Mapping Cameras Flashcards
Systems for acquiring _____? rely on the basic components common to the familiar handheld cameras we all have used for everyday photography. These systems include:
Lens
Light-sensitive surface
Shutter
Camera body
System; to gather light to form an image
Lens
System; To record the image
Light-sensitive surface
System; Controls entry of light
Shutter
System; A light-tight enclosure that holds the other components together in their correct positions
Camera Body
Aerial Cameras (Analog) include these components in a structure that differs from that encountered in our everyday experience with cameras:
Film Magazine
Drive Mechanism
Lens Cone
Whereas other cameras may have been designed to acquire images (for example) of very large areas or under unfavorable operational conditions, the design of the ______? is optimized to acquire high-quality imagery of high positional fidelity; it is the ______? that forms the current standard for aerial photography.
Metric Camera
A ______? design differs from an analog camera because the image is captured by digital technology, _____? do not require the film and the complex mechanisms for manipulating the film.
Digital Camera
The _____? gathers reflected light and focuses it on the focal plane to form an image. In its simplest form, a _____? is a glass disk carefully ground into a shape with nonparallel curved surfaces
Lens
The change in optical densities as light rays pass from the atmosphere to the lens and back to the atmosphere causes _____? of light rays
Refraction
Optical characteristics of lenses are determined largely by the _________? and the ______?
Refractive index of the glass, The degree of curvature
Imperfections in lens shape contribute to _______?, a source of error that distorts images and causes loss of image clarity.
Spherical Aberration
Most aerial cameras use ________?, formed from many separate lenses of varied sizes, shapes, and optical properties.
Compound Lenses
The ______? joins the centers of curvature of the two sides of the lens.
Optical Axis
Although refraction occurs throughout a lens, a plane passing through the center of the lens, known as the ________?, is considered to be the _______? within the lens cameras.
Image Principal Plane, Center of Refraction
The image principal plane intersects the optical axis at the ________?
Nodal Point
Parallel light rays reflected from an object at a great distance (at an “infinite” distance) pass through the lens and are brought to focus at the principal _____? — the point at which the lens forms an image of the distant object.
Focal Point
The ______? passes through the nodal point without changing direction; the paths of all other rays are deflected by the lens.
Chief Ray
A plane passing through the focal point parallel to the image principal plane is known as the _______?
Focal Plane
In a simple positive lens, the ______? is defined as the distance from the center of the lens to the focal point, usually measured in inches or millimeters.
Focal Length
For a given lens, the focal length is not identical for all wavelengths.
E.g. blue light brought to a focal point with a shorter distance than red light.
This effect is the source of ______?
Chromatic Aberration
The field of view of a lens can be controlled by a ____?, a mask positioned just in front of the focal plane.
Field Stop
An _______? is usually positioned near the center of a compound lens; it consists of a mask with a circular opening of adjustable diameter.
Aperture Stop
_____? is measured as the diameter of the adjustable opening that admits light to the camera.
Aperture Size
