Forensic Photography M4

It is a latin word which means " chamber"

It is defined as light tight box with a means of focusing the image with the aid of a " pinhole or lens", a shutter at one end

A box designed to keep light out and serve as frame to hold other parts

Designed to collect or to focus the reflected light reaches the film

Designed to control the time during which the light reaches the film

Located at the opposite side of the lens, designed to hold firmly the sensitized material to prevent the formation of multiple or blurred images

Designed to determine the field of view of the camera or the extent of the coverage of the given lens

It suggests an enclosure devoid of light. This would prevent light from exposing the sensitized material inside the camera

Responsible for focusing the rays of light coming from the subject. Provides sharpness to the image that will be projected on the surface of the sensitized material inside the camera. It consists of several pieces of glass mounted in a metal cylinder called a " LENS BARREL"

Always thicker at the center and thinner at the sides. Light passing through it is bent toward each other on the other side of the lens, meeting at a CERTAIN POINT. It produces a REAL IMAGE

Always thinner at the center and thicker at the sides. Light passing through it is bent away from each other as if coming from a point

Defined as the SETTING OF PROPER DISTANCE in order to form a SHARP IMAGE

It is usually found at the lens barrel, indicating pre-set distance in feet or meters

A mechanism that measures the ANGLE OF CONVERGENCE OF LIGHT coming from the subject, as seen from two apertures.

Through the rangefinder, the image of the object appears cut into halves and separated by a straight line when the lens is not on focus

Through the eyepiece, a single image is seen doubled indicating that the subject is out of focus.

Focusing is done by directly observing the image formed, with a screen placed behing the taking lens.

Possible only with wide angle lenses

Three settings of focusing

The light gathering power of lens is indicated by its relative aperture. This can controlled by means of diaphragm

The measure of the zone of acceptable focus. It is the distance from the nearest object in good focus to the farthest object in good focus

Shorter Focal length, Small lens Aperture, Greater Subject distance

Longer focal length, larger lens aperture, shorter subject distance

A term used to describe " SHARPNESS". To establish a standard for good focus, lens designers reason that " EVERY TINY POINT ON THE SUBJECT SHOULD BE A TINY POINT IN THE IMAGE".

Refers to the minute amount the film plane can move toward or away from the lens before the image looks blurred, assuming the subject doesn't move at all.

Defined as the nearest distance at which lens is focused at infinity with a given diaphragm opening, providing maximum depth of field

The distance measured from the optical center of the lens to the film plane when the lens is set to focus at infinity position

A lens with a focal length of less than the diagonal of its negative material. It has a short focal length (14mm-35mm) that allows a wide angle of view but low magnification.

Increased depth of field ( LESS FOCAL LENGTH= MORE DEPTH OF FIELD)

Extends the angle of view up to 180 degrees. Has a focal length of 8mm and 10mm. When pointed straight up, it records the sky all the way down to the horizon in all directions

A lens with a focal length approximately equal to but not more than twice the length of the negative material. It has a focal length of 45-55mm.

A lens that has a focal length equal to or more than twice the diagonal of the negative material. It has a NARROW ANGLE OF VIEW.

Lenses with variable focal length ( focal length that can be changed to alter the image on the film). It's main advantage is that they allow you to change focal length quickly without changing lenses.

Light rays that enter lens near the center are refracted less than those that enter near the edge. This causes rays from the same object to be OUT OF FOCUS relative to each other

Occurs when light rays enter the lens at an angle causing different parts of the lens to focus the light at different points, resulting in a blurred, comet shaped for off-axis points

Also knows as COLOR FRINGING, it is a lens distortion that causes color halos or fringing around the edges of objects in a photo.

Occurs when a curved lens distorts an image into a curved plane rather than a flat one

An optical error that causes light to focus into lines or ellipses instead of points. It occurs when a lens is used over a wide field or when light hits a lens at an angle

An optical aberration that changes the shape of an image, making straight lines appear curved. It is caused by different areas of a lens having different focal lengths.

Also known as pincushion distortion, this occurs when image points are displaced outward from the center

Also known as barrel distortion, this occurs when image points are displaced inward from the center

Corrected for chromatic Aberration

Corrected for distortion

Corrected for astigmatism

Corrected for astigmatism with higher correction to color

Corrected for Spherical Aberration. The aspherical lens element has no spherical shape and is designed to bring all the light rays to focus at the film plane for a sharp image.

A contraption or device used to block the path of light passing through the lens and exposing the sensitized material in a pre-determined interval of time

Located in the lens usually between the elements of the lens. Made up of metal leaves and it's action moves from the center toward the side, then closes back to the center

Near the focal plane of the sensitized material. Usually made of cloth curtain but also available in metal. Some of it's shutter move vertically to create opening, while other camera models use a horizontally moving shutter

It allows you to control the length of time the film will be exposed to the light that passes through diaphragm opening

Continuously keeps the shutter in the open position while the shutter release button is still pressed

Keep the Shutter in an open position with one press and close it with another click

Determines the entire scene coverage that will be recorded on the film inside the camera during exposure.

Transfers the exposed film to take up spool and advances the remaining unexposed film behind the lens, preparing it for another exposure

The light gathering power of the lens

Controls the speed of opening and closing of the shutter to regulate the quantity of light that will expose the sensitized material inside the camera

Provides sharpness and clarity to the objects being photographed

Comes in different lengths and allows you to fire the camera from a distance. Attached to the shutter release of the camera and used to release the shutter to prevent unnecessary movement caused by pressing the shutter release button, permitting longer exposure

Could be a flash bulb or electronic flash, synchronized with the action of the shutter

Determines the intensity of light that strikes the subject and affects the film. Used to determine the correct amount of exposure

Used in close up photography

It prevents extraneous light from striking the front element of the lens, causing flare.

Transparent medium that transmits and absorbs different wavelengths of light passing through it. Made of GLASS OR GELATIN material placed in front or behind the camera lens. It is a discs of glass or negatives that stop certain colors of light from passing through to strike the film

Used to change the response of the film so that all colors are recorded at approximately relative brightness values as seen by the eyes.

Used to change relative brightness values in the photograph so that two colors, which would otherwise be recorded as nearly the same, might exhibit different brightness and great tonal difference in the final print.

Used to eliminate or reduce the effect of atmospheric haze that makes distant object appear blurred and fuzzy in the photograph

A grayish-colored filter used for reducing the amount of transmitted light uniformly without changing the color value

Capable of reducing or eliminating reflections on highly reflective surfaces

The smallest and simplest type of camera to operate. Equipped with a simple lens system. Inexpensive and allows you to focus your subject even at lowlight levels

Allows you to view and focus through the same lens that captures the image onto the film. The word reflec stands for reflection, indicating that the image seen in the viewfinder is bounced off a mirror in the optical path between the lens and the eye. ELIMINATES PARALLAX ERROR

A type of camera with two lenses. Uses a mirror on one lens ( upper lens) to reflect an image of the scene upward onto the viewing screen. The fixed mirror is used for viewing and focusing, while the other lens is taking lens

The most sophisticated and largest type of camera. Built with a lens at the front and a viewing screen at the back. Focusing is achieved by moving the lens forward or backward until a sharp image is seen on the viewing screen. PLAYS AN IMPORTANT ROLE IN POLICE PHOTOGRAPHY, ESPECIALLY IN THE REPRODUCTION OF DOCUMENTS AND PHOTOMICROGRAPHY