OT UW color filming
vince garcia
had invented I think was called AQUA COLOR. He'd invented some sort of
filter or something that permitted spectacular full color filming
underwater without need of artificial lighting. What I saw was
absolutely amazing and looked like a technological breakthrough in
undersea cameras. That was about the time I got out of the diving
business altogether and I never followed up to see what, if anything,
resulted from the invention. Anyone familiar with this item or know what
happened with it?
v
Bob Botts
I've never heard of it, Vince.
The product sounds to me as if it was attractive to U/W
photographers because it offered sensitivity to hues that
were sympathetic to U/W photos. I suspect that the product
didn't appeal to a broad enough market to enjoy commercial
success.
There's a difference however, between using a strobe and/or
filter to maintain colour balance with specific film types
(e.g.. daylight film), and using a strobe to illuminate a
subject that is too dim to render a proper exposure.
Filters do not make an image brighter, instead they
selectively supress wavelengths other than the selected band
pass. IOW, a filter will not help to capture information
that was too dim to register a proper exposure in the first
place.
These days a common way to deal with colour shift is by
digitizing the image and correcting the shift in a software
program such as "Photoshop". This allows the technician to
render an aesthetic final image, however, no software
program can restore information that was never captured
during the initial exposure, so although the hard copy may
be visually appealing, there will be detail missing.
The most common ways to make a stock film more sensitive to
light, is either by cooling, (i.e. there are 'cold cameras'
which use a dry ice chamber to lower the temperature of the
film which reduces it's reciprocity failure), and/or by
hypersensitizing the film, (baking it in a forming gas under
pressure for a few days, which replaces the water molecules
with a hydrogen-nitrogen mixture). Neither method will make
film as sensitive as a CCD chip (in fact a CCD chip is about
10x as quantum efficient), plus a CCD chip is sensitive to a
wider range of wavelengths, (most dramatically in IR
wavelengths).
One can push process film to bring out detail in
underexposed sections of film, but, this is technically
different from making a film more sensitive to low light
conditions. There is a penalty to pay for push processing,
in the form of increased contrast and grain size. One can
also push process hypersensitized film, but it will still be
grossly inferior to a CCD chip for collecting photons from a
dim source.
Cheers... Bob
vince garcia
Thanx for the post! I do not recall exactly what the heck they did to
make the process work; i'm only guessing a filter. I only recall my jaw
dropping as they showed either video or (probably film) of some shots
from the Caribbean. Yes you could see the water, but if you can imagine
the fish and sea bottom having lost none of their vibrant color spectrum
that's what I was privileged to see. (How often do you see nice clear
reds or orange underwater w/out light?) My thought was "My God, this is
the greatest breakthrough in history for undersea filming".
Wish I knew what the heck happened; it would be awesome if the process
were available to the average diver
v