principles of light the science behind photography
TRANSCRIPT
Principles of LightThe Science Behind Photography
1. White light is made up of equal amounts of red, blue and green light.
1. White light is made up of equal amounts of red, blue and green light.
additive process
subtractive process
1. White light is made up of equal amounts of red, blue and green light.
• Red, Blue and Green
• Cannot be made
• Exist in Nature
• PRIMARY COLORS
RED
GREENBLUE
WHITE
1. White light is made up of equal amounts of red, blue and green light.
RED
GREENBLUE
WHITE
MAGENTA YELLOW
CYAN
1. White light is made up of equal amounts of red, blue and green light.
• Cyan, Magenta, Yellow
• Combine EQUAL amounts of 2 PRIMARY colors
• SECONDARY COLORS
RED
GREENBLUE
WHITE
MAGENTA YELLOW
CYAN
1. White light is made up of equal amounts of red, blue and green light.
• Wavelengths of color are viewed on the spectrum.
• Visible Spectrum = RainbowWater acts like a PRISM to REFRACT or BREAK APART white light into all colors
1. White light is made up of equal amounts of red, blue and green light.
INVISIBLESPECTRUM
Cameras can see
infrared and ultraviolet
but we cannot.
1. White light is made up of equal amounts of red, blue and green light.
VISIBLESPECTRUM
+INVISIBLESPECTRUM
=TOTAL
SPECTRUM
2. Objects get their color from reflected light.
• All colored objects reflect light to some degree.
• White objects reflect all the light that hits them.
• Can only take a photograph when there is a light source.
• No light = No color
2. Objects get their color from reflected light.
2. Objects get their color from reflected light.
Can you change the color of an object by changing the light source?
2. Objects get their color from reflected light.
You can change the color of an object by changing the light source!
3. Black objects absorb all light.
• Black is not a color• It is the absence of color• Black objects absorb ALL the light
that hits them• Inside if cameras, darkroom,
developing tanks are black• WHY?
Can you see this?
3. Black objects absorb all light.
Can a camera see black?
Can black be photographed?
Will the film be exposed?
3. Black objects absorb all light.
Camera cannot see black?
Black cannot be photographed?
The film will not be exposed?
4. Silver, when struck by light, turns black.
• Silver is the main ingredient in film/ photo paper because it is sensitive to light.
• Silverware and jewelry tarnishes.
4. Silver, when struck by light, turns black.
• Film/photo paper has two main layers:• Emulsion• Base• Emulsion – silver particles suspended in a gel
• Base – support for the emulsion; paper or plastic
4. Silver, when struck by light, turns black.
• Emulsion – silver particles suspended in a gel• Base – support for the emulsion; paper or plastic
CURLS TOWARDSTHE EMULSION
EMULSION
BASE
4. Silver, when struck by light, turns black.
CURLS TOWARDSTHE EMULSION
PAPER = SHINY
FILM = LIGHTER
EMULSION
BASE
5. Light travels in a straight path.
• Light travels in wavelengths.
5. Light travels in a straight path.
5. Light travels in a straight path.
• Images are recorded on film upside down and reversed.
• We see the same way.
5. Light travels in a straight path.
5. Light travels in a straight path.
5. Light travels in a straight path.
• Larger lens opening, more light, blurry image
• Smaller lens opening, less light, sharper image
Pupils dilated by eye
doctor?
Squint eyes to see
better?
http://youtu.be/O0PawPSdk28