Term
five digital SLR camera controls |
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Definition
- aperture
- shutter speed
- film-speed (light meter) ISO
- focus
- white balance
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Term
four variables of exposure |
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Definition
- Light source
- Aperture (f-stop)
i. Determines amt of light
ii. Light
iii. Depth-of-field
3. Shutter speed
i. How long shutter stays open
ii. time
iii. motion
4. film speed (ISO)
i. Film sensitivity to light |
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Term
two types of light meters |
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Definition
- incident (additive)
- reflective
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Term
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Definition
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- failure of the meter to know that it’s white instead of gray or black instead of gray
- When the light meter fails to correctly read values because the meter tries to read 18% gray – 18% gray on meter but subject isn’t
i. Putting indicator in the middle assures that it’s going to be gray |
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Term
what does 18% gray represent? |
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Definition
the average light reflected from the average subject. |
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Term
examples of substitution meter readings |
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Definition
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- Using something with the 18% gray value – like an 18% gray card, shadow, shirt, etc – and adjusting your settings
- Then using those settings to take a picture of something else with the same lighting in the same setting
- Meter skin tone which on an average human Caucasian is 18% gray.
i. Didn’t include backlight
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- Use shadows that are about the same value
- Look at shadows, averages
- With the substitution method, you replace an object within the scene with an object, such as a gray card.
then take a reflected-light meter reading from this object. determining exposure are not possible. may be caused by excessive distance between the light meter and the scene, barriers in front of the scene, or the size of the scene makes it impossible to get an accurate light meter reading. used in studio situations where objects may be too small to obtain an accurate light meter reading.
i. You
ii. You use this method when the other methods of
1. Such situations
iii. The substitution method is often
1. Take the light meter reading from the substituted item under similar lighting conditions that exist in the scene. scene is in bright sunlight, the substituted object must also be in bright sunlight.
Likewise, a scene in shade requires a substitute light meter reading in shade
2. When the |
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Term
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Definition
1. theory of mixing light primary colors by adding red, green, and blue to produce white light
a. Based on the principle that all colors of light can be mixed optically by combining in different proportions the primary colors of the spectrum: red, green, and blue
2. All colors of light can be mixed optimally by combining them in different proportions
3. RGB
4. Two primary colors can be mixed to make many colors
ii. Primary
1. Red, green, blue
iii. Secondary
1. Cyan, magenta, yellow
iv. Technology
1. Used with computer monitors
2. CRTs—color television and computer monitors—are a common and significant example of additive color. |
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Term
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Definition
1. theory of mixing light primary colors by subtracting red, green, and blue from white light to produce black by absorbing all wavelengths
a. Operates by removing certain colors from white light while allowing others to pass
b. When white light is passed through one of the subtractive colored filters it transmits two of the primaries and absorbs (subtracts) the other
i. Individually, each subtractive filter transmits 2/3 of the spectrum while blocking 1/3 of it.
2. Removes certain colors from white light
3. CMYK
4. When white light passed through sub color filter, transmits 2 primaries and absorbs/subtracts the other
ii. Primary
1. Magenta, yellow, cyan
iii. Secondary
1. Red, green blue
iv. Technology
1. Printing systems produce color by varying amounts of pigments which absorb light energy, and are subtractive color systems. |
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Term
(2x) mathematical relationship between apertures, shutters, and ISO |
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Definition
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- 1 f-stop (more) = 2 x L (light)
- 1 f-stop (less) = ½ L (light)
- Change of one f-stop – change of 1 shutter speed
i. F11 less light more time
ii. F5.6 more light less time
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- F/stops are a mathematical relationship of the focal length of a lens and the size of the lens opening or aperture.
- The size of the lens opening (aperture) decreases with each larger f/stop number
i. Examples:
1. f/2 is 2x as large as f/2.8
2. f/8 is 2x as large as f/11
3. f/2 is 1/2x as large as f/1.4
4. f/8 is 1/2x as large as f/5.6
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- 1/stop Difference in exposure: from a given initial exposure setting, any change in settings which is a change of 1/2X or 2X as much exposure.
i. The increment between the each whole step of f/stops is called"1/stop"
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- Changing shutter speed one increment is a 1/stop change.
i. Example: changing from 1/30 sec. to 1/60 sec. (1/2X), or changing 1/500 sec. to 1/250 sec. (2X) are both 1/stop changes.
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- Changing f/stops one increment is a 1/stop change.
i. Example: changing f/4 to f/5.6 (1/2X), or f/11 to f/8 (2X) are both 1/stop changes.
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- The ISO number is the "film speed."
- The relationship between the aperture and shutter is known as reciprocity.
i. Reciprocity gives the photographer control over the depth of field of the image, which controls the area of the image that remains in focus.
ii. This is the easiest way to control what part of the image you want the viewer to pay attention to.
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- There is a definite mathematical relationship in film speed ratings:
i. ISO 200 film is exactly twice as sensitive as ISO 100.
ii. Therefore, 100 speed film requires twice as much light for proper exposure as 200 speed; 200 requires twice as much light as 400; 400 requires twice as much light as 800, etc.
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- The f/stop is the relationship between the diameter of the lens opening and the focal length of the lens.
i. This relationship is usually engraved on the lens as a reciprocal. If the diameter of the lens is one-half the focal length of the lens, the f/stop would be indicated as “f/2.”
ii. There is a definite mathematical relationship between the f/stops indicated on a lens.
1. This is based on a logarithmic scale.
2. Some standard lens apertures are f/2, f/2.8. f/4, f/5.6, f/8, f/11, f/16, f/22, and so forth through the logarithmic scale.
a. A higher number indicates a smaller aperture and a smaller number indicates a larger aperture
b. f/2 lets in twice as much light as f/2.8; f/2.8 lets in twice as much as f/4; f/4 twice as much as f/5.6; f/5.6 twice as much as f/8; f/8 twice as much as f/11, etc.
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- The length of time to which the film is exposed to light is controlled by the shutter-speed.
i. The shutter is the device which opens and closes to allow light to enter the camera or to prevent light from entering.
ii. Shutter speeds are indicated in fractions of a second and are indicated on the camera as reciprocals.
1. A shutter speed marked as “500″ on the shutter speed indicator means 1/500 of a second.
2. There is a two-to-one mathematical relationship between shutter speeds.
a. The most common speeds are 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, and 1/2000.
b. Each of these allows light to strike the film for one-half the time of the previous speed, respectively.
c. Some lower-priced cameras have only one shutter speed which cannot be adjusted.
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- If the exposure is too dark, for example, you can choose a larger aperture (lower f-number), a slower (smaller) shutter speed, or a higher ISO to make it brighter.
- A one stop change in shutter speed means a doubling or halving of the speed. One stop in aperture means a doubling or halving of the area of the opening, which means a factor of the square root of 2 (~1.4) in aperture diameter. One stop in ISO is a doubling or halving of the ISO number.
i. A smaller aperture lets in less light so it requires a slower shutter speed to get a good exposure. it also increases the depth of field so more things are in focus (i.e.- foreground middleground and background are in focus)
ii. A larger aperture lets in a lot of light so you need to use a faster shutter speed. it also limits depth of field so you can have one thing in focus and the foreground and background will be blurry.
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- F22 – less light, more time; f2- more light, less time, little depth-of-field
- ISO:
i. 25, 50 – slow – fast speed film
ii. 100, 200 – medium – fast speed film
iii. 400, 800, 1600, 3200 – fast speed film
1. 200 to 100 = -1 f-stop (1/2)
2. 200 to 400 = + 1 f-stop (2x) |
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Term
how to find equivalent exposures at different settings from a given example |
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Definition
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- If you increase the size of your aperture opening, to get an equivalent exposure, you must increase your shutter speed the same number of increments as you did the aperture
- Ex) increase aperture size by 1 f-stop increase shutter speed 1 increment
- Ex) f11 @ 1/125 open aperture to f8, shutter speed for equivalent exposure is 1/250
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Term
seuqence of full f-stops and their relationship to exposure, light and depth-of-field |
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Definition
-
- Numbers
1. F1.4
2. F2
3. F2.8
4. F4
5. F5.6
6. F8
7. F11
8. F16
9. F22
10. F32
a. These numbers also represent fractions – the ratio of the diameter of the aperture to the focal length of the lens
b. Because these f-stops are fractions, the larger numbers represent smaller lens openings and the smaller numbers represent larger lens openings
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- F-stop – indicates the size of the aperture, or lens opening
i. This affects the amount of exposure/light let into the lens
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- Relationship to depth of field
i. The smaller the aperture is, the more it constricts light that passes through it and the more it focuses and increases the depth of field
ii. Lower it is the less sharp the image
iii. Depth of field - the area in front of and behind the subject in acceptable focus
iv. Smaller apertures (but larger numbers on the lens - remember, it’s a reciprocal) increase depth-of-field, while larger apertures (but smaller numbers on the lens) decrease the area of acceptable sharpness
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- If aperture is moved one full f-stop, 2 to 2.8 it increases amount of light,
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Term
sequence of full shutter speeds and their relationship to exposure/light |
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Definition
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- If moved from 1/8 to ¼ affects exposure by letting more light in
- Moved from 1/8 to 1/5 decreases amount of light by a half
CCD Shutter speed:
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Normal
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1/100
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1/250
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1/500
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1/1,000
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1/2,000
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1/4,000
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1/8,000
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Corresponding f-stop (or T-stop):
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16
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11
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8
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5.6
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4.0
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2.8
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2.0
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1.4
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- Each time the shutter speed is doubled the lens must be opened up one f-stop to provide the same net exposure
i. The increased shutter speed cuts the exposure time in half, but opening the iris one f-stop lets twice as much light through the lens to compensate.
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- The shutter speed sequence is 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000 where 30 means 1/30th of a second, same for the rest.
i. If the exposure is too dark, for example, you can choose a larger aperture (lower f-number), a slower (smaller) shutter speed, or a higher ISO to make it brighter.
ii. A smaller aperture lets in less light so it requires a slower shutter speed to get a good exposure. it also increases the depth of field so more things are in focus (i.e.- foreground middleground and background are in focus)
iii. A larger aperture lets in a lot of light so you need to use a faster shutter speed. it also limits depth of field so you can have one thing in focus and the foreground and background will be blurry.
iv. Each shutter setting is approximately double the preceding one. |
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Term
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Definition
- hue
- light-dark
- cold-warm
- compliments
- simultaneous
- saturation
- extension
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Term
depth-of-field (KNOW EXACTLY) |
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Definition
the area in front of and behind the subject in acceptable focus |
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Term
how the resolution of digital prints is determined |
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Definition
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- Formula – image size (in pixels) on one dimension/desired output ppi = maximum output (in inches) on same dimension – done for height and width
i. Tells us print size we can expect to get from file size
ii. Gives optimum
Other things affect it |
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Term
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Definition
i. a tool in Photoshop and other image editing programs which can move and stretch the brightness levels of an image histogram. It has the power to adjust brightness, contrast, and tonal range by specifying the location of complete black, complete white, and midtones in a histogram.
ii. It has the power to adjust brightness, contrast, and tonal range by specifying the location of complete black, complete white, and midtones in a histogram allows for individual adjustment of the highlights, midtones, and shadows. |
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Term
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Definition
i. this tool can take input tones and selectively stretch or compress them. Unlike levels however, which only has black, white and midpoint control, a tonal curve is controlled using any number of anchor points (small squares below, up to a total of 16). The result of a given curve can be visualized by following a test input tone up to the curve, then over to its resulting output tone. A diagonal line through the center will therefore leave tones unchanged. |
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Term
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Definition
i. lightening area of an image |
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Term
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Definition
i. darkening area of an image |
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Term
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Definition
i. brightness – the pixel value in an electron image that represents its lightness value from black to white
1. ranges from 0 (black) to 255 (white)
ii. contrast – the differences in density (values from black to white) or apparent brightness between adjacent tonal areas of a negative or print image
iii. way to adjust the tones of an image
1. box with two sliders, one for brightness and one for contrast |
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Term
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Definition
i. Vertical bar graph displaying the distribution of the tonal values of the pixels in an image. Used to identify contrast and dynamic range in photo-editing programs
ii. the x-axis represents the tonal value of the pixels (0-255)
iii. the y-axis represents the number of pixels having that tonal value
iv. Peaks and valleys of it represent the number of pixels containing those tones.
v. an image with full tonal range will have some tones in every part of it |
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Term
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Definition
i. Control in Photoshop
ii. Under adjustments
1. Color balance |
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Term
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Definition
the capability of a film to reproduce colors as they are perceived, notwithstanding differences in light sources; a property of color film differences in light sources; a property of color film that specifies under what lighting conditions the film will reproduce colors as perceived |
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Term
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Definition
concentration of hue. The degree to which a color is undiluted by white light. |
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Term
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Definition
i. set of images that show the effects of various color adjustments on the images you are adjusting
1. Test to determine the correct color balance of a photograph
2. Image -> adjustments -> variations |
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Term
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Definition
the property of light determined by the wave-lengths of electromagnetic energy of which it is composed; the color characteristic; chroma |
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Term
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Definition
i. the occurrence of color dots or specks where there should be none.
ii. Any undesirable flecks of random color in a portion of an image that should consist of smooth color.
1. It is somewhat similar to the "snowy" appearance of a bad TV signal.
2. Digital images shot in low light or with a high ISO setting often exhibit this undesirable noise.
3. In a way, noise is the digital equivalent of film grain, but noise is generally undesirable, while grain can be desirable.
a. In fact, some digital photographers will curse noise one minute, and the next they may try to create film grain in digital photos for an artistic effect. |
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Term
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Definition
i. Signal-to-noise ratio - The ratio of the usable signal to unusable noise in any signal. In imaging, this represents the quality of the scan.
ii. An image, or picture
iii. literally is light energy
iv. Determines how clear and sharp and image is
v. Higher – more noise
vi. To make better in low light, increase ISO because there’s less light
1. Introduced? |
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Term
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Definition
i. Amount of contrast applied to an image; midtones and how they’re adjusted to affect the desired contrast of the image.
ii. relative brightness of a middle value in an image
iii. adjustments to it lighten or darken the middle tones of the image without changing the shadows and highlights
iv. can range from 0.10 to 9.99
v. if you drag the middle slider to the left, or increase its number, you will lighten middle tones; if you move the slider to the right, you will darken them and decrease the gamma number |
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Term
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Definition
i. a color
1. Ex) red, blue
2. Light transmitted/reflected to eyes
ii. Local color – actual color of an object
1. When we look through a viewfinder, we think in terms of local color |
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Term
light-dark (color contrast) |
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Definition
i. Relates to value
ii. Every hue has a value
1. Every hue has a ___ness or a ___ness
iii. Don’t just look at hue, but look at value relationships of colors |
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Term
cold-warm (color contrast) |
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Definition
i. Warm colors – yellow, orange, red
ii. Cool – green, blue, indigo, violet
iii. Why?
1. Sunlight, fire, temperature, when stove it hot it’s red
2. Learn to associate colors with temperatures |
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Term
compliments (color contrast) |
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Definition
i. Complimentary colors – colors that are opposite each other on the color wheel
1. Subtractive
a. Cyan - red
b. Magenta - Green
c. Yellow - Blue
2. additive
a. green - magenta
b. blue - yellow
c. red - cyan |
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Term
simultaneous (color contrast) |
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Definition
i. If I have this relationship, it means that I have hues that are the same value.
ii. When you have this and the colors are close on the color wheel and put together and have the same value, they act like complementary colors |
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Term
saturation (color contrast) |
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Definition
i. Know from adjustments -> hue saturation in Photoshop
ii. Allows us to adjust hues or to affect the saturation – adding more color; making it more intense |
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Term
extension (color contrast) |
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Definition
i. ________ into the amount of any color
ii. Balance
iii. ________ creates an isolated effect
iv. Making color dominate
v. Proportion of one color to another color
vi. What creates it with color theory?
1. Amount
2. Proportion of one color in relation to another
a. What determines?
i. The hue
ii. Red green
iii. We can use extension to create isolated color
iv. Place emphasis on something |
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Term
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Definition
- closure
- proximity
- continuity
- similarity
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Term
What makes gestalt art different from any other art? |
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Definition
Gestalt – whole greater than sum of parts; image as whole has more value than subject matter |
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Term
What is the average shutter speed for human movement |
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Definition
- 1/60 of a sec
- Depends on speed, light, image sensor rating, and camera technique
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Term
how do you overcome meter failure using substitution meter readings? |
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Definition
What if you can't get close enough to meter the subject? Use substitute metering. Meter something the same tone as the subject and in the same light as the subject |
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Term
how does 18% gray create an average exposure? |
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Definition
i. Reflected-light meters are designed to indicate exposures that will record an average light reflectance as a middle tone of gray
1. The industry standard for this average light level is 18 % reflectance
2. This means that an objects that reflects 18 percent of the light falling on it would be seen as average by a reflected-light meter
3. The exposures indicated by the meter would record that object as a middle tone or gray |
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Term
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Definition
i. gives the photographer control over the depth of field of the image, which controls the area of the image that remains in focus.
ii. This is the easiest way to control what part of the image you want the viewer to pay attention to. |
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Term
control outcome of aperture |
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Definition
i. lets light in; it’s a hole, opening into the lens of the camera
ii. Covered by glass, protected
iii. F-stop – number that tells you how big the whole is
1. Tells you how large the aperture is
2. Critically important to exposure
3. When hole is larger let in more light and number is smaller
4. When hole is smaller let in less light and number is larger |
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Term
control outcomes of shutter speed |
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Definition
i. How fast or slow the shutter opens depends on how much light enters the camera
1. Slower shutter speeds = more light in = higher exposure
2. Faster shutter speed = less light in = lower exposure |
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Term
control outcomes of Film speed (light meter) ISO |
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Definition
i. What determines how much light there is in a given situation – light meter
ii. Film speed indicates how long it takes to be exposed
1. The light sensitivity of the film
Some film take less |
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Term
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Definition
i. Focus lens to selectively choose what we want to be in focus
ii. Determines not only what we’re highlighting but also relates to depth of field
1. Depth-of-field –choose focus on certain plane and space and that focus affects depth of field
a. Depth-of-field - the area in front of and behind the subject in acceptable focus |
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Term
control outcome of white balance |
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Definition
i. Deals with the color temperature and light
ii. it refers to the ability to adjust colors based on white as a reference color to give as true a white as possible; in the process, all the other colors are also corrected. |
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Term
incident (additive) light meter |
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Definition
i. a device designed to measure the intensity of light falling upon or striking a subject
ii. Small unit that is kind of a box shape
iii. Have a hemispherical white dome that is covering the light sensitive diode beneath it
iv. Have a number of numbers and dials you set in order to adjust the ISO and to read the actual light that’s in any given situation
v. Have light source.
1. The light shines down on our subject.
2. We hold the light meter pointed toward the camera.
3. We’re reading the actual light that’s falling on the subject – light read by light meter.
4. The light meter takes the total quantity of light and averages it to 18% gray.
5. Then we take settings from light meter and it tells you the f-stop and shutter speed and all the equivalents you need to use on the camera
a. Accurate and easy
b. If you use specialty lens or have filter on lens light meter isn’t aware off, you’ll have to make adjustments on your own – only reason to have problems
c. Need to be mobile
vi. Read the intensity of light reaching the scene from all sources
vii. Designed to measure the relatively brighter intensity of light sources
viii. designed to measure light falling on the subject
1. to measure, the meter is placed on the subject area, and its light-sensitive cell is pointed in the direction of the camera
2. the diffuser bulb or panel must be used if the meter requires it
3. light falling on the subject then will fall on the photosensitive cell, and the needle in indicate its intensity
a. from this reading a set of equivalent exposures is easily determined
ix. use of this meter assume that the scene has an average contrast range and the suggested exposure setting will yield correct shadows, midtones, and highlights |
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Term
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Definition
i. a light-measuring device designed to respond to the intensity of light reflected from a surface or subject and to compute proper exposure
ii. Meter in your camera in the pentoprism (on top) that read the light coming through the lens being up reflected by the mirror to the light sensitive diodes there and determines how much light will be let into the camera
1. Works different from ambient meter
a. Subject is standing in front of very white wall
i. The light is coming down, hitting subject, and bouncing of subject, wall, ground and hitting back to the camera
ii. Now we are no longer actually reading the actual light hitting the subject
1. The light reflected from the average subject
2. There will be more light reflected than average
iii. Read the intensity of light being reflected form the various objects in the scene
iv. Designed to measure the much lower intensities of reflected light
v. Designed to measure light reflected from the subject
1. To measure this type of light, the meter is placed between the camera and the subject and its light-sensitive cell is pointed in the direction of the light
2. A diffuser bulb or panel mustn’t be used when measuring this type of light
a. Light reflected from the subject toward the camera then will fall on the photosensitive cell and the needle will indicate its intensity
vi. The meter may be used to measure these various intensities separately by brining it close to the various objects in the scene
vii. Major advantaged is that it can be used to measure the light reflected from different areas of the scene and to evaluate the different effects these areas will have upon the negative image |
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Term
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Definition
one of the gestalt principles
nearly complete familiar lines and shapes are more readily seen as complete (closed) than incomplete |
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Term
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Definition
one of the gestalt principles
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-
the closer to or more visual elements are, the greater is the probability that they will be seen as a group or pattern
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Term
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Definition
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visual elements that require the fewest number of interruptions will be grouped to form continuous straight or curved lines
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Term
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Definition
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visual elements that are similar (in size, color, texture, shape, position, proximity, meaning) tend to be seen as related
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Term
gestalt laws of organization |
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Definition
one attempt to formulate a set of principles that seem to describe the way we segregate and group visual elements into patterns of units |
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Term
equivalent exposure chart |
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Definition
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