h a l f b a k e r y
The word "How?" springs to mind at this point.
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Basically the idea here is to have a sensor
on every point that changes a shot's
positioning or appearance. That's every
extension point on the tripod's legs, the
vertical and horizontal angle of the head,
and how high it's raised up. In the
camera focus, f-stop, shutter speed,
digital effects, Frames
per second--any damn
thing you can adjust. The coordinates of
the tripods feet or the dolly could be
recorded with a laser measure. Level
would also be taken into account. Once
you've decided on your shot, your
for all those factors and anything I
are saved to a file on a small hard drive
located somewhere on the camera or
tripod. This file is labeled with the time
and date. A small jpg file of the first
of the shot accompanies each file also.
(There are already tripods that hook up
the camera; I use a tripod that has a
multiple speed zoom control that plugs
to my GL2).
These files could be stored on one's
computer for later reference. Then if
neccessary, one of these files could be
loaded up on the camera and you could
match up the tripod and camera's
Likely the camera's adjustment would be
This system would be invaluable for
continuity in general and in the editing
specificially. It would be possible to go
back to the location and shoot more
footage for a time-lapse effect or to
the earlier scene--though that's merely
the beginning of the possibilities. I know
could use it.
[ato_de, May 21 2005]
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||Sorry 'bout that--when you're so
fascinated with a subject you assume
everyone else is also. Corrected.
||That seems rather uncalled for...
||So, record all degrees of freedom available to the photographer. How do you know where to set it down? GPS? Perhaps have a small camera on the tripod that takes three or four pics from seperate vantage points before taking the camera shot. 3D reconstruction could serve all the necessary calculations for tripod height, angles, and the elusive absolute position. [+]
||That's basaically what I'm going for,
||[Daseva]--I guess I didn't make it
clear--that's what the laser measure
and level is supposed to be for. But
your idea works just as well. It's all
about absolute recreation, the details
||I like the idea, I'm just a little slow and have trouble seeing how a laser and level will give you reliable coordinates for centering the tripod, and for relaying the exact location of those coordinates.
||//then I got confused about the tripod thing and dark clouds began roiling in my mind...//
||There are systems for doing this and that can even recreate, with exacting precision, camera motion during a given shot. They're called motion control rigs and they generally also record shutter angle, lighting control commands, frame rate (exactly) and can operate both in real and non-real time. Both the British Mark Roberts (Cyclops) and the American Tondreau systems are world-class examples of motion control systems.
||Smaller systems like the Ultimatte Memory Head precisely record camera motion, placement and camera attributes within a smaller set of variables.
||There are also software systems that can, with visual analysis of a given set of frames, yield the exact focal lengths, exposures and film plane or imager locations in 3D space in relation to a known target coordinate in the images. These systems are known as "camera matching" systems and are typically used to recover physical camera coordinates and attributes in a scene so that the setup can be used to establish a theoretical camera for generating synthetic 3D CGI elements to be believably added, or composited, into a physical scene. This data can be used, however, to re-establish a physical camera's position and optical attributes, with great precision and they have been used for insert work during post-production to remedy a broken shot. Premier systems include those written by Real-Viz, Side-Effects (Houdini) and others.
||Finally, cameras like the Z-Cam record meta-data, on a per-frame basis, that contains, in addition to the optical attributes, the 3D data about the physical environment of that which is being shot. Again, this data is typically used for synthetic, or virtual, set work but can be reverse-engineered to establish real-world camera placement.
||Of course, none of these are exactly like your proposed system but are merely existing methods used in the quest for visual continuity.
||OK, so it exists already. Good to know,
I'll make use of it someday. When I have
the huge lumps of money these systems
require of course.
||Well, you can build a motion control rig yourself, you know. There's lots of people who have at the hobby level. As robots go, they're fairly simple and there are lots of resources out there.
||Even though I had no idea what you were talking about, it sounds pretty good to me. Too bad it was already invented.
||Eugene's method is quite different from the ones I mention and mine haven't any geographical reference.
||EXIF does provide fields for GPS coordinates but that is a still format, generally, save MJPEG.
||About the laser measure and level--it's
just my crude notion for a way to
recreate the actual position of the
camera and tripod. GPS would be
useful, yes--but the GPS units I've seen
aren't as accurate as would be
preferred. At least if the GPS position
was recorded you'd be reminded of the
exact location in which you shot. Well,
||GPS is accurate to within about 15m. It could remind you
of where you took the shot, but you'd need some finer
method to be really reproducible.
||It gets more accurate the longer the receiver is left in one place.
||Ah. I asked a pilot. Not something you can do in a plane.
||Where do you usually ask a pilot a question?
||Well... they were wearing the uniform.
||A uniform? So they could just have easily been a janitor?
Nice idea [Eugene]. I don't know enough about the subject to get technical but it all seems pretty good. Confusing title though. Didn;t know what to expect but definitely wasn't expecting this.
||Well, it's just that as an editor it's your
job to clean up any continuity breaks in
the movie, and this would help that out
in a major way. Also, recording all of
that information would help you put it
together in the first place. Poorly
labeled footage is an editor's bane. You
need all the notes you can get.