Re: Building a Light Tent

[Jim Brick <jim@brick.org>]

At 09:55 PM 8/23/97 -0400, you wrote:
>
>Is there a better way to meter for this type of still life?
>
>Richard Clompus, OD
>

An incident meter, laying at the subject plane, with the dome pointed at
where the lens will be. Always works. This is what incident meters are for.

You also might try placing the instruments on a clear sheet of glass, a few
inches above a piece of white plexiglas (opal or whatever) with light from
the back of the plexi. You adjust the level of the background illumination
(with the meter) so that it is 2-1/2 stops brighter than the instrument
illumination. This will give you a shadowless, non-bleeding, white
background. Or you can adjust the background light level to levels of gray
if you need separation. Or use colored gels on the background lite. This is
difficult to describe. I hope I made sense. I suggest this because laying
instruments directly on a background can sometimes be pretty dull, and
contain complicated shadows. A background in focus can also be distracting.
You can probably think-up other combinations. My point is to remove the
background to a point where it is not in focus, doesn't bleed around the
sides of the instruments, and doesn't contain complicated shadows.

I've used this method (illuminated distant background and tent) many times
when shooting shiny silver instruments. For a tent, I used a white sheet
draped over a large metal ring, suspended from the ceiling. A ring also at
the bottom for stability. A long vertical slit down one side to allow
placing the camera at any level. Also across the top for shooting from
above. Close the slit below and above the camera lens. And anywhere else
that it gaps open. I've used both tungsten lights (3200 & 3450) and
appropriate film, and strobe with daylight film to illuminate the tent and
background. If you use the plexiglass background, tungsten is easier to
control.

Just a thought about what worked for me in the past.

Jim