23 Feb 2008 03:21:36 | Jakob Jelling
Looking at the most intricate details of the digital camera as a
technologically advanced device a lot of functions come into
play. Such s a point is that of the digital camera metering.
This discussion focuses towards that intention of understanding
and knowing the details of the component. Basically speaking the
metering system in a digital camera measures the amount of light
in the scene and calculates the best-fit exposure value based on
the metering mode explained below. Automatic exposure is a
standard feature in all the digital cameras. All that is
requires to be done is select the metering mode, point the
camera and press the shutter release. Most of the time, this
will result in a correct exposure. The detailed explanation and
analysis of the entire process is as follows in the next lines
of this discussion.
The metering method defines which information of the scene is
used to calculate the exposure value and how it is determined.
Metering modes depend on the camera and the brand, but are
mostly variations of the following three types. Primarily,
matrix or evaluative metering. This is probably the most complex
metering mode, offering the best exposure in most circumstances.
Essentially, the scene is split up into a matrix of metering
zones, which are evaluated individually. The overall exposure is
based on an algorithm specific to that camera, the details of
which are closely guarded by the manufacturer. Often they are
based on comparing the measurements to the exposure of typical
scenes.
Next comes the center-weighted average metering. This is
probably the most common metering method implemented in nearly
every digital camera and the default for those digital cameras
that don't offer metering mode selection. This method averages
the exposure of the entire frame but gives extra weight to the
center and is ideal for portraits. Another important is the spot
or partial metering. The spot metering allows the user to meter
the subject in the center of the frame or on some cameras at the
selected AF point. Only a small area of the whole frame is
metered and the exposure of the rest of the frame is ignored.
This type of metering is useful for brightly backlit, macro, and
moon shots. Again a lot has been revealed and a lot remains to
be done so, yet the rudimentary foundation of string
fundamentals can be established via the lines of the above lines
of this discussion. It is only hoped that the lines get their
true respect from the readers of them and users of the digital
camera to properly deliver the due respect that the digital
camera metering technique deserves.
About Author :
Jakob Jelling is the founder of http://www.snapjunky.com. Visit
his digital camera guide and learn how to take better pictures
with your digicam.