Depth of field.The distance that is sharp beyond and
in front of the focus point at a given f-stop.
Depth of focus.The amount of sharpness that ex-
tends in front of and behind the focus point. Some lens’s
depth of focus extends 50 percent in front of and 50 per-
cent behind the focus point. Other lenses may vary.
Diffusion flat.A portable, translucent diffuser that
can be positioned in a window frame or near the subject
to diffuse the light striking him or her.
Dragging the shutter.Using a shutter speed slower
than the X-sync speed in order to capture the ambient
light in a scene.
Feathering.Misdirecting the light deliberately so that
the edge of the beam of light illuminates the subject.
Fill card.A white or silver-foil-covered card used to
reflect light back into the shadow areas of the subject.
Fill light.Secondary light source used to fill in the
shadows created by the main light.
Flash fill.Flash technique that uses electronic flash to
fill in the shadows created by the main light source.
Flash main.Flash technique in which the flash be-
comes the main light source and the ambient light in the
scene fills the shadows created by the flash.
Flashmeter.A handheld incident meter that measures
both the ambient light of a scene and when connected to
the main flash, will read flash only or a combination of
flash and ambient light. They are invaluable for determin-
ing outdoor flash exposures and lighting ratios.
Foreshortening.A distortion of normal perspective
caused by close proximity of the camera/lens to the sub-
ject. Foreshortening exaggerates subject features. noses
appear elongated, chins jut out and the backs of heads
may appear smaller than normal.
45-degree lighting.Portrait lighting pattern charac-
terized by a triangular highlight on the shadow side of
the face. Also called Rembrandt lighting.
Full-length portrait.A pose that includes the full fig-
ure of the model. Full-length portraits can show the sub-
ject standing, seated or reclining.
Gobo.Light-blocking card that is supported on a
stand or boom and positioned between the light source
and subject to selectively block light from portions of the
scene.
Gutter.The inside center of a book or album.
Head-and-shoulder axis.Imaginary lines running
through shoulders (shoulder axis) and down the ridge of
the nose (head axis). The head-and-shoulder axis should
never be perpendicular to the line of the lens axis.
High-key lighting.Type of lighting characterized by
low lighting ratio and a predominance of light tones.
Highlight.An area of the scene on which direct light
is falling, making it brighter than areas not receiving di-
rect light; i.e., shadows.
Highlight brilliance.The specularity of highlights on
the skin. A negative with good highlight brilliance shows
specular highlights (paper base white) within a major
highlight area. Achieved through good lighting and ex-
posure techniques.
Histogram.A graph associated with a single image
file that indicates the number of pixels that exist for each
brightness level. The range of the histogram represents
values from 0 to 255, reading left to right, with 0 indicat-
ing “absolute” black and 255 indicating “absolute”
white.
Hot spots.A highlight area of the negative that is
overexposed and is without detail. Sometimes these areas
are etched down to a printable density.
ICC Profile.File that contains device-specific infor-
mation that describes how the device behaves towards
color density and color gamut. Since all devices commu-
nicate differently‚ as far as color is concerned, profiles en-
able the color management system to convert device-
dependent colors into or out of each specific color space
based on the profile for each component in the work-
flow. ICC profiles can utilize a device-independent color
space to act as a translator between two or more different
devices.
Incident light meter.A handheld light meter that
measures the amount of light falling on its light-sensitive
cell.
JPEG (Joint Photographic Experts Group).An
image file format with various compression levels. The
higher the compression rates, the lower the image qual-
ity, when the file is expanded (restored). Although there
is a form of JPEG that employs lossless compression, the
most commonly used forms of JPEG employ lossy com-
pression algorithms, which discard varying amounts of
the original image data in order to reduce file storage
size.
Main light.The main light in portraiture used to es-
tablish the lighting pattern and define the facial features
of the subject.116 CHILDREN’S PORTRAIT PHOTOGRAPHY HANDBOOK