Films:
Black and White – You will be using T-MAX 400
• Negative
Panchromatic – film that is sensitive to all the wavelengths in the visible spectrum.
Orthochromatic – film that is sensitive to blue and green light but not red light.
Film’s make-up:
[ Scratch resistant top coat
[ Light sensitive emulsion
[ Film base
[ Anti-halation coating
Cross section of film emulsion.
The Latent Image is formed when light acts on a photographic emulsion. This image is invisible until the emulsion is developed using photographic developers, such as D76
ISO/ASA
To calculate the ASA number multiply the ISO by one.
The ASA number is a measurement of the film's sensitivity to light, often referred to as its “speed”.
1. The higher the number the more sensitive to light.
2. As the number doubles, the films sensitivity to light doubles
3. Lower ISO films have less grain structure.
4. Higher ISO films have more grain structure.
Other film characteristics:
• Grain
• Contrast
• Expiration Date
• Storage Temperature
Exposure
Exposure is the amount of light that strikes the photo material -- film or printing paper.
Four things effect the exposure:
1. The film ISO
2. The amount of available or existing light
3. The time the light strikes the film
4. The intensity of light that strikes the film in that time.
Exposure = Time x Intensity
Shutter Speed
Time is controlled by the shutter. The time the shutter remains open lets light strike the film is controlled by the shutter speed. Typical shutter speeds:
1/1000 1/500 1/250 1/125 1/60 1/30 1/15 1/8 1/4 1/2 1 B
fast shutter speed = less light slower shutter speed = more light
1. As the shutter speed is increased (a faster shutter speed) less light strikes the film.
reducing the exposure
• Increase the shutter speed by a standard “unit” reduces the light striking the film by half.
2. As the shutter speed is reduced (slower shutter speed) more light strikes the film,
increasing exposure.
• Reducing the shutter speed by a standard “unit” doubles the light striking the film.
Shutter speed controls the illusion of motion
1. fast shutter speeds stop action
2. slow shutter speeds blur motion
3. panning freezes subject and blurs background
F-stops and Apertures
The intensity of light that passes through the lens and strikes the film is controlled by the
Aperture. The aperture is expressed in f-stops. Typical f-stops are:
f 1.4 f2 f2.8 f4 f5.6 f8 f11 f16 f22 f32 f64
< ---- more light less light ---->
• A large aperture, such as f2, lets in more light than a smaller aperture such as f16
• Each time the aperture decreases to the next smaller f-stop the amount of light it passes is cut in half.
• As the aperture increases to the next bigger f-stop the amount of light it passes
doubles.
• Different f-numbers provide different depth-of-fields.
How to determine the correct exposure
1. Film instructions
2. The sunny f16 Rule = In full sun set the camera aperture at f16 and the shutter to the speed of the ASA/ISO you are shooting.
3. Light meter
• Only a guide - it is only as accurate as the person using of it
• Light meters interpret (some) colors and tones as medium gray (18%)
• Never point your light meter toward the sun!!!
Camera Light meters
• Battery
• One shutter speed may work without battery
• Always have extra!
• Preset (No light meter)
• Manual
• Semi-automatic
• aperture preferred
• shutter preferred
• Fully automatic
• Programmable
• Displaying exposures - needle match Vs centering Vs lights
Bracketing
Taking several different exposures of the same scene at different exposure settings, some greater than and some less than the setting indicted by the meter, to ensure a well exposed photograph.
SUNNY 16 RULE
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