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Light Tent
A light tent, a kind of photography light modifier, is a box used for taking photos of objects without casting shadows. It can, for example, be used to take pictures of a physical product for use in an encyclopedia, for documentation or for marketing. The combination of evenly distributed lighting and the diffusing material means that minimal shadows are cast, and it can appear as if the pictured product is "floating in nothing", and a neutral image without a disturbing background can be achieved. Glossy or reflective objects in particular can require a light tent in order to avoid unwanted reflections in the picture. Walls and materials The walls in the box is made of a diffusing material such that light spreads well when it hits the surface. White is the most commonly used color, but other colors can also be used. This contributes to uniform lighting of the object. For example, one can use matte white paper sheets, but felt or another types of matte textile can also function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DIY Lightbox
"Do it yourself" ("DIY") is the method of building, modifying, or repairing things by oneself without the direct aid of professionals or certified experts. Academic research has described DIY as behaviors where "individuals use raw and semi-raw materials and parts to produce, transform, or reconstruct material possessions, including those drawn from the natural environment (e.g., landscaping)". DIY behavior can be triggered by various motivations previously categorized as marketplace motivations (economic benefits, lack of product availability, lack of product quality, need for customization), and identity enhancement (craftsmanship, empowerment, community seeking, uniqueness). The term "do-it-yourself" has been associated with consumers since at least 1912 primarily in the domain of home improvement and maintenance activities. The phrase "do it yourself" had come into common usage (in standard English) by the 1950s, in reference to the emergence of a trend of people undertak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-point Lighting
Three-point lighting is a standard method used in visual media such as theatre, video, film, still photography, computer-generated imagery and 3D computer graphics. By using three separate positions, the photographer can illuminate the shot's subject (such as a person) however desired, while also controlling (or eliminating) the shading and shadows produced by direct lighting. Setup Key Light The ''key light'', as the name suggests, shines directly upon the subject and serves as its principal illuminator; more than anything else, the strength, color and angle of the key determines the shot's overall lighting design. In indoor shots, the key is commonly a specialized lamp, or a camera's flash. In outdoor daytime shots, the Sun often serves as the key light. In this case, of course, the photographer cannot set the light in the exact position they want, so instead arranges the shot to best capture the sunlight, perhaps after waiting for the sun to position itself just right. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightbox
A lightbox is a translucent surface illuminated from behind, used for situations where a shape laid upon the surface needs to be seen with high contrast. Types Several varieties exist, depending on their purpose: * Various backlit viewing devices: ** A container with several lightbulbs and a pane of frosted glass on the top. It is used by photography professionals viewing transparent films, such as slides. This device was originally used to sort photographic plates with ease. When laid flat, it may be called a light table. Generally, a lightbox uses light similar to daylight (5,000–6,000 kelvins (K)) and has uniform light strength on the glass pane. **In the form of vertical panels, they can also be found mounted on the walls of hospitals and medical offices to review X-ray images (X-ray illuminator). ** In the science field, lightboxes are often used for looking at bacterial growth and allow better visualization for PCR plates. ** A lighted display panel used for advert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Balance
In photography and image processing, color balance is the global adjustment of the intensities of the colors (typically red, green, and blue primary colors). An important goal of this adjustment is to render specific colors – particularly neutral colors like white or grey – correctly. Hence, the general method is sometimes called gray balance, neutral balance, or white balance. Color balance changes the overall mixture of colors in an image and is used for color correction. Generalized versions of color balance are used to correct colors other than neutrals or to deliberately change them for effect. White balance is one of the most common kinds of balancing, and is when colors are adjusted to make a white object (such as a piece of paper or a wall) appear white and not a shade of any other colour. Image data acquired by sensors – either photographic film, film or electronic image sensors – must be transformed from the acquired values to new values that are appropriate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Film Speed
Film speed is the measure of a photographic film's sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system introduced in 1974. A closely related system, also known as ISO, is used to describe the relationship between exposure and output image lightness in digital cameras. Prior to ISO, the most common systems were ASA in the United States and DIN in Europe. The term ''speed'' comes from the early days of photography. Photographic emulsions that were more sensitive to light needed less time to generate an acceptable image and thus a complete exposure could be finished faster, with the subjects having to hold still for a shorter length of time. Emulsions that were less sensitive were deemed "slower" as the time to complete an exposure was much longer and often usable only for still life photography. Exposure times for photographic emulsions shortened from hours to fractions of a second by the late 19th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Of Field
The depth of field (DOF) is the distance between the nearest and the farthest objects that are in acceptably sharp focus (optics), focus in an image captured with a camera. See also the closely related depth of focus. Factors affecting depth of field For cameras that can only focus on one object distance at a time, depth of field is the distance between the nearest and the farthest objects that are in acceptably sharp focus in the image. "Acceptably sharp focus" is defined using a property called the "circle of confusion". The depth of field can be determined by focal length, distance to subject (object to be imaged), the acceptable circle of confusion size, and aperture. Limitations of depth of field can sometimes be overcome with various techniques and equipment. The approximate depth of field can be given by: \text \approx \frac for a given maximum acceptable circle of confusion , focal length , f-number , and distance to subject . As distance or the size of the acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture
In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image of the aperture and focal length of an optical system determine the cone angle of a bundle of rays that comes to a focus in the image plane. An optical system typically has many structures that limit ray bundles (ray bundles are also known as ''pencils'' of light). These structures may be the edge of a lens or mirror, or a ring or other fixture that holds an optical element in place or may be a special element such as a diaphragm placed in the optical path to limit the light admitted by the system. In general, these structures are called stops, and the aperture stop is the stop that primarily determines the cone of rays that an optical system accepts (see entrance pupil). As a result, it also determines the ray cone angle and brightne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-number
An f-number is a measure of the light-gathering ability of an optical system such as a camera lens. It is calculated by dividing the system's focal length by the diameter of the entrance pupil ("clear aperture").Smith, Warren ''Modern Optical Engineering'', 4th Ed., 2007 McGraw-Hill Professional, p. 183. The f-number is also known as the focal ratio, f-ratio, or f-stop, and it is key in determining the depth of field, diffraction, and Exposure (photography), exposure of a photograph. The f-number is dimensionless number, dimensionless and is usually expressed using a lower-case Ƒ, hooked f with the format ''N'', where ''N'' is the f-number. The f-number is also known as the inverse relative aperture, because it is the Multiplicative inverse, inverse of the relative aperture, defined as the aperture diameter divided by focal length. The relative aperture indicates how much light can pass through the lens at a given focal length. A lower f-number means a larger relative apertur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelvin
The kelvin (symbol: K) is the base unit for temperature in the International System of Units (SI). The Kelvin scale is an absolute temperature scale that starts at the lowest possible temperature (absolute zero), taken to be 0 K. By definition, the Celsius scale (symbol °C) and the Kelvin scale have the exact same magnitude; that is, a rise of 1 K is equal to a rise of 1 °C and vice versa, and any temperature in degrees Celsius can be converted to kelvin by adding 273.15. The 19th century British scientist Lord Kelvin first developed and proposed the scale. It was often called the "absolute Celsius" scale in the early 20th century. The kelvin was formally added to the International System of Units in 1954, defining 273.16 K to be the triple point of water. The Celsius, Fahrenheit, and Rankine scales were redefined in terms of the Kelvin scale using this definition. The 2019 revision of the SI now defines the kelvin in terms of energy by setting the Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Temperature
Color temperature is a parameter describing the color of a visible light source by comparing it to the color of light emitted by an idealized opaque, non-reflective body. The temperature of the ideal emitter that matches the color most closely is defined as the color temperature of the original visible light source. The color temperature scale describes only the ''color'' of light emitted by a light source, which may actually be at a different (and often much lower) temperature. Color temperature has applications in lighting, photography, videography, publishing, manufacturing, astrophysics, and other fields. In practice, color temperature is most meaningful for light sources that correspond somewhat closely to the color of some black body, i.e., light in a range going from red to orange to yellow to white to bluish white. Although the concept of correlated color temperature extends the definition to any visible light, the color temperature of a green or a purple light rar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camera
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression of visual arts, media, entertainment, surveillance, and scientific research. The invention of the camera dates back to the 19th century and has since evolved with advancements in technology, leading to a vast array of types and models in the 21st century. Cameras function through a combination of multiple mechanical components and principles. These include exposure control, which regulates the amount of light reaching the sensor or film; the lens, which focuses the light; the viewfinder, which allows the user to preview the scene; and the film or sensor, which captures the image. Several types of camera exist, each suited to specific uses and offering unique cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photograph
A photograph (also known as a photo, or more generically referred to as an ''image'' or ''picture'') is an image created by light falling on a photosensitivity, photosensitive surface, usually photographic film or an electronic image sensor. The process and practice of creating such images is called photography. Most photographs are now created using a smartphone or camera, which uses a photographic lens, lens to focus the scene's visible spectrum, visible wavelengths of light into a reproduction of what the human eye would perceive. Etymology The word ''photograph'' was coined in 1839 by Sir John Herschel and is based on the Greek language, Greek φῶς ('':el:phos, phos''), meaning "light", and γραφή (''graphê''), meaning "drawing, writing", together meaning "drawing with light". History The first permanent photograph, a contact-exposed copy of an engraving, was made in 1822 using the Bitumen of Judea, bitumen-based "heliography" process developed by Nicéphore Niép ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
