How to Fake Motion Control of Miniatures When You Can't Afford a Professional Motion-Control Rig

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I was, for quite a while, trying to make CGI look like miniatures by applying miniature-scale surfaces to the CG models, and adding CG strings and wires, applying handheld camera movement to CG scenes, rendering with shallow depth of field, and so on… this helped give the impression of miniature effects, but after a while I became convinced that it was worth mixing in *real* physical spaceship models to give the scenes the retro feel that I really wanted to aim for.

That led to the challenge of making motion-control effects shots on a tight budget which didn’t allow for an actual motion-control rig. 

in my attempt to make suitably old-fashioned miniature effects for my mockumentary “Zombie Demon Nazis From Uranus” (in which a truly awful movie director tries to make a low-budget sci-fi horror epic, with disastrous results)… I did a few tests with very simple materials:

-a tripod with a maneuverable tripod head.

-a digital camera that can capture stills.

-a miniature model or full-scale scene as the subject of the flyby.

-An application that can do smooth frame blending.

-a ruler and protractor

– a 3d application (I used Lightwave)

Step one: map out a camera move in your 3d application, with a rough wireframe blocking of your real-world scene.  Tweak the camera move until you’re happy with it, then Identify the points (position and rotation) along that move… assume 15 frames for each second of finished shot, or 10-12 if you’re willing to compromise quality a bit.

Step two: Record that flyby in the real world, with stop-motion.  Set your camera carefully to the desired position and rotation settings for each frame.  Capture that frame.  Move on to the next one.  Capture all the frames in the sequence.  Don’t rush it.

Step three: Line up those images in a sequence, on your computer. 

Step four: Interpolate the sequence of frames – in After Effects this is called “Frame Blending” – to stretch its length out by 10%, then another 10%, etc… this is called “stair interpolation” and it generally produces better, more seamless results than simply doing one large frame interpolation.  This blending will achieve two things.  Firstly, it adds a bit of motion blur into the sequence and smooths out slight jitters and inaccuracies in the stop-motion sequence.  Secondly, it allows for you to get 30 frames, or one second, of finished video flyby from every 10-15 source frames captured, with saves you a lot of time carefully positioning and rotating the camera for every frame.

I cannot guarantee perfect results using this technique… but the more precise your positioning of the camera in eah frame the cleaner the final flyby sequence will be.  Keep in mind that you’re less likely to screw things up if you keep the camera moves fairly simple.  Also, note that this, being stop-motion, will be very time-consuming.  But it will allow you to get “motion-control” style shots without a motion control rig.


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