Good guides, formulas etc for shooting forcedperspective

Gavin Greenwalt

Formula is very simple, scale is proportional to the camera distance of the ‘full size’ object. So if the camera is 20’ and you want ½ scale, put them at 40’. If you want ¾ scale put them at 1 / ¾ = 1.33x as far away.


That applies to all set dimensions relative to camera. If a table edge is 10’ forward 2’ above the camera and 2’ left of camera, the small side of the table would be 20’ 4’ and 4’ respectively.


In a 3D app it’s easier still. Just figure out your scale factor (1/(1/n)). Then scale the “small” half of the set from the camera position.



Gavin Greenwalt

VFX Supervisor – Straightface Studios

Seattle, WA