Photography Glossary
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- Cleaning brush
- Lens cleaner
The PhotographyTalk glossary is a collection of common photography terms that will help you master different concepts and learn how to become a better photographer. Entries in this photography glossary link to PhotographyTalk articles as applicable, that way you have instant access to more details about some of the more complex topics. Our photography glossary is periodically updated to add new photography terms and update old ones. Consider this glossary your one-stop shop for learning essential photography terms!
35mm Equivalent
The of the field of view seen through a digital camera as compared to the field of view in a 35mm traditional film camera.
Active Auto-Focus
A camera function that bounces an invisible beam of light off the subject. By measuring the precise distance between the camera and the object, the lens is automatically set for the correct focus.
AE Lock
A basic camera setting that locks the current exposure settings
AMOLED (Active Matrix Organic Light Emitting Diode)
Display technology using organic compounds to create a digital matrix. It uses less power and refreshes more quickly than LCD. It is frequently used in mobile equipment giving devices longer battery life, but it is hard to see the screen in direct sunlight.
Analog to Digital (ADC) Converter
A device that converts analog data (data a computer can't read) into digital data (data a computer can read).
Aperture
The size of the lens diaphragm opening is its aperture. Referred to as f-stops, apertures are generally written as numbers, as shown in the diagram. The smaller the number, the bigger the aperture opening, the larger the number, the smaller the aperture opening. Likewise, the larger the aperture opening, the shallower the depth of field will be. When shooting portraits, for example, an aperture of f/1.8 would generally be more appropriate than an aperture of f/22 because f/1.8 is a larger aperture opening that will create a blurry background.
Aperture Priority Mode
Aperture priority mode is a camera setting that allows the photographer to choose the aperture while the camera will set the shutter speed for the right exposure. This gives the photographer control over depth of field. Typically represented as A or AV on digital cameras.
Aspect Ratio
The ratio of the width to height of an image or screen.
Aspherical Lens
Elements in this type of lens have a profile that is not in proportion of a sphere or cylinder. This corrects for focusing aberrations, especially when using wide apertures. The glass for these lenses is typically molded instead of grounded adding to the cost of the lens.
Audio Video Interleave (AVI)
File type created by Microsoft for the recording and playback of audio and video using the Windows operating system. These files have almost CD quality sound but are very large.
Autofocus
Camera setting that allows the camera to focus the image for the best quality. Point and shoot cameras are mostly autofocus only, while DSLRs and mirrorless cameras have various autofocus modes, including allowing for AF to be disabled. Many DSLRs and mirrorless cameras have changeable AF settings allowing for greater flexibility.
Automatic Exposure Bracketing (AEB)
Camera setting that directs the camera to take three or more photos at various exposure settings, automatically. This is especially useful when shooting images to form composite HDR images or under unusual lighting conditions. Using AEB is faster than changing the settings manually for each shot that will create a composite image.
AVCHD (Advanced Video Coding High Definition)
High definition video format that is owned by Sony and Panasonic. It is the standard for high definition camcorders but some DSLR manufacturers also use this type of file for recording video. This type of file uses the extension .MTS or .m2ts, and there is no difference in the contents of the files. Apple does not support this type of video so it needs to be converted to a different file type before it can be edited on a Mac.
Back Light
Backlighting is used to separate the subject from the backdrop or background, giving more dimension to the photo. Backlighting emanates from behind the subject, so viewers are looking toward the light while the subject is between the viewer and the light source.
Barrel Distortion
A type of lens distortion that causes the lines of an image to bow outward. This is commonly associated with wide-angle lenses because of the curvature of the glass optics of the lens. Fisheye lenses take advantage of this distortion to create images like the one seen here. Note how the flat surface of the water is bowed due to barrel distortion.
Bit
Short for binary digit. The smallest unit used to measure computer data. It contains the single binary value of 0 or 1.
Bit Depth
Also known as color depth, bit depth is color information that is stored in a digital image. The higher the bit depth of an image, the more colors it can store. For example, 8-bit images have 256 possible colors while 24-bit images have over 16 million colors. Increasing the bit depth adds better color quality to an image but it greatly increases the file size.
Bitmap
Bitmap (BMP), or raster, is a way to store images as individual pixels. Each pixel is assigned a color and used to form the image. These types of images are easily changed in a wide variety of editing software.
Blooming
Term used to describe the loss of image definition due to excessive brightness. This can be equated to overexposure in film photography.
Buffer
A camera’s buffer memory is used temporarily to store information or data about a picture before moving it to the memory card.
Candid
Candid photographs are generally considered those of a subject that is unaware of the camera. As a result, candid images usually capture spontaneous expressions and activity.
Center-Weighted Light Metering
In center-weighted metering, the camera’s light meter reads the central area of the image where the primary subject is located. It also evaluates the light levels of the surrounding space to select an average exposure. Because this metering mode is 'center-weighted,' the subject must be somewhere in the center of the shot for the meter to give the proper exposure settings. It is just one of several metering modes on modern cameras.
Color Channels
The way color information is stored in images. The number of color channels depends on the type of file that is being used. RGB images have three color channels: red, blue, and green. CMYK images have four color channels: cyan, magenta, yellow, and black. Grayscale images have one channel. Each channel controls its own color, and when all channels are combined, they create a full-color image when using RGB or CMYK.
Chromatic Aberration
Also known as color fringing, chromatic aberration occurs when the colors of a subject are incorrectly refracted by the lens. This results in a mismatch of colors on the sensor. It can be seen as a ring of color separating a dark area of a picture from a light area that surrounds it. This can be easily removed with photo-editing software.
Complementary Metal-Oxide Semiconductor (CMOS) Sensor
An integrated light-sensitive circuit that displays and stores pixels (image data) as an electrical charge with the intensity of the related color on the color spectrum. This technology is the main sensor in most digital cameras due to its fast speed and low power consumption.
CMYK
This acronym is for Cyan, Magenta, Yellow, and BlacK. CMYK is a subtractive color spectrum for printing. This is considered the correct color spectrum for printing and is the most widely used. Images need to be converted from RGB (Red Green Blue) to CMYK to be printed. Most home printers do this automatically.
Codec (Compression and Decompression)
Video compression algorithm that compresses an audio and video signal, records it at a manageable file size, then decompress the data for editing, viewing, or transferring.
Color-Filter Array
Also known as Color Filter Mosaic. Tiny color filters placed over the pixels of a sensor to capture color information. The most common type of array is called the Bayer Array, a mosaic of alternating red-green and blue-green filters.
Compact Digital Camera
Also known as point-and-shoot cameras, compacts are typically the lowest cost and smallest in size and weight. That size and lower price means some limitations, such as a fixed lens or a small zoom lens. Image quality is usually not as good as one will find with a DSLR or mirrorless camera.
Compression
A way to minimize the file size of images without reducing the quality of the image to an unacceptable level. This allows for more images to be stored on a device or image card. It also allows for faster loading speeds on the internet. Common image compression formats are JPEG, GIF, and PNG.
Dark Frame
This is a method to reduce image noise, or hot pixels, that can appear in a picture taken with a long exposure time. Once the picture is shot, a second picture is taken of just a black image. The easy-to-see image noise in the dark frame, which matches the noise's locations in the first picture, can then be eliminated electronically.
Depth of Field
The distance between the closest and furthest objects in a photograph that appear to be in sharp focus is referred to as the depth of field. Shallow depth of field has a smaller area of focus which is obtained by using a large aperture like, f/1.8. A shallow depth of field is common in portrait photography because it results in a blurry background that helps set the portrait subject apart in the frame, as shown above. In this image, note that the depth of field is so shallow that the woman’s arms are in focus but her face is not.
More depth of field is achieved by adjusting the aperture to a smaller opening. For example, where f/1.8 results in a shallow depth of field f/22 results in a large depth of field. Larger depth of fields are often used in landscape photography such that the entire landscape from front to back is in focus, as shown above.
Diaphragm
This is another name for the aperture or opening of a lens.
Digital IS (Image Stabilization)
This software is included in many digital cameras to counteract an unsteady camera that causes photo blur. To do so, Digital IS may change ISO and shutter speed settings, which could reduce the quality of your photos.
Digital Zoom
The camera’s software recreates the zooming effect of a lens by enlarging the image. Digital zoom degrades the quality of an image, unlike optical zoom.
Diopter Adjustment
This allows the photographer to customize the viewfinder to adjust the focused image without using eyeglasses.
DPI (Dots Per Inch)
DPI is the measurement of the number of dots in every inch of a reproduced image, such as scanning or printing, or the resolution of a computer screen. For example, many of the scanners you can buy to connect to your computer are 1,200 DPI, which will create a sharp image.
DSLR Camera (Digital Single-Lens Reflex)
This type of camera uses a mirror to reflect the light coming through the lens to the optical viewfinder using a prism or other mirrors. The photographer sees directly through the lens of the camera and when the shutter is pressed, the mirror flips up to reveal the sensor.
Effective Resolution
A camera's image sensor contains a limited number of pixels, which is the sensor's overall resolution. The senor uses only some of those pixels to create a digital photo. That is the effective resolution. Effective resolution is a better method to compare one camera to another.
Evaluative or Matrix Light Metering<
Evaluative (Canon) or Matrix (Nikon) light metering is the basic light metering system in most DSLRs in which the frame is divided into zones. The light in each zone is analyzed and the camera creates the most balanced exposure for the whole scene. It is just one of several metering modes on modern cameras.
EXIF (Exchangeable Image File)
A file containing the specific exposure data of a digital photograph, such as ISO speed, shutter speed, aperture, white balance, camera model and make, date and time, lens type, focal length and other data.
Expanded Auto Focus Point
Some DSLR cameras have this setting that makes the autofocus point space bigger. A moving object doesn't need to be in the exact center of the focus point to take the desired photograph.
Exposure Bracketing
Taking multiple photographs, usually 3 or more, that are exposed using different settings. One image is taken at the correct exposure, the next image is underexposed, and the final image is overexposed.
These exposures can be combined to create an HDR photograph, giving the image the correct exposure for the highlights, midtones and shadows.
Extension Tube
A spacer that fits between the lens and the camera body that contains no glass or optical elements. An extension tube alters the minimum focal distance of a lens allowing for macro photographs to be taken.
Fill Light
The fill light is a secondary source to the key, or main, light. The fill light fills the lighting 'gaps' of the key light, softening the direct shadows it causes and balancing the contrast, so it's visible, but subtler.
This gray-toned filter absorbs a set amount of light entering a camera lens. Solid neutral density filters (at left in the image above) allows the photographer to use a wider range of apertures and shutter speeds in bright conditions. For example, a photographer can blur the movement of water from a waterfall or waves.
Graduated neutral density (at right, above) filters are a gradient from dark to light allowing the photographer to create landscape images with a properly exposed sky and land. The darker upper portion of the filter blocks out light from the bright sky while the clear bottom portion of the filter has no impact on the exposure of the landscape.
Filters: Polarizing
This filter helps minimize glare, creates better definition in clouds, and can help saturate colors. Polarizing filters rotate allowing the photographer control of how the light is filtered. Depending on how much light is filtered from the image, it may require exposure compensation.
Filters: UV and Skylight Filters
These filters help cut through the haze and airborne pollutants leaving images more clear.
UV filters are usually clear but depending on the strength of the UV coating it may have an amber appearance that may require exposure compensation.
Skylight filters have a magenta cast that is preferable when shooting color slide film for portraits. Skylight filters are equal to UV filters in cutting through atmospheric haze.
Fisheye Lens
This is an extreme variation of a wide-angle lens. A common wide-angle lens size is 20mm, while a fisheye lens is typically 8mm to 10mm. A fisheye lens creates a rounded image (like the one above) that shows the area in front of, to the side of, and even a bit behind the camera.
Flash
A device used by a photographer to produce a burst of light to illuminate a scene. This device can be built into the camera or can be an external device
Flip LCD
A flexible LCD viewfinder on a digital camera that can be moved away from the camera into various positions. A photographer can still compose an image and take a picture from an unusual angle.
Focus Assist
Using a small light, usually built into the body of the camera above the lens, the camera can better focus in low-light conditions.
Four-Thirds System
Olympus and Kodak created this DSLR photography technology for newer camera bodies and interchangeable lenses that makes them fully digital. This technology is resulting in DSLR camera and lens that are smaller, such as low-cost compact digital cameras.
Frame Rate
A measurement of how many frames of a video are viewed or sent per second.
Geotagging
Information about the location, time and altitude of each photo. That data is part of each digital image. A digital camera and a GPS (global positioning system) unit are connected to collect the geotag data.
Gigabyte (GB)
One gigabyte equals approximately one billion bytes of stored data (photos, videos, words, art, etc.) 'Giga' comes from the Greek word, gigas, or giant.
Gimbal-Head Tripod
A tripod with a gimbal head moves more freely to provide additional angles, which can make it easier to shoot certain kinds of photos, such as wildlife or objects in motion.
Graphics Interchange Format (GIF)
A lossless compression for image files using indexed color. A GIF can have a maximum of 256 colors.
Gray Level
Brightness level of a pixel or group of pixels.
Grayscale
The spectrum of shades of gray and black and white of an image.
Halftone Image
HDMI (High Definition Multimedia Interface)
HDMI cables are utilized in audio and video interfaces for transmitting data. HDMI is designed to quickly transfer uncompressed video and either compressed or uncompressed audio from a source (i.e., a digital camera) to an output device, like a computer or TV.
High Dynamic Range (HDR) Digital Photography
An HDR photograph is actually composed of a number of different images blended together. Each image is taken in rapid succession, but utilizes different exposure settings. This results in each of the individual photos being exposed for different areas of the scene. For example, an HDR image of a landscape might have one image that’s exposed for the bright sky, one that’s exposed for the shaded areas, and one that’s exposed for the dark shadows. By blending these images together, the HDR process creates a single image that’s well-exposed throughout.
Histogram
When you select 'histogram' from the menu of your camera, you'll see the image you want to photograph, with date, time, exposure settings and other information displayed on the screen. Next to the image is the histogram graph.
As you can see in the chart, the histogram shows you the black to gray to white tones of your picture in a vertical range. The technology recognizes the tonal levels of areas within the image, according to the number of pixels for each black, gray or white tone.
The high points on a histogram represent the tones with the greatest number of pixels. When there are more high points to the left of the histogram, your digital image has many dark tones. More high points to the right represents an image with many lighter tones. Ideally, you want the histogram to display a bell-shaped curve, with the largest number of pixels in the midtone area.
Using a histogram is far more accurate for determining the exposure levels of an image than relying on the viewfinder or the LCD when shooting in live view.
Hot Shoe
The hot shoe is a metal bracket on top of your camera where you attach an external flash unit or other hot shoe compatible accessories. When properly seated, the unit makes a 'hot' connection to the camera's electronics, so if using a flash, it is automatically triggered when you press the shutter button.
Hyperfocal Distance Technique
Hyperfocal distance is the distance at which the lens’s focus provides the greatest depth of field. From an optical standpoint, it is the closest distance at which you can focus while maintaining acceptable sharpness to infinity.
This point varies depending on the aperture and the focal length being used. For example, if shooting at f/1.2, the hyperfocal distance would be further away than if shooting at f/22 because at f/1.2, there is a much smaller depth of field. Likewise, if shooting at 24mm, the hyperfocal distance might be just 10-20 feet in front of you, but if shooting at 300mm, the hyperfocal distance might be several hundred feet in front of you.
The size of the camera’s sensor also influences where the hyperfocal distance will be. The larger the sensor, the nearer that point will be. For example, if shooting an image with a full frame camera, the hyperfocal distance will be closer to you than if you shoot the same scene with a smartphone.
This technique is often used in landscape photography when there are objects both near the camera and far away in the scene - such as a plant in the foreground and mountains in the background. Using the hyperfocal distance technique allows you to get both elements sharp.
To determine hyperfocal distance, you can utilize a chart like the one below, or use a hyperfocal distance app on your smartphone.
When using the hyperfocal distance technique, the image will be sharp from halfway in front of the hyperfocal distance point to infinity. This means that if the hyperfocal distance point is 20 feet away, the image will be acceptably sharp from 10 feet to infinity.
So, let’s say you’re using a full frame camera with an aperture of f/11 and a focal length of 24mm. According to the chart above, the hyperfocal distance is 5.7 feet. If you change the aperture to f/16 and the focal length to 50mm, the hyperfocal distance is 17 feet.
To use this technique, you can put your lens in manual focus and use the distance scale on top of the lens to focus at the correct distance. If your lens doesn’t have a distance scale, you can leave it in autofocus and approximate the correct distance using the viewfinder by focusing the lens on an object roughly the correct distance away.
ICC Profile (The International Colour Consortium)
This organization was established in 1993 and created a cross-platform, vendor-neutral standard for color management. By using an ICC profile, color data created on one device can be translated by another device in its native color space. This allows end-users of images to move color profiles between different devices and operating systems, which results in much greater flexibility when working with digital images.
Infinity
Infinity is a setting at one end of the distance scale on a lens (on Canon lenses, infinity is on the far right; on Nikon lenses, it’s on the far left). It is a symbol that looks like the numeral 8 on its side. At that setting, the farthest object in your photo will be in focus.
Infrared (IR)
Infrared light exists at a wavelength that makes it invisible to the human eye. However, in photography, special infrared film or digital imaging sensors can be used to record infrared light in the near-infrared spectrum (as opposed to the far-infrared spectrum which involves thermal imaging).
For photography purposes, the wavelengths of infrared light that are recorded are often in the 700 nanometer to 900 nanometer range. Infrared photos have a dreamy, surreal look - skin is very smooth and milky, black tones appear to be gray or white, and vegetation looks white, as just a few examples.
Interlaced
This describes how an image sensor processes the data of any image by collecting the odd lines and then the even lines of data. When these images are displayed (i.e., on a website), an initial degraded image is loaded quickly and then progressively improves in quality in order to speed up the process of displaying images, particularly when slow internet connections are being used.
Intervalometer
Also known as an interval meter or interval timer. Intervalometers are used to trigger exposures at specific time intervals. It is commonly used in time-lapse photography. A simple example of an intervalometer is the self-timer function on modern cameras. Most DSLR cameras have a delay of up to 30 seconds but can create longer exposures when using the Bulb setting.
ISO
ISO is a standardized system of film speed. It is a combination of two older systems, ASA and DIN. ISO does take its name from the International Standards Organization but doesn’t have any relation to the company.
In film photography, ISO is the light sensitivity rating of the film's emulsion. Lower ISO (Ex. 100) means the film will be less sensitive to light than a higher ISO (Ex. 1600). Light-sensitive silver halide crystals are layered to create the emulsion of the film. The layers of crystals of a high ISO film are coarser and larger. Light is recorded more quickly by the larger grains. This gives you the ability to photography in situations with less light. Low ISO films have smaller, finer crystals that will take longer to record the light giving a much smaller grain pattern.
By increasing the ISO, you will be able to capture lower light situations but there will be a loss of sharpness, saturation, and dynamic range. The film grain of a high ISO will be most apparent in the highlights.
In digital photography, ISO is a camera setting that will lighten or darken an image. Unlike film photography, this is applied after the image has been exposed. This is called applied gain.
Your camera’s sensor has one sensitivity. It is measured in very small units, Mpix. These tiny pixels capture the light. For example, a camera with a 20 Mpix sensor has 20 million pixels to record the light when you release the shutter. Most DSLRs record the image at its base ISO of 100.
When light hits the camera’s sensor, each pixel measures and records the intensity of the light by counting the number of photons reaching it. The RAW data captured by the camera is an aggregate of the voltage values recorded by the Mpix.
The ISO gain applied to your image is boosted by the factor of the difference between the base ISO and the set ISO. For example, an image taken at 200 ISO will have the brightness boosted by a factor of two because the camera first records the image at a base ISO of 100.
Increasing the ISO on your camera allows you to photograph in low-light situations. Like with film, the higher the ISO, the less detail, less saturation, and less dynamic range. The noise of high digital ISO will be most apparent in the shadows.
JPG
JPG or JPEG is a file type for images. It is also a means of lossy image compression.
The degree of compression can be adjusted. The more an image is compressed, it decreases the image quality but makes the file size smaller.
Unlike RAW files, JPG files are immediately shareable and viewable.
Kelvin
https://www.istockphoto.com/photo/kelvin-temperature-colours-gm646405090-117228913
Kelvin (K) is the standard unit of measurement used to describe the hue or color of a light source. The higher the number, the more blue the light will be. The lower the number, the more orange the light will be.
Light sources with a K higher value are closer to natural sunlight, which is around 5250K. A blue color cast appears with values above 5250K. An incandescent bulb is 2600k, giving the light a yellow-orange cast.
Key Light
The main and most important light in a lighting set up. It highlights the form of the subject, giving it depth and dimension. Silhouettes can be obtained by omitting the key light.
Landscape View
The viewfinder of the camera is oriented so its rectangle is wider than it is tall. Holding a camera horizontally will produce an image in landscape view.
Lens
A photographic lens is used to focus light to create an image.
A photographic lens contains one or more optics forming an element. These elements can be manipulated to create optical effects.
A lens body houses the glass elements and the focusing mechanism. Moving the focusing mechanism changes the position of the elements to create an image on the sensor or film.
Lens Cap
The protective coverings for the back and front of any lens.
Lens Cleaning Kit
Tools used to clean dust, debris, oils and other particles from lenses.
Kits usually contain:
Lens Depth-of-Field Scale
The depth of field scale is located near the focusing ring of the lens. It shows the near and far limits of sharpness for an image.
Lens Distance Scale
A scale on lenses showing the minimum and maximum focusing distance.
Lens Flare
Lens Flare is an artifact caused when a bright light entering a camera lens hits the sensor and scatters. A bright source of light that doesn’t form an image like the sun, full moon, or bright artificial light can be the source of a lens flare.
It can appear as starbursts, determined by the size and shape of the camera’s aperture, or it can wash out a photograph, lessening the contrast.
This can be a deliberate choice the photographer makes adding drama to a photograph. For example, by placing the subject between the light and camera, a lens flare can be artificially created.
Lens Focal length
The focal length of the lens is the distance between the lens and the image sensor when the subject is in focus, usually expressed in millimeters. This is the lens’ angle of view.
A telephoto lens, or a lens with a focal length greater than 50mm, has a smaller angle of few and the subject appears larger in the frame. A wide-angle lens, or one with a focal length less than 50mm, has a wider area captured and the subject can appear smaller.
Lens Hood
A piece of equipment that can be attached to the front of a lens that will block sunlight or other light from entering the lens. This can prevent lens flare or glare.
Lens (Wide-Angle)
A lens with a wide field of view and a short focal length. It captures more of the scene surrounding a subject when moving in close.
An APS-C, or cropped sensor camera, will need a 28mm or wider lens to get a wide-angle effect.
35mm or wider is the focal length for a wide-angle lens on a Full Frame camera
Lens (Zoom)
Any lens that can change its angle of view or focal length by moving the optics is a zoom lens.
Lithium ION (Li-ion)
High energy density rechargeable batteries used in most consumer electronics.
Lossless
Data compression algorithms that perfectly reconstruct the original data from the compressed data. This results in a much larger file size.
RAW image data saved by a camera is typically lossless. Other lossless compression files are: ZIP, PNG, and GIF.
Lossy
A compression algorithm where data is lost or removed from the original file. This will result in smaller file sizes but a loss of quality.
Common Lossy compression files are: JPEG, MP3, and MPEG.
Macro Photography
Close up photography of tiny subjects. If the subject on the negative or sensor is lifesize or greater, it is considered a macro image. Depth of Field is greatly limited in macro photography, and often the focal plane is just millimeters in depth.
Manual Focus
The photographer physically moves the focusing rings on lens to select the focus of the image. This can be especially useful in Macro Photography when fine tuning focus is important.
Megabyte (MB)
One megabyte equals approximately one million bytes of stored data (photos, videos, words, art, etc.). 'Mega' comes from the Greek word, megas, meaning large.
Megapixel (MP)
One megapixel is equal to one million pixels. Your digital camera's image sensor captures each picture you take as a series of extremely tiny points, or pixels. The resolution of each picture is measured in megapixels.
Memory Card
A storage device that provides a non-volatile and permanent way to store media or data files.
Memory Card Erase Function
This is a feature of most DSLR cameras that allows you to erase pictures and other files from your memory cards so you can use them again. Read your camera's manual because the deletion process is different for many cameras. Typically, you perform this task in the main menu and have access to the steps in playback mode, although this may also vary from camera to camera.
Memory Card Format Function
A feature of most DSLR cameras that allows you to format new memory cards or those that have been erased. Read your camera's manual because formatting the memory card is more absolute, as that function will erase everything, even your protected pictures. Formatting also reconstructs the file system, but with new directories and folders. If your memory cards are slow or you're shooting digital photos most of the time, then be sure to format the cards occasionally during the year.
Memory Card Reader
A device used to access data stored on a memory card.
Model Release
A standard photography document that provides the photographer with legal permission to use another person's image for commercial purposes or to submit pictures to a photo contest.
Moir
An effect that can occur if the subject of a photograph has highly repetitive details, including dots, lines, or patterns, that are greater than the sensor resolution. A visual pattern of wavy rainbow lines will appear where the sensor is unable to properly record the image.
Multi-Zone Focusing
An autofocus mode that determines what the camera will use as the focus point in the frame: center, upper left, upper right, lower right, lower left, right or left. This method of focusing is commonly used in point-and-shoot cameras. It can also be inaccurate when there are multiple subjects in a scene.
Noise Reduction
In-camera noise reduction can help reduce the color variations in the shadows of long exposures and high ISO images.
Most post-processing software also has ways to reduce or eliminate noise from photographs.
The best way to limit noise is to shoot photographs with the lowest ISO possible. Using strobes, flashes, and a wide aperture can also help to minimize noise.
Optical IS (Image Stabilization)
Techniques used to reduce image blurring as a result of motion of the camera during an exposure. OIS happens in the lens, stabilizing the image before it is projected onto the sensor.
Optical Zoom
An optical zoom allows you to adjust the optics of a lens to fill the frame with a subject. This is done by physically moving the zoom ring on a lens, and is therefore a true zoom that gives the highest quality images. Digital zoom, on the other hand, is nothing more than the camera cropping the edges of the image and making the center portion larger. As a result, digital zoom often results in poor image quality, like pixelated images.
Overexposure
When photographic mediums are exposed to too much light. Images will have a loss of detail in the highlights, leaving the image “blown out.” If an image is too overexposed, it cannot be corrected in post-processing software because the image doesn’t contain enough information to recover those details.
Passive Auto-Focus
When a digital camera uses a non-intrusive way to to focus on a scene by mainly detecting contrast. It will find the area with maximum contrast closest to the camera and focus there. This system fails when there is not sufficient contrast in a scene or in low ambient light.
Photo-Editing Software
Software used to enhance or manipulate digital images. There are many types of programs available from inexpensive phone apps and free software to more expensive, powerful software for computers. Many paid software companies offer a free trial so photographers can explore the program to see if it as the right features before committing to purchasing it.
Pin Cushioning
An image is distorted causing the lines in the photograph to curve toward the center giving a pinched look. This distortion is caused by poorly-made telephoto lenses, particularly zoom lenses. Most photo editing software contains correction filters for this and other types of distortion.
Pixel
A shortened version of 'picture element,' which is the smallest component of any digital picture displayed on a screen (LCD or CRT monitors). Millions of pixels are needed to create an image. A pixel can display only one color at a time. The color of a pixel easily blends with those around it creating various shades and hues.
Portable Network Graphics (PNG)
A PNG is a lossless form of compression for image files commonly used on the internet. PNG files support RGBA colors, or alpha channel, and also provides the ability to make pixels transparent.
Portrait View
The viewfinder of the camera is oriented so its rectangle is taller than it is wide. Holding a camera vertically will produce an image in portrait view.
Processor
A chip in a digital camera that directs the creation and management of your pictures as well as the functions of the memory card, the LCD, and the analog/digital converter.
QuickTime
Software developed by Apple in the early 1990s that allows a computer to play video files with an audio track. It is compatible with both Windows and Apple devices. In 2016, Apple stopped support for QuickTime on Windows computers because of security vulnerabilities.
Rangefinder
A camera focusing system using a ring to line up superimposed images. The photographer doesn’t look through the lens to focus. Rangefinder cameras a quieter, lighter and have sharper images than SLR cameras because there is no mirror to move. One of the biggest disadvantages is you don’t know exactly what you are going to get. Since you don't look through the lens parallax can be a big problem. There is also no depth of field indicated in the viewfinder.
Red-Eye
When a subject has bright red pupils in a photograph. This is caused by a built-in or pop- up flash creating a bright light close to and almost parallel to the optical path of the lens. Light from the flash is reflected back to the camera after bouncing off the retina of the subject.
Reflector
Any kind of surface that helps you to reflect light onto a specific portion of a picture, such as a person's face in a shadow. Reflectors are available as professional photography equipment or can be made DIY out of items as simple as a white piece of cloth or aluminum foil.
Response Times
This refers to the amount of time required for various functions on your digital camera (startup, shutter lag and pauses between shots) to work. Each type of camera has different response times.
RGB
Red, Green, Blue. A system of representing colors on a computer or other screens. Different combinations of red, green and blue light produce colors. RGB is an additive model for producing color. By combining red, green and blue light at 100%, white light is created.
Rule of thirds
A composition technique where the photographer divides the frame, either in their mind or physically, into thirds creating a grid of nine squares. Important elements of the photograph are placed on or near, the intersection of the grid lines. This technique works best when composing an image in-camera, but can be used to crop images in post production.
Scanner
A device that captures images from physical items, like photographs or documents, and converts it to a digital file. Scanners are usually peripheral devices used in tandem with a computer and specialized software.
Self-Timer
A camera feature that allows you to choose the time the shutter is released. This allows the photographer time to move into the image (i.e., for a group photo). Additionally, the self-timer helps minimize camera movement when taking a long exposure. For example, if the timer is set to five seconds, any vibrations caused by the photographer pressing the shutter button should dissipate by the time the shutter is triggered.
Sepia
A monochrome image created in brown instead of grayscale that creates a warmer feeling image. This technique was used in darkrooms to tone metallic silver prints. The sepia toning process changes the silver to silver sulfide, helping the print become more archival by resisting the effects of atmospheric sulfur compounds and other environmental pollutants.
Most modern photo editing software contains ways to recreate the effect digitally.
Shooting Modes
Pre-programmed settings on digital cameras that allow photographers to choose the best shutter speed and aperture combinations for common types of photographs, such as landscapes and portraits.
Shooting Modes * Beach Mode
Camera setting that adjusts the exposure of a beach environment, where light reflects brightly off the water and sand.
Shooting Modes * Burst, or Continuous Shooting, Mode
Camera setting that will rapidly take a series of photos when the shutter button is pressed or held down. Also called sports mode.
Shooting Modes * Fireworks Mode
Camera setting that adjusts the exposure to take photos of fireworks.
Shooting Modes * Foliage Mode
Camera setting that boosts the saturation of a photograph.
Shooting Modes * Indoor Mode
Camera setting that adjusts the shutter speed and white balance for shooting indoors.
Shooting Modes * Kids and Pets Mode
Camera setting that adjusts shutter speed and may pre-focus to overcome shutter lag when taking photos of subjects that won’t stay still.
Shooting Modes * Landscape Mode
Camera setting that adjusts the aperture to a large f-stop creating more depth of field in a photograph.
Shooting Modes * Macro Mode
Camera setting that adjusts the aperture to create a shallow depth of field helping to create close up photographs. This mode works best when paired with a lens that has macro capabilities as not all lenses will allow you to take macro photographs.
Shooting Modes * Movie Mode
Camera setting that allows for video and sound capture with mid-range quality.
Shooting Modes * Night Mode
Camera setting that adjusts the shutter speed to allow more light to hit the sensor. It also functions as a Shutter Sync allowing your camera to work with external strobes or a flash.
Shooting Modes * Panoramic/Stitch Mode
This setting allows you to take multiple shots of a wide panorama, as in a landscape photo, and then combine those images into one, using photo-editing software.
Shooting Modes * Program Mode
Camera setting, indicated by a P on the camera dial, that gives the photographer control of part of the exposure, such as ISO, and built-in flash, but the camera will choose the aperture and shutter speed. Program mode allows you to override the aperture and shutter speed selections made by the camera should you wish.
Shooting Modes * Snow Mode
Camera setting that adjusts the exposure of a snowy environment, where light reflects brightly off the snow.
Shooting Modes * Sports Mode
Camera setting that will rapidly take a series of photos when the shutter button is pressed or held down. Also called continuous shooting mode.
Shooting Modes * Underwater Mode
Camera setting that is sets the exposure for the unique light conditions underwater. Used with cameras that are waterproof.
Shutter Lag
The delay, measured in milliseconds, between when the shutter release is pressed and when the photograph is recorded by the camera. This delay can lead to missing the crucial moment of the photograph if the subject is moving quickly. If the amount of shutter lag is known, it can be compensated for by pressing the shutter release early.
Shutter Priority Mode
This setting allows you to set the desired shutter speed for an exposure and the camera will choose the aperture for a correct exposure. Represented by Tv or S symbol on most digital cameras.
Shutter Speed
The length of time the shutter of a camera is open exposing the sensor to light. Shutter speed settings are typically displayed on a camera in fractions of seconds, such as 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, etc., or whole seconds, such as 1, 5, 10 or 30. Cameras may also have a 'B' setting, which is 'bulb.' At this setting, the shutter will remain open until you release the shutter button. Long shutter speeds blur the motion of moving subjects, as shown above. Short shutter speed tend to freeze movement.
Sightline
Using the gaze of the subject of a photograph as a compositional element. Humans naturally want to look at the faces of others and will follow the direction of a subject’s gaze. This gives the photographer a powerful tool to direct the viewers to important elements of an image.
Silhouette
A photographic technique where the subject of a photograph is brightly lit from behind, with little to no light in front, creating a well-defined area of black in an image where none of the details or features of the silhouetted subject are visible. Using highly recognizable subjects like trees, people, or animals will create better silhouettes.
Silica Gel Packets
Typically placed in the bottom of a camera bag to help absorb moisture, which could otherwise enter your camera and lens and cause damage.
Spirit level
A small level, similar to a carpenter's level, that you can attach to the top of your camera body to help you keep your camera level and shoot level pictures.
Spot metering
Using the camera’s light meter to measure the light of a scene in a small area of a photograph. This is useful when taking photographs of a subject in front of a high-contrast background. It is just one of several metering modes on modern cameras.
Startup-Time
The time it takes for a camera to completely power on.
Studio Lighting
Photographic lights that are color balanced to daylight that can be used inside to light subjects. Umbrellas or softboxes are used to diffuse the light.
Terabyte (TB)
This is the next level of storage space after a gigabyte. A terabyte is approximately 1 trillion bytes, which is the equivalent of 1,000 GB (gigabytes).
TIFF
Tagged Image File Format. This file format is largely used by 3D applications and in the medical imaging, printing and publishing industries. TIFF uses Lempel-Ziv-Welch Lossless compression method. The file size is significantly larger than JPEGs and has the ability to store multiple layers.
Transfer Rate
This is the speed your camera's memory card writes, or transfers, data or information about a picture from the camera to the card.
Tripod
A three-legged stand for supporting a camera or other apparatus.
UDMA (Ultra Direct Memory Access) Technology
This technology increases the data transfer rate of your camera's memory card even more. UDMA also increases the transfer speed of data from your camera to your computer. You need an UDMA-enabled memory card reader, however.
Underexposure
A photo that wasn't exposed to enough light, leaving it very dark and with few recognizable details.
USB (Universal Serial Bus)
A common interface that lets computers and peripheral devices communicate.
Viewfinder
The part of a camera that a photographer looks through to compose and focus the subject of a photograph. These can be made from glass as in a rangefinder or DSLR camera, or an LCD screen on a mirrorless camera.
White Balance
Adjusting colors of a digital image to look more natural. This gets rid of color casts from different sources of light that have a color other than white.
Adjusting colors of a digital image to look more natural. This gets rid of color casts from different sources of light that have a color other than white.