiple auto-focus points in the viewfinder.;
Read more at Wikipedia.org
|
|
