Thanks Steve, I know this is a stupid question. but what is a
histogram.
Hi Donna,
A basic explanation, and probably all that I am capable of, is
that it's a bar graph of what your camera's light meter "sees,"
and what your camera sees depends on settings such as shutter
speed, aperture and ISO speed setting - things you can control..
Black is on the left, gray in the middle and white on the right.
Everything else is in between. The meter "sees" in black&white,
by the way. The height of a bar at any given point on the
graph indicates the amount of light of that tone (Shay Stephen's
word) or brightness in your image. So, a picture of a gray sky
may give you a histogram with one high bar somewhere near the
middle of the graph.
In practice, though, most images will contain a range of tones from
dark to light. The tops of the bars of the histogram will usually
form a curve. For a proper exposure, the idea is to keep the curve
from piling up at the extreme edges of the graph. If the curve hits
the left side, part of the image will be underexposed. If it hits the
right side, part of the image will be overexposed. The concensus
around here seems to be that exposure should be set so that the
curve is as far to the right as possible without hitting or, especially,
stacking up on the right edge. This will generally get you an
acceptable exposure. Of course, if you become familiar with the
exposure values (EV) of various objects as defined by the zone
system, you may want to override this loose rule.
There was a very good explanation of all this written by Shay Stephens
some time ago. The text is still there but, unfortunately,
the images are not. Still, you may get some useful info by
reading it. Click here:
http://forums.dpreview.com/forums/read.asp?forum=1009&message=3522427
Have fun with your new camera. Your excitement
will be
rewarded!
Steve
