Class : Habitué
Posts : 84
Registered on : 13/01/2010
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I don't remember I have seen such recommendation.
IIRC I saw recommendation that model should be most 1/3 of frame size. The frame size is frame camera can see at distance where clip would be placed.
If you make model too small you can expect some imprecision. That's bcs you will have to amplify your movements through FT and with it you'll amplify those tiny head movements which could easily be ignored with larger model through FT settings.
Sorry about English. I couldn't make simple explanation.