Dark Frame - A noise reduction process whereby a camera takes a second exposure of a black frame after the camera takes a long exposure (1/2-second or longer) image. The image "noise" is easily identified in the black frame shot and is then electronically removed from the actual image. This helps reduce the amount of hot pixels that normally show up in long exposure shots from digital cameras. Decompression - The process by which the full data content of a compressed file is restored.
Dedicated Flash - Describes an electronic flash that is made to be used only with a specific model of camera. Canon, Nikon, Olympus and other cameras have specific electrical contacts in the hot shoe to pass TTL-metering and AF range data to/from the flash unit. You can not use a dedicated Canon flash on a Nikon camera for example.
Densitometer - A tool used to measure the amount of light that is reflected or transmitted by an object.
Diffusion Dithering - A method of dithering that randomly distributes pixels instead of using a set pattern. Digital Film - Term used to describe solid state flash memory cards.
Diffusion Dithering - A method of dithering that randomly distributes pixels instead of using a set pattern. Digital Film - Term used to describe solid state flash memory cards.
Digital Zoom - A digital magnification of the center 50% of an image. Digital zooms by nature generate less than sharp images because the new "zoomed" image has been interpolated.
Digitization - The process of converting analog information into digital format for use by a computer.
Diopter Adjustment - Adjusts the optical viewfinder's magnification factor to suit the eyesight of the user. Look for a knob or dial next to or beneath the viewfinder's eyepiece. Not all cameras have this feature.
Dithering - A method for simulating many colors or shades of gray with only a few. A limited number of same-colored pixels located close together are seen as a new color.
DPI - Dots per Inch. A measurement value used to describe either the resolution of a display screen or the output resolution of a printer.
DPI - Dots per Inch. A measurement value used to describe either the resolution of a display screen or the output resolution of a printer.
DPOF - Digital Print Order Format. Allows you to embed printing information on your memory card. Select the pictures to be printed and how many prints to make. Some photo printers with card slots will use this info at print time. Mostly used by commercial photo finishers or those Kodak kiosks you find in the mall.
DRAM - Dynamic Random Access Memory. A type of memory that is volatile - it is lost when the power is turned off.
DRAM Buffer - All digicams have a certain amount of fixed memory in them to facilitate image processing before the finished picture is stored to the flash memory card. Cameras that have a burst mode have much larger DRAM buffers, often 32MB or larger. This also makes them more expensive. DSLR - Digital SLR (Single Lens Reflex) camera. Interchangeable lens digital camera. Manufacturers include Canon, Fuji, Kodak, Nikon, Olympus, Pentax and Sigma.
DVD - "Digital Versatile Disc"DVD is DVD-Video recorded on a DVD-R or DVD-RW disc, which contains superior quality video (MPEG-2) and audio. Typically, a DVD can hold more than one hour of video.
Dye Sub - Dye Sublimation is a printing process where the color dyes are thermally transferred to the printing media. Dye sub printers use the CMYK (cyan, magenta, yellow, black) color format and have either three ribbons (cyan, magenta and yellow) or high-end printers have four CMY plus a blacK. The paper is run in and out of the printer four times, once for each color and then a fourth time when a protective overcoat is applied. Dye sub is continuous tone printing; it prints tiny square dots each of which is denser in the center and lighter on the edges. These dots can be varied from almost no dot at all to an almost completely solid dot. The dyes are transparent so different colored dots can be printed on top of each other to form any one of 16-million colors. This is known as the subtractive color process. Dye sub prints rival conventional photographs in both their color gamut and longevity with water and UV resistant qualities.
Dynamic Range - A measurement of the accuracy of an image in color or gray level. More bits of dynamic range results in finer gradations being preserved.
Depth of field. The distance between the nearest and farthest points that appears in acceptably sharp focus in a photograph. Depth of field varies with lens aperture, focal length, and camera-to-subject distance.
Docking station. A small base connected to the computer by a cable. You insert the camera or other device into the docking station to transfer images.
Download. Sending a file from another device to your computer.
E-TTL / E-TTL II - Canon's flash exposure system used on their digital SLRs. To quote Canon: "The “smarter” E-TTL II system captures the subject as a “plane” and ensures that images containing various colors and levels of reflection are captured accurately and optimally. The system compares the ambient light with the reflected pre- flash off the subject reported in all 35 metering zones and selects the areas with a small difference to be weighted for flash exposure calculation. This system also eliminates or under weights areas with large difference recognizing them as an extremely reflective object in the background or as a highly reflective subject, smartly ensuring it by considering the distance information data provided from compatible EF lenses. The system similarly prevents over-exposure when photographers lock focus and recompose the shot by considering the flash output level calculated according to the broader distance."
DVD - "Digital Versatile Disc"DVD is DVD-Video recorded on a DVD-R or DVD-RW disc, which contains superior quality video (MPEG-2) and audio. Typically, a DVD can hold more than one hour of video.
Dye Sub - Dye Sublimation is a printing process where the color dyes are thermally transferred to the printing media. Dye sub printers use the CMYK (cyan, magenta, yellow, black) color format and have either three ribbons (cyan, magenta and yellow) or high-end printers have four CMY plus a blacK. The paper is run in and out of the printer four times, once for each color and then a fourth time when a protective overcoat is applied. Dye sub is continuous tone printing; it prints tiny square dots each of which is denser in the center and lighter on the edges. These dots can be varied from almost no dot at all to an almost completely solid dot. The dyes are transparent so different colored dots can be printed on top of each other to form any one of 16-million colors. This is known as the subtractive color process. Dye sub prints rival conventional photographs in both their color gamut and longevity with water and UV resistant qualities.
Dynamic Range - A measurement of the accuracy of an image in color or gray level. More bits of dynamic range results in finer gradations being preserved.
Depth of field. The distance between the nearest and farthest points that appears in acceptably sharp focus in a photograph. Depth of field varies with lens aperture, focal length, and camera-to-subject distance.
Docking station. A small base connected to the computer by a cable. You insert the camera or other device into the docking station to transfer images.
Download. Sending a file from another device to your computer.
E-TTL / E-TTL II - Canon's flash exposure system used on their digital SLRs. To quote Canon: "The “smarter” E-TTL II system captures the subject as a “plane” and ensures that images containing various colors and levels of reflection are captured accurately and optimally. The system compares the ambient light with the reflected pre- flash off the subject reported in all 35 metering zones and selects the areas with a small difference to be weighted for flash exposure calculation. This system also eliminates or under weights areas with large difference recognizing them as an extremely reflective object in the background or as a highly reflective subject, smartly ensuring it by considering the distance information data provided from compatible EF lenses. The system similarly prevents over-exposure when photographers lock focus and recompose the shot by considering the flash output level calculated according to the broader distance."
EPP - Enhanced Parallel Port - the newer hi-speed, bidirectional printer port on modern computers. Some older digicams and scanners use the EPP port to transfer data.
ERI-JPEG - Extended Range Imaging Technology, a new file format used in Kodak professional digital cameras. This proprietary technology offers an innovative image file format similar to a JPEG, but with the dynamic range and color gamut information of raw DCR camera files. Extended Range Imaging Technology files allow you to easily open, edit, and print JPEG files within your JPEG workflow. Your JPEG files are captured directly in the camera. With ERI, you'll have the extensive editing, color balance, and color compensation capabilities of RAW digital negatives for applying to your JPEG files.
E-TTL - Canon's Evaluative-TTL exposure system that uses a brief pre-flash before the main flash to calculate the exposure index.
EV - Exposure Value, a very complex thing but in the digicam world it usually means the ability to override the auto exposure system to lighten or darken an image. EVF - Electronic ViewFinder, a small color LCD with a magnified lens that functions as an eye level viewfinder. Usually found on video camcorders but they have been showing up on super-zoom digicams where optical viewfinders are impractical. (Canon Pro90, Fuji 2800Z, Olympus C-2100, Nikon Coolpix 5700).
EXIF - EXIF (Exchangeable Image File format) refers to the embedded camera and exposure information that a digital camera puts in the header of the JPG files it creates. Many graphic programs (Photoshop, ThumbsPlus, Qimage Pro, CameraAid) can read and display this information.
Exif Print - Exif Print (Exif 2.2) is a new worldwide printer independent standard. Under Exif 2.2, the digital still camera can record data tags for specific camera settings and functions such as whether the flash was on or off, if the camera was in landscape, portrait or night scene mode, etc. Referencing some or all of this information, an Exif Print compatible application can process digital camera images intelligently based on specific camera settings and the shooting environment.
Exposure compensation. The ability to adjust exposure by one or two stops to lighten or darken the image.
Exposure/focus lock. The ability to point at one part of the scene and hold the shutter button half-way down to lock in exposure and focus settings when you point the camera elsewhere to compose the scene.
Firewire. See IEEE 1394.
Flash card reader. An accessory that attaches to your computer by cable. You insert a flash memory card into the reader to transfer files.
Flash memory card. A card containing chips that store images.
Flash memory. A form of memory using chips instead of magnetic media. The data in the device isn’t lost when the power is turned off.
Flash, fill. Flash used to fill shadows even when there is enough light to otherwise take the photograph.
Flash, ring. -A special circular flash that fits over a lens to take close-up pictures
Flash, slave.- A flash that fires when it senses the light from another flash unit.
FlashPix. -An image format that contains a number of resolutions, each of which is broken into tiles that can be edited and displayed independently.
Floppy drive,-A storage device on almost all computers that accepts 3 ½ or 5 ¼-inch floppy disks.
FPX - FlashPiX - Trade name for a new multi-resolution image file format jointly developed and introduced in June 1996 by Kodak, HP, Microsoft and Live Picture.
Full Bleed - Printing term used when an image or inked area extends to the edge of all four sides of the printed piece. Better known as "borderless" in today's world of inkjet photo printers.
Frame grabber. A device that lets you capture individual frames out of a video camera or off a video tape.
Frame Rate. The number of pictures that can be taken in a given period of time.
Gamma - A measure of the amount of contrast found in an image according to the properties of a gradation curve. High contrast has high gamma and low contrast low gamma.
Exposure compensation. The ability to adjust exposure by one or two stops to lighten or darken the image.
Exposure/focus lock. The ability to point at one part of the scene and hold the shutter button half-way down to lock in exposure and focus settings when you point the camera elsewhere to compose the scene.
Firewire. See IEEE 1394.
Flash card reader. An accessory that attaches to your computer by cable. You insert a flash memory card into the reader to transfer files.
Flash memory card. A card containing chips that store images.
Flash memory. A form of memory using chips instead of magnetic media. The data in the device isn’t lost when the power is turned off.
Flash, fill. Flash used to fill shadows even when there is enough light to otherwise take the photograph.
Flash, ring. -A special circular flash that fits over a lens to take close-up pictures
Flash, slave.- A flash that fires when it senses the light from another flash unit.
FlashPix. -An image format that contains a number of resolutions, each of which is broken into tiles that can be edited and displayed independently.
Floppy drive,-A storage device on almost all computers that accepts 3 ½ or 5 ¼-inch floppy disks.
FPX - FlashPiX - Trade name for a new multi-resolution image file format jointly developed and introduced in June 1996 by Kodak, HP, Microsoft and Live Picture.
Full Bleed - Printing term used when an image or inked area extends to the edge of all four sides of the printed piece. Better known as "borderless" in today's world of inkjet photo printers.
Frame grabber. A device that lets you capture individual frames out of a video camera or off a video tape.
Frame Rate. The number of pictures that can be taken in a given period of time.
Gamma - A measure of the amount of contrast found in an image according to the properties of a gradation curve. High contrast has high gamma and low contrast low gamma.
Gamma Correction - In reference to displaying an image accurately on a computer screen, Gamma correction controls the overall brightness of an image. Images which are not properly corrected can look either bleached out, or too dark.
Gamut - The range of colors that are available in an image or output process. It is generally used in describing the capabilities of a printer to reproduce colors faithfully and vibrantly - i.e. "The xxxxx printer has a wide color gamut."
GIF. -An image file format designed for display of line art on the Web.
Gray market.- Importing camera equipment outside of the normal manufacturer’s distribution channels to take advantage of lower prices elsewhere in the world.
Gigabyte (GB) - A measure of computer memory or disk space consisting of about one thousand million bytes (a thousand megabytes). The actual value is 1,073,741,824 bytes (1024 megabytes). Gradation - A smooth transition between black and white, one color and another, color and no color. Gray Level - The brightness of a pixel. The value associated with a pixel representing it's lightness from black to white. Usually defined as a value from 0 to 255, with 0 being black and 255 being white. Gray Scale - A term used to describe an image containing shades of gray rather than color. Most commonly referred to as a black and white photo
Guide Number - The output power rating of a electronic flash unit.
HAD CCD - Sony's latest CCD imager, HAD = Hole Accumulation Diode
Gamut - The range of colors that are available in an image or output process. It is generally used in describing the capabilities of a printer to reproduce colors faithfully and vibrantly - i.e. "The xxxxx printer has a wide color gamut."
GIF. -An image file format designed for display of line art on the Web.
Gray market.- Importing camera equipment outside of the normal manufacturer’s distribution channels to take advantage of lower prices elsewhere in the world.
Gigabyte (GB) - A measure of computer memory or disk space consisting of about one thousand million bytes (a thousand megabytes). The actual value is 1,073,741,824 bytes (1024 megabytes). Gradation - A smooth transition between black and white, one color and another, color and no color. Gray Level - The brightness of a pixel. The value associated with a pixel representing it's lightness from black to white. Usually defined as a value from 0 to 255, with 0 being black and 255 being white. Gray Scale - A term used to describe an image containing shades of gray rather than color. Most commonly referred to as a black and white photo
Guide Number - The output power rating of a electronic flash unit.
HAD CCD - Sony's latest CCD imager, HAD = Hole Accumulation Diode
Halftone Image - An image reproduced through a special screen made up of dots of various sizes to simulate shades of gray in a photograph. Typically used for newspaper or magazine reproduction of images but it is also how today's inkjet printers work. Halftoning or dithering are the methods used to produce a smooth gradation of color versus distinct bands of color or moirè patterns.
HD - Hard drive (aka HDD), the internal, large-capacity data storage unit in today's PC computers.
HDTV - High Definition Television. New video "standard" that will resolve 1,125 lines in the United States instead of the traditional 525 lines of the NTSC standard. The aspect ratio is 16:9 versus 4:3 of regular TV sets. Histogram - A bar graph analysis tool that can be used to identify contrast and dynamic range of an image. Histograms are found in the more advanced digicams and software programs (graphic editors) used to manipulate digital images. The histogram shows a scale of 0 - 255 (left to right) with 0 being black and 255 being white.
Hot Shoe - A flash connector generally found on the top of the camera that lets you attach a flash unit and trigger it in sync with the shutter. Hologram Laser AF - Sony introduced a new laser-assisted auto focus system on the Cyber-shot DCS-F707 that uses a safe Class 1 laser to paint a grid on the subject that makes the auto focus fast and accurate. Also found on the DSC-F717, F828, V1 and V3 cameras.
Hue - A term used to describe the entire range of colors of the spectrum; hue is the component that determines just what color you are using. In gradients, when you use a color model in which hue is a component, you can create rainbow effects.
IEEE 1394.- A new port on the computer capable of transferring large amounts of data. Currently the fastest available port.
i-TTL - Nikon's new flash exposure system, used on new D70 digital SLR and SB-600 and SB-800 Speedlights.
IEEE 1394.- A new port on the computer capable of transferring large amounts of data. Currently the fastest available port.
i-TTL - Nikon's new flash exposure system, used on new D70 digital SLR and SB-600 and SB-800 Speedlights.
ICC Profile - The International Color Consortium, a group that sets standard guidelines for color management in the imaging world. Most printers, monitors and scanners as well as digital cameras, usually come with a driver disc for Windows and Mac systems that includes ICC profiles for the particular device. Color profiles simply let one piece of hardware or software "know" how another device or image created its colors and how they should be interpreted or reproduced. IEEE-1284 - This is the high-speed bidirectional parallel port specification used on Windows PCs mostly for printers.
IEEE-1394 - Better known as "FireWire" - it's a high-speed input/output bus used by digital video devices, film/flatbed scanners, high-end digital still cameras & PCs. iESP - Olympus' exposure metering system. iLink - Sony's term for IEE-1394 FireWire data port found on their camcorders. Image Processing - Capturing and manipulating images in order to enhance or extract information. Image Resolution - The number of pixels per unit length of image. For example, pixels per inch, pixels per millimeter, or pixels wide.
Image sensor. A solid-state device containing a photosite for each pixel in the image. Each photosite records the brightness of the light that strikes it during an exposure.
Image Stabilization - An optical or digital system for removing or reducing camera movement in telephoto zoom lenses. Usually found only on extremely long focal length lenses such as the 10X lens on Sony Mavicas and Olympus C-2100UZ, E-100RS. Can also be found on Panasonic FZ1/FZ2/FZ10's 12X Leica zoom lens. InfoLITHIUM - Sony's "smart" lithium rechargeable battery pack. It has a chip inside that tells the camera how long (in minutes) it will last at the current discharge rate.
Image sensor. A solid-state device containing a photosite for each pixel in the image. Each photosite records the brightness of the light that strikes it during an exposure.
Image Stabilization - An optical or digital system for removing or reducing camera movement in telephoto zoom lenses. Usually found only on extremely long focal length lenses such as the 10X lens on Sony Mavicas and Olympus C-2100UZ, E-100RS. Can also be found on Panasonic FZ1/FZ2/FZ10's 12X Leica zoom lens. InfoLITHIUM - Sony's "smart" lithium rechargeable battery pack. It has a chip inside that tells the camera how long (in minutes) it will last at the current discharge rate.
Inkjet - A type of printer that sprays dots of ink onto paper to create the image. Modern inkjet printers now have resolutions of up to 2880dpi and create true photo-quality prints. Interlaced - Term used to describe an image sensor that gathers its data by first processing the odd lines and then the even lines. See also "Progressive Scan" for the other (preferred) method. Interpolated - Software programs can enlarge image resolution beyond the actual resolution by adding extra pixels using complex mathematic calculations. See "Resolution" below Intervalometer - Fancy term for Time-Lapse. Capture an image or series of images at preset intervals automatically. Interval Recording - Capturing a series of images at preset intervals. Also called time-lapse.
Infrared. See IrDA. IR - InfraRed (aka IrDA) uses an invisible (to humans) beam of light to either wirelessly control a device or as a method of transferring data from camera to computer (or printer) without cables. Some cameras also employ infrared in the auto focusing system.
Interpolation. In an image interpolation adds extra pixels. It’s done with some zoom lenses.
Inverse square law. The physical law that causes light from a flash to fall off in such a way that as flash to subject distance doubles, the light falls off by a factor of four.
IrDA. -An agreed upon standard that allows data to be transferred between devices using infrared light instead of cables..
ISO.- A number rating indicating the relative sensitivity to light of an image sensor or photographic film. Faster film (higher ISO) is more sensitive to light and requires less exposure than does slower film.
Infrared. See IrDA. IR - InfraRed (aka IrDA) uses an invisible (to humans) beam of light to either wirelessly control a device or as a method of transferring data from camera to computer (or printer) without cables. Some cameras also employ infrared in the auto focusing system.
Interpolation. In an image interpolation adds extra pixels. It’s done with some zoom lenses.
Inverse square law. The physical law that causes light from a flash to fall off in such a way that as flash to subject distance doubles, the light falls off by a factor of four.
IrDA. -An agreed upon standard that allows data to be transferred between devices using infrared light instead of cables..
ISO.- A number rating indicating the relative sensitivity to light of an image sensor or photographic film. Faster film (higher ISO) is more sensitive to light and requires less exposure than does slower film.
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