it is the action of recording radiant energy that produces a change on a material of substance sensitive to such energy.

5 types of exposure

the illumination falling from a source or sources onto a scene or subject is measured

from an 18 percent gray card held at the subject position or area or from a key subject area like the skin.

both electrical flash unit and flash bulbs provides light in a relatively high illumination level in a short period of time.

flash exposure maybe computed by the use of the “guide number” of a flash unit. a guide number is usually dependent on the film speed and the light output. electronic flash units guide number is base

flash of the camera or held close to the camera with a bracket provides a direct, hard light. because it puts the maximum level of light on the subject, it creates a problem of the “red eye” in a human subject, harsh shadow of subjects with a near background, and reflections from a shiny spot in the background.

with this unit, the flash can be moved away from the camera at arm’s length or more. when the flash unit is used in this manner, the photographer can improve effectiveness of the flash lighting.

more than one flash unit is used, one is connected to the camera with a flash cord while the other is attached to a “slave” unit.

when you want to eliminate is used illumination to shadow areas or subject so detail that otherwise will not appear clearly in the final picture.

the shutter speed is set at “B” and once the shutter is open, the flash is activated or fired released manually. then the shutter is released or is closed.

is another form of open flash technique. with this technique, the flash unit is moved place to place, fired manually until all areas of the scene or large subjects are fully illuminated and the shutter is then released or is closed.

instead of the lighting going directly to the subject, it is bounced on light colored ceilings or walls near the subject. this will give a softer effect on the subject, and also diminish or reduce harsh shadow that will be casted by the subject.

a modified type of bounce flash by using an umbrella lined with silver, white, blue or amber colored especially made for photography. the flash is mounted on the handle of the umbrella aimed at its inside center. this inside center is the aimed toward the subject.

this is a round or circular flash unit usually placed around the outer end of the camera lens. this is used for taking close ups or macro photography especially in medical photography.

two types of filter used in photography

this are made either of glass or acetate. this are used primarily to control exposing energy ( visible wavelengths, ultraviolet, infrared rays ) and the composition of working illumination in areas where sensitized materials are handled.

this is used in special photographic procedure like in infrared luminescence most pictures are taken by white light falling on a colored object; very few things in nature are truly neutral white light is the sum total of all colors of the rainbow while black is the absence of all colors.

a filter used to change the color quality of the exposing light in order to secure proper color balance for artificial light films.

the used to change the over all color balance of photographic result obtained with color films and to compensate for deficiencies in the quality of exposing energy.

this filter is used when light is too bright to allow the use of desired f - number or shutter speed with a particular film

this is used to reduce or minimize reflections on subjects like water glass, and highly polished surfaces.

it is the change of apperance and orientation of objects when seen from two viewpoints. it is also used to refer to the distance between the viewpoints themselves.

this is a device that opens to uncover the film to make an exposure for an accurately timed interval then closes automatically.