Transcript aperture at f/16

Photography Lesson 1
The Camera
What is Photography ?
• Photo- Light
• Graph- Drawing
• It means Light Drawing. ... It literally
means "To write with light.“
• A Camera is one of the tools you will use
to capture this light.
Shutter / Aperture / ISO
• Taking a properly exposed photograph
requires a cooperation between a
camera’s shutter, aperture, and film (ISO)
• the shutter and aperture adjust the amount
of light that reaches the film
• Essentially the shutter speed, aperture,
and ISO number are variables in a photo
equation
Film / ISO
• Standard film you’ve probably seen before is most likely
35mm negative film
• Film also comes in a positive form, it is called Slide Film
• Film Speed (ISO 100, 200, and so on) describes a film’s
sensitivity to light. The higher the number the more
sensitive (“faster”) the film, and the less light it needs for
the picture to be neither too light nor too dark.
• A setting of 100 to 200 is good for learning to shoot
outdoors in sunny conditions. In dimmer light, speeds of
400 or higher are required.
• Digital cameras don’t use film, they have a digital light
chip, they also have a built in, usually adjustable ISO
setting.
The Shutter
• The Shutter-speed controls the length of
time that the shutter remains open.
• A Shorter time decreases the likelihood
that a moving object will appear blurred
• A longer shutter speed will let in more
light, but often blur your picture
Shutter Speed
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The shutter controls the amount of
light that reaches the film by
length of time it remains open.
Doubling the amount of time the
shutter is open is called a “Stop” –
it gives twice as much light.
Shutter Speed is measured in
fractions.
Your camera usually denotes the
shutter speed by displaying the
denominator only.
1/1 = 1 sec
½ = one half of 1 second, it may
be labeled “2”
1/250 = one 250th of a second, it
may be labeled “250”
Don’t confuse 2, meaning 2
seconds, with 2 meaning ½
second; 4 meaning 4 seconds,
with 4, meaning ¼ second, and so
on.
Leaf / Between-the-lens Shutter
• There are 2 main kinds of
shutters available to cameras.
• A leaf or between-the-lens
shutter is generally located
inside the lens itself. All view
cameras and most point-andshoot cameras use leaf
shutters.
• A flash can be used at any
speed.
• Lenses will cost more.
• Actual shutter time will vary
from lens to lens
Focal-Plane Shutter
• The other shutter is a focalplane shutter.
• A focal-plane shutter is built
into the camera body and is
located directly in front of the
film.
• The shutter consists of two
overlapping curtains.
• Lenses are less expensive.
• Shutter speeds can be higher
• Can’t use a flash when both
curtains are moving. If the
shutter speed is too fast, a
sliver of flash appears.
Motion Blur
Aperture / Opening
• The aperture (size of lens opening) controls the
brightness of the light that reaches the film.
• The aperture adjusts the size of the lens
opening – the diaphragm. The smaller the
aperture opening the greater the depth of field
• The Depth of Field is the part of the image near
to far that will be sharp and in focus.
• The aperture is more or less like the
pupil in your eye
• The size of an aperture is measured
by it’s f-number or f-stop
• The lower the f-number the bigger the
hole.
• Few lenses provide a range of
apertures greater than eight stops
• A lens with a larger aperture is
considered “faster” than a lens with a
smaller aperture. Faster lenses work
better in low light situations than do
slower lenses.
• The size of the lens
opening (aperture)
controls the
amount of light that
passes through the
lens.
• Each setting is one
“Stop” from the
next, meaning,
each lets in twice
as much light as
the next smaller
opening, half as
much as the next
larger opening.
Aperture and Depth of Field
• Depth of Field is the area from
near to far in a scene that is
acceptably sharp in a
photograph.
• As the Aperture changes, the
Depth of Field Changes.
• The smaller the Aperture the
larger the Depth of Field
• Top photo – f/2 (large aperture,
small DoF)
• Bottom photo – f/16 (smaller
aperture, larger DoF)
Shutter Speed and Aperture
Together
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Both Shutter Speed and Aperture
affect the amount of light entering
the camera.
To get a correctly exposed picture
(neither too light nor too dark) you
need a combination of SS and A
that let in the correct amount of
light for a scene and film speed
Equivalent Exposures, Once you
have the correct combination of
SS and A, you can change one
setting as long as you change the
other in the opposite direction.
Remember - Shutter Speed
affects the sharpness of moving
objects, Aperture affects the depth
of field, sharpness from near to far
Sunny 16
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The Sunny 16 rule (aka the Sunny f/16 rule) is a method of estimating
correct daylight exposures without a light meter. Apart from the obvious
advantage of independence from a light meter, the Sunny 16 rule can also
aid in achieving correct exposure of difficult subjects.
The rule serves as a mnemonic for the camera settings obtained on a sunny
day using the exposure value (EV) system.
The basic rule is, "On a sunny day set aperture to f/16 and shutter speed to
the [reciprocal of the] ISO film speed [or ISO setting].”
For example:
– On a sunny day and with ISO 100 film / setting in the camera, one sets the
aperture to f/16 and the shutter speed to 1/100 or 1/125 second (on most
cameras 1/125 second is the available setting nearest to 1/100 second).
– On a sunny day with ISO 200 film / setting and aperture at f/16, set shutter
speed to 1/200 or 1/250.
– On a sunny day with ISO 400 film / setting and aperture at f/16, set shutter
speed to 1/400 or 1/500.
Sunny 16
• What settings would
you choose for a
Sunny Day using 200
ISO Film?
• f/16 , ISO 200, 1/250
• An Overcast day
using 200 ISO film?
• f/8, ISO 200, 1/250
Types of Cameras
Single-Lens Reflex (SLR)
Rangefinder/Viewfinder
Twin-Lens Reflex
Point and Shoot
View Camera