thanks a lot to all.
Xmichaelmarcondes: no, 10sl about 6h ...no time for me in this works!
X Mattia Sullini: yes, stack studios are a important reference for me...and the 500 dark cloned is a cloned idea!
XHervé: if the cars are all different (colours and tipe) this effect is more obvious...perhaps ....the textures and mapping are very fast...very fast...1 hours for pick the file ( it's modelled and studied to Riccardo Diana my collaborator ) and the render is start! no time for in this works!
X mouse: ciao , non capisco il primo ps! per il secondo ti dico che è un ags standard (non quello di libreria) creato a partire dal libro sui materiali scritto da Tiziano. POsso postartelo senza problemi. ciao carissimo
X Hyperballad: you are more critic for me.

...but you have reason !
Ball trees are 3d objets no clip and the scale is all right...the quality render is not good but these are my faster renders:
ciao ciao
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