The
natural light
The length of shadows decreases
as the sun rises, in the early morning shadows are long and colour temperature
alters from red to blue-white. This latter change is almos invisible to humans
because our brains perform a kind pf white balance control that ensures we see
all light as neutral white light. White balance settings, use daylightthrough
noon on a sunny day, cloudy add warmth to landscape scenes, shade when subject
is heavy shade, incandescent when tungsten light, fluorescent lighting primary
light source, flash when electrnic flash is primary light source
Pre-shadows
WB setting
When you are photographing under
a consistent light source, such as in a studio, it is possible to measure the
exact Kelvin value of the lighting and to set a specific WB to match. When shooting
outdoors under natural light, when the colour temperature of light can be
changing constantly, calculating the exact Kelvin temperature is impossible for
all practical purposes.
Fill-in flash
Fill-in flash is artificial light
to increase illumination in shadow areas, thereby reducing contrast. The
built-in pop-up flash on the camera is useful for fill-in flash but it suffers
from being positioned directly above the camera lens, which create frontal and
direct lighting. diffusing the flash will soften.
Working
in low light
Use manual exposure mode and
allow for setting slow shutter speeds via Bulb or Time setings, which enables
the shutter to be open for very long periods(minutes or even hours). To avoid
camera shake and image blur it is essential to use a tripod, keep its centre of
gravity low and avoid using the centre column, also a cable release will avoid
causing camera movement when triggering the shutter, an alternative is to use
the self-timer to trigger the shutter but this isn’t feasible when using the
Bulb/Time setting, and if the camera has it use the mirror lock-up function.
How
do I focus in low light
Most auto-focus systems in modern
cameras operate using a system known as contrast-detection. In low light
conditions contrast levels are often too low for AF to work effectively, if the
scene you are photographing contains a bright light, such as a streetlight,
that is along the same focal plane as your subject, then this can be used as
the focus point. Focus can then be lockedand the composition reframed, much as
if you were focusing on an off-centre subject. This technique can also be
applied in manual focusing mode. Another option is to use a very powerful torch
such as the IM+ candle. A third option
is to use intuitive guesswork making use of the focus distance scale on the
lens barrel and optimizing depth of field. Some professional specification
cameras have interchangeable viewing screens, enabling the standard screen to
be replaced with a special extra bright screen designed for night photography.
