spot meters are good tools for the photographer especially in a controlled
lighting situation like a studio. They work differently to hand held meters
in they they measure reflected light (light bouncing off the subject) rather
than incident (light falling on the subject) so whats the difference, you
ask? objects have different reflectance values so you have to bear in mind
weather you are using a reflected reading or an incident reading and adjust
the exposure according to the percieved 'brightness' of the subject.
Heres an example. all meters give a reading to 18% average. a handheld
meter will give 18% of the ambient light and not take into account the
brightness of the subject, so if somehting is very white, you will need to
close down the aperture, because its not grey, its white.ie, its reflecting
80% instead of 18%.If you shoot what the meter says, the subject will be way
Now heres the tricky bit. Spot meters are the opposite. A spotty will tell
you that that white object is in-fact grey18%, so if you shoot what the
meter says the white object will come out way to dark.(and probably
everything else around it will be waaaay to dark) so you need to open up
Some spot meters have a zoom and give you from 1degree to 5degrees, exposure
does not generally have any direct relation to format or lens focal length.
They are handy if you need to check highlight levels or a distant object
that is to in ambient light. They are a great tool, but it's quiite easy to
get burnt by using one if you dont really know what your doing, so
experimentation is the key.
hope this helps
"Lunaray" <com> wrote in message