Build Your Own SLA/SLS

I trying to design the frame for my printer but won't have a projector until I'm back in the states next month. Using the numbers from the manual for the projector I calculated that for a 192mm x 108mm image the projector needs to be 21.6 cm away from the build plate and the base needs be offset from the bottom edge (relative to the projector) of the image by 3cm. Can anyone confirm that these numbers are close to correct?

the distance could be right, but for the offset from the bottom edge you need to consider that the projector is projecting "up". The bottom edge of the projection is roughtly at about the same height as the center of the lens (no matter how far you go), which might be about 3cm.
i'd rather confirm with a cad drawing, which i don't have right now :/

thanks, those numbers come from a cad drawing I did using the diagrams in the manual which has measurements from the surface the projector sits on.