nospam@please.invalid (AnthonyL) wrote:
>I'm trying to take some photos of some posters (typically 4ft x 3ft or
>thereabouts). Some are mounted in glass frames.
...
>But I get unwanted reflections with the ones mounted behind glass.
>This occurs whether I try using the natural light or the Tungsten
>lights in the room. I've tried a polarizing filter but not to good
>effect. One problem is that if I use the natural light the image is
>too dark for me to see whether there is a reflection in the
>viewfinder.
...
>What techniques can I try to get good images?
Reflections are a pain. Generally the problem is that
for each and every light source, there are an entire set
of reflections from any particular glossy surface.
Hence each window will have a reflection, each ceiling
light will too, and so will any other source of light.
If you move the camera to get rid on one reflection, you
are sure to then find another (or half a dozen others).
The trick is to reduce it to just one single point
source of light. For that, a relatively dark room is
idea, so you have a good chance!
Use a single flash, located relatively far away from the
posters, and do not use any kind of reflector or diffuser
on it. That will make it appear as a single spot on any
reflective surface and may allow you to position the
flash and the camera such that there are no reflections
in the image itself (it might only allow you to reduce
their effect though).
You also want the flash to be much brighter than any
other illumination, so setting it for manual at full
power and then using manual exposure on the camera will
help too. And if possible, cover the window and turn
off other lights!
You'll almost certainly have to move around a bit,
taking multiple shots to view the results looking for
positions that result in the least amount of visible
reflection. A modeling light might help a bit, but
it won't be bright enough to see everything, so it's
just a case of shoot and view, shoot and view until you
get it right.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com