Aberration
An optical defect in a lens causing it to form an image that is not sharp or that is distorted. This can take the shape of edge distortion or a lack of sharpness.
An optical defect in a lens causing it to form an image that is not sharp or that is distorted. This can take the shape of edge distortion or a lack of sharpness.
Angle of View
The area of a scene that a lens can cover. The focal length of the lens determines the angle of view. A wide-angle (short-focal-length) lens includes more of a scene than a standard (normal-focal-length) lens or telephoto (long-focal-length) lens. Angle of view is basically the angle at which light rays can pass through the lens to produce an image on the film.
The area of a scene that a lens can cover. The focal length of the lens determines the angle of view. A wide-angle (short-focal-length) lens includes more of a scene than a standard (normal-focal-length) lens or telephoto (long-focal-length) lens. Angle of view is basically the angle at which light rays can pass through the lens to produce an image on the film.
Aperture
The aperture is the opening formed by the blades of the iris or diaphragm in the lens, through which light passes to expose the film. Aperture size is usually given in f-numbers, the larger the number, the smaller the opening. Aperture size together with shutter speed determine the amount of light falling on the film (exposure). The aperture is sometimes called the “stop".
Aspherical lensThe aperture is the opening formed by the blades of the iris or diaphragm in the lens, through which light passes to expose the film. Aperture size is usually given in f-numbers, the larger the number, the smaller the opening. Aperture size together with shutter speed determine the amount of light falling on the film (exposure). The aperture is sometimes called the “stop".
A lens with a curved, non-spherical surface. Used to reduce aberrations and achieve a more compact lens size. With a spherical lens, rays traveling from the lens periphery create the image before the ideal focal point and give a blurred image center. With an aspherical lens, even the rays traveling from the lens periphery converge at the ideal focal point, thus producing a sharp image.
Barrel Distortion
Image distortion produced when the position of the camera lens is at its widest angle. Lines you expect to appear perpendicular are not. It is most noticeable when you have a straight edge near the side of the frame, such as when taking a wide angle shot of a building. Barrel distortion causes the edges of an image to look curved or at a skewed angle. Most barrel distortion can be corrected using image editing software.
Image distortion produced when the position of the camera lens is at its widest angle. Lines you expect to appear perpendicular are not. It is most noticeable when you have a straight edge near the side of the frame, such as when taking a wide angle shot of a building. Barrel distortion causes the edges of an image to look curved or at a skewed angle. Most barrel distortion can be corrected using image editing software.
Bracketing
Best explained as the photographer taking numerous photos of the same thing using a variety of different camera settings. Bracketing is great when you are struggling to get a shot with exposure you like and that suits the image generally and helps ensure correct exposure of a photo when lighting in a scene is difficult.
Best explained as the photographer taking numerous photos of the same thing using a variety of different camera settings. Bracketing is great when you are struggling to get a shot with exposure you like and that suits the image generally and helps ensure correct exposure of a photo when lighting in a scene is difficult.
Camera Shake
Caused by even a slight movement of the camera as it records an image. Camera shake is the main cause of blurred images.
Caused by even a slight movement of the camera as it records an image. Camera shake is the main cause of blurred images.
Chromatic aberration
The inability of a lens to bring all light wavelengths (particularly red & blue) into the same plane of focus, thus causing overall blur. Usually found in regular large-aperture telephoto and super-telephoto lenses. Not improved by reducing aperture size. Can be corrected with low dispersion (ED, LD SD) glass.
The inability of a lens to bring all light wavelengths (particularly red & blue) into the same plane of focus, thus causing overall blur. Usually found in regular large-aperture telephoto and super-telephoto lenses. Not improved by reducing aperture size. Can be corrected with low dispersion (ED, LD SD) glass.
CMYK
The four process colors used in printing: cyan, magenta, yellow, and black. CMYK image A four-channel image containing a cyan, magenta, yellow, and black channel. A CMYK image is generally used to print a color separation. When submitting photos to traditional printing presses you will often need to convert to CMYK. The conversion from RGB to CMYK will often cause dramatic changes in your digital image.
The four process colors used in printing: cyan, magenta, yellow, and black. CMYK image A four-channel image containing a cyan, magenta, yellow, and black channel. A CMYK image is generally used to print a color separation. When submitting photos to traditional printing presses you will often need to convert to CMYK. The conversion from RGB to CMYK will often cause dramatic changes in your digital image.
Color temperature - Color of Light
A method of expressing the color content and quality of light and measured in Kelvin (K). “Photographic daylight" has a color temperature of about 5500K. Photographic tungsten lights have color temperatures of 3200K to 3400K depending on their construction.
A method of expressing the color content and quality of light and measured in Kelvin (K). “Photographic daylight" has a color temperature of about 5500K. Photographic tungsten lights have color temperatures of 3200K to 3400K depending on their construction.
Depth of Field
Refers to how much of a photo is in focus when the camera is focused on the main subject. Depth-of-field is controlled by a camera's aperture, in conjunction with the focal length of the lens. Deep (more) depth-of-field means that all or most of the picture is in focus from front to back. Shallow (less) depth-of-field means that a subject is in focus but objects in front and behind it appear out of focus.
Refers to how much of a photo is in focus when the camera is focused on the main subject. Depth-of-field is controlled by a camera's aperture, in conjunction with the focal length of the lens. Deep (more) depth-of-field means that all or most of the picture is in focus from front to back. Shallow (less) depth-of-field means that a subject is in focus but objects in front and behind it appear out of focus.
Digital Zoom
This is a common term for small video cameras and digital cameras. Digital zoom is electronic zoom where the camera interpolates the sensor readings to simulate a zoom.. Many people consider this to be a poorer quality image.
This is a common term for small video cameras and digital cameras. Digital zoom is electronic zoom where the camera interpolates the sensor readings to simulate a zoom.. Many people consider this to be a poorer quality image.
Electronic flash
Designed to provide light where the lighting on the scene is insufficient. Electronic flash requires high voltage, usually obtained through batteries and a voltage-multiplying circuit which discharge a brief, intensive burst. Generally considered to have the same photographic effect as daylight. Modern flash units have multiple TTL exposure control functions and auto focus control.
Designed to provide light where the lighting on the scene is insufficient. Electronic flash requires high voltage, usually obtained through batteries and a voltage-multiplying circuit which discharge a brief, intensive burst. Generally considered to have the same photographic effect as daylight. Modern flash units have multiple TTL exposure control functions and auto focus control.
Exposure Compensation
Increase or decrease the exposure an image from the exposure automatically selected by a camera metering system.
Exposure meter: Built-in digital camera meter that measures the amount of light when framing a photo and determines the best exposure. Matrix (Evaluative), Spot and Center-weighted are the main metering types; some digital cameras have all three.
F-numbers or F-stops
Numbers on the lens aperture ring and the camera's LCD (where applicable) that indicate the size of lens aperture. The lower the number the larger the aperture. As the scale rises, each number is multiplied by a factor of 1.4. Standard numbers are 1.0,1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc., each change resulting in a doubling or halving of the amount of light transmitted by the lens to the film. The actual value is represents a relationship between the focal length of the lens. f numbers are calculated by dividing the focal length of the lens by the effective diameter of the aperture.
Numbers on the lens aperture ring and the camera's LCD (where applicable) that indicate the size of lens aperture. The lower the number the larger the aperture. As the scale rises, each number is multiplied by a factor of 1.4. Standard numbers are 1.0,1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc., each change resulting in a doubling or halving of the amount of light transmitted by the lens to the film. The actual value is represents a relationship between the focal length of the lens. f numbers are calculated by dividing the focal length of the lens by the effective diameter of the aperture.
Film Speed/ISO/ASA
ISO stands for International Standards Organization and numbers such as ISO 100 or ISO 400 etc. Film was always manufactured to be at a certain ASA. Digital cameras give you the ability adjust your sensitivyt to light or ISO. The higher the number, the more sensitive or faster the film. Basically, the slower the film (low ISO No.) the sharper and clearer the photograph. Grainy effects can be achieved with fast films (high ISO No.).
ISO stands for International Standards Organization and numbers such as ISO 100 or ISO 400 etc. Film was always manufactured to be at a certain ASA. Digital cameras give you the ability adjust your sensitivyt to light or ISO. The higher the number, the more sensitive or faster the film. Basically, the slower the film (low ISO No.) the sharper and clearer the photograph. Grainy effects can be achieved with fast films (high ISO No.).
In a digital camera a higher ISO setting will mean the sensor is more sensitive to light and can allow faster shutter speeds. The negative side to this is that higher ISOs sometimes produce images that are noisy with digital grain.
Focal Length
The distance from the film to the optical center of the lens when the lens is focused on infinity. Focal length on most adjustable cameras is marked in millimeters on the lens mount. On 35mm-format cameras, lenses with a focal length of 50mm are called normal or standard lenses. Lenses of 35mm or less are called wide angle lenses and lenses of 85mm or more are called telephoto lenses. Lenses which allow varying focal lengths without changing focus are called zoom lenses.
The distance from the film to the optical center of the lens when the lens is focused on infinity. Focal length on most adjustable cameras is marked in millimeters on the lens mount. On 35mm-format cameras, lenses with a focal length of 50mm are called normal or standard lenses. Lenses of 35mm or less are called wide angle lenses and lenses of 85mm or more are called telephoto lenses. Lenses which allow varying focal lengths without changing focus are called zoom lenses.
Focal Plane Shutter
A focal plane shutter exposes the image by moving two light-blocking curtains across the front of the image sensor. The first curtain slides open to begin the exposure, then the second curtain slide closed to terminate the exposure. In order to expose the picture from a flash, both curtains must be open at the time the flash is fired.
A focal plane shutter exposes the image by moving two light-blocking curtains across the front of the image sensor. The first curtain slides open to begin the exposure, then the second curtain slide closed to terminate the exposure. In order to expose the picture from a flash, both curtains must be open at the time the flash is fired.
High Contrast
A wide range of density in a print or negative.
A wide range of density in a print or negative.
Highlights
The brightest areas of a subject and the corresponding areas in a negative, a print, or a slide.
Lens
One or more pieces of optical glass or similar material designed to collect and transfer rays of light to form a sharp image on film, paper or a projection screen. In practical photography, compound lenses made of a number of elements of different types of glass are used. This enables the manufacturer to correct most of the faults (aberrations) found in simple lenses and provide images that are sharp across the whole picture.
One or more pieces of optical glass or similar material designed to collect and transfer rays of light to form a sharp image on film, paper or a projection screen. In practical photography, compound lenses made of a number of elements of different types of glass are used. This enables the manufacturer to correct most of the faults (aberrations) found in simple lenses and provide images that are sharp across the whole picture.
Lens Speed
The largest aperture(smallest F-stop) at which a lens can be set. Fast lenses transmit more light and have larger openings than slow lenses. Determined by the maximum aperture in relation to focal length. Lens speed is relative: a 400 mm lens with a maximum aperture of F/3.5 is considered extremely fast, while a 28mm F/3.5 lens is considered to be quite slow.
The largest aperture(smallest F-stop) at which a lens can be set. Fast lenses transmit more light and have larger openings than slow lenses. Determined by the maximum aperture in relation to focal length. Lens speed is relative: a 400 mm lens with a maximum aperture of F/3.5 is considered extremely fast, while a 28mm F/3.5 lens is considered to be quite slow.
Optical Zoom
A true zoom. The focal length of the lens extends and retracts so an image is magnified by the lens itself. Whatever the focal length of the lens, image resolution stays the same. Optical zooms produce the best photo quality.
A true zoom. The focal length of the lens extends and retracts so an image is magnified by the lens itself. Whatever the focal length of the lens, image resolution stays the same. Optical zooms produce the best photo quality.
Overexposure:
Improper exposure causing an image to look too light. There is a loss of detail in bright areas.
Improper exposure causing an image to look too light. There is a loss of detail in bright areas.
Panning
This refers to following a subject with your camera. If you are photographing a runner you would want to follow the runner with the camera. Done correctly, your subject will be in focus and the background will show motion. This adds motion to a photograph.
This refers to following a subject with your camera. If you are photographing a runner you would want to follow the runner with the camera. Done correctly, your subject will be in focus and the background will show motion. This adds motion to a photograph.
Saturation:
The intensity, or vividness, of a color. Increasing saturation makes colors in photos look richer. The amount of saturation can be adjusted in some cameras. It can also be increased or decreased with image editing software.
The intensity, or vividness, of a color. Increasing saturation makes colors in photos look richer. The amount of saturation can be adjusted in some cameras. It can also be increased or decreased with image editing software.
Shutter Speed
The shutter speed is the length of time that the light capture medium is open to the light. 1/30 is 1/30 of a second. Try to keep your shutter speed 1/90 - 1/125 or faster to avoid camera blur. Anything less than 1/60 and you will need to either use a tripod or be very aware of your camera movement. It all depends upon you. For some, 1/60 may be too slow a shutter speed while others can work at 1/25th. Also note that the longer the focal length, telephoto vs wide angle lens, the more camera movement will affect image sharpness.
Underexposure
A condition in which too little light reaches the film or camera sensor. In general digital handles underexposure better than negative film. Underexposed film will producing a thin negative, a dark slide, or a muddy-looking print.
A condition in which too little light reaches the film or camera sensor. In general digital handles underexposure better than negative film. Underexposed film will producing a thin negative, a dark slide, or a muddy-looking print.
Unipod or Monopod
A one-legged support used to hold the camera steady.
A one-legged support used to hold the camera steady.
Vignetting
A fall-off in brightness at the edges of an image, slide, or print. This can be caused by poor lens design, using a incorrect lens hood, or attaching too many filters to the front of the lens.
A fall-off in brightness at the edges of an image, slide, or print. This can be caused by poor lens design, using a incorrect lens hood, or attaching too many filters to the front of the lens.
Wide-Angle Lens
A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.
A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.
Zoom Lens
A lens in which you adjust the focal length over a wide range. In effect, this gives you lenses of many focal lengths.
A lens in which you adjust the focal length over a wide range. In effect, this gives you lenses of many focal lengths.
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