Pat:
FWIW, video has 30 frames a second. It makes it real easy to set-up the same
start point.
The editor presses two buttons to mark the spot on each tape machine, rolls 'em
back five seconds (pre-roll), starts them with a controller, and presto chango,
they are in sync.
Trust me, there is more to it than that (video over video, etc.), but that's how
they get 'em matched up.
Rex Weatherford wrote:
> washburn wrote:
>
> > Hey Gang!
> >
> > I was watching a downhill skiing event awile back, I'm not quite sure
> > why, and I saw a very neat trick on the replay. They showed two skiers
> > going down the hill together in real time, at their real relative
> > positions on the course, camera panning to follow the action, and they
> > were looking absolutely real with the background being crystal clear
> > with no signs of a "double exposure" trick. Not a cheap split screen
> > trick. If you didn't know better, you would swear that there were two
> > skiers on that hill...until they appeared to ski right through each
> > other.
> >
> > The only way I can think that they did it was to hook a motion
> > controlled camera into the timer system. The shot was set up on a short
> > section about halfway down the hill, and it lasted about 10 seconds.
> > When the skier trips the timer, it starts a pre-defined waiting time,
> > set up during practice runs. When the pre-determined amount of time has
> > passed, the camera goes into a pre-programmed and highly precise motion
> > routine right when the skier appears in the shot, and it pans along the
> > run with the skier. Do this with each skier, and you have the ability
> > to superimpose one run onto another with precision relative to their
> > times, and you can watch them both take different lines.
> >
> > Naturally, I immediately thought of all the cool applications for
> > autocross and ProSolo. Wouldn't it be amazing to have this kind of aid
> > in comparing your run to the fast guys? Wouldn't it also be a very cool
> > as a part of a televised event? No point to this, I was just impressed
> > enough that I wanted to share.
> > --
> > Patrick Washburn <washburn@dwave.net>
> > Wausau, WI Land of Cheese
> > 95 DS Neon
> > Moooooooooo.
--
Matt Murray
mailto:mattm@nassau.cv.net
mailto:mdmurray@gwns.com
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