In his reply on shooting portraits, Deric Soh wrote:
..........snip ...............
>
> Like me, if you're using the 105mm, you'd be too far away (assuming
> you're
> not doing micro shots but head and half body shots) to have red eye come
> out
> on your shots. Also, you'd be using the vertical format, so no worries.
> Why would you want to use a bracket in this case? When in the vertical
> format, your flash is already on the side of the camera....plus by using
> the
> bracket, you loose the 3D Matrix/Matrix metering.
>
..........snip ...............
I'll humbly take exception to a few points here. Red eye is caused
by light from the flash entering the subject's eyes and bouncing off the
retinas directly back to the camera lens. The risk of red eye is therefore
greatest when the axis of the flash and the axis of the lens are close
together and nearly parallel. Since I can't draw a picture here, one way to
envision it is to draw an imaginary letter "V" from the flash to the
subject's eye and back to the camera lens (i.e., the point of the V is at
the eye). The narrower the angle of the V, the greater the chance of red
eye. If you draw this out, you'll note that the V gets narrower as
camera-to-subject distance increases and so moving farther away increases,
not decreases, the red eye possibility. It also doesn't matter if the flash
is above, below, or to the side of the camera -- the only things that matter
are lens-to-flash distance (the farther the flash from the lens, the less
the chance of red eye) and the camera-to-subject difference (the farther
from the subject, the greater the chance of red eye, unless, of course,
you're so far away that couldn't see red eye even if it were present).
There are also a couple of reasons for wanting the flash higher
above the camera. First, the light is generally considered more natural
looking (most of the lighting we usually see is from above) and second, if
the subject is close enough to the background to cast a shadow, a high flash
will keep the shadow low and, hopefully, out of the picture.
And to echo the sentiments of a number of recent posting, thanks to
Andrew, welcome to Henry, and happy holidays to all.
Regards
Dennis
