Hmmm, that's interesting Tony. I'd like to see the animations that you
created that effectively use camera depth of field effects on the dome.
In my experience, using DOF on the dome doesn't work unless you are
going for a macro photography look or an "effected" look. It tends to
make things look small and unnatural. I noticed this when I first
experimented with using DOF on the dome and so I tried to figure out why
it often works well when animating for TV or film, but seemed to destroy
the "immersiveness" of a dome movie. I came to two conclusions. First,
full dome and panoramic video is "immersive" because it puts you in the
picture. It's more simulative than flat screen video. It makes the
viewer feel like they are actually IN an environment, watching the
action unfold. This is different from most flat screen video/film,
which is more third person... like a window onto the action that
immerses you in a less visceral way. If you accept that dome video is
more simulative/immersive than flat screen, think of the distance from
the screen to our eyes. For most domes, it's far enough away that it
falls into the infinite focus distance of our eyes. In other words, we
don't perceive any DOF effect on objects at this distance. Also, if you
are doing space imagery, think of the scale that you are working at. If
you are orbiting the Earth, looking at the moon, your eyes (or a camera)
don't have to focus differently to view the two objects because they are
both at the infinite distance range. The second conclusion that I've
come to has to do with the size of the screen. Typically, DOF effects
are used to draw a viewers attention to a certain object on the screen.
It's a very effective trick when the entire screen is in your field of
view, but that's not the case with a dome. When you defocus an
environment to draw attention to a particular area of the screen, your
creating HUGE areas of defocus that can be disorienting to a viewer who
isn't already looking at the area that you want to focus attention on.
For example, if you are going to pull-focus onto an object in the front
center (say 20 degrees above the equator and front being the direction
that your seats face... hopefully all your seats face in on
direction!!), and I'm looking off to the left when you pull the focus,
my whole world suddenly gets blurry and until I have time to find the
object that you pulled into focus, i'm wondering whether it's the
display that broke or my eyes. I don't know if anyone here reads
Millimeter magazine, but a few months back they had a interview with
some of the people who filmed the Imax movie with the Cirque de Soliel.
I don't have the article at hand to refer to, but I remember reading
that one of the technical problems that they had to deal with was that
natural depth of field looked unnatural when projected on a huge Imax
screen. I believe they had to work quite hard to reduce it so that it
wouldn't be distracting. Perhaps we are dealing with the same
phenomena? I'd like to hear other people's opinions. I'm very
interested in artist's aesthetic observations on dome video production
and I applaud Tony for posting something in this direction. Cinema has
had 80+ years to develop a set of conventions and a language. We're
still in the phantom train ride stage. We are just getting started.
Brad Thompson - bthompson@...
Digital Animation & Design - Spitz, Inc.