Hey, well its been close to 2 years since i finished my straight shooter PJ. Just recently something crapped out on me, so im tearing it down and rebuilding. This time around im gunna make it a horizontal folded design. Problem is, its been 2 years, so i dont remember all the specs from when i built mine. I want to reuse my lamp, LCD and triplet if possible. The LCD im using is the 10.6 HD LCD, im using an 18" beseler. The biggest thing that i need, is for it to have a 20ft throw. Can someone suggest what fresnels ill need, or direct me to a folded PJ calculator or something? Does anyone know the focal range on the 18" beseler? I cant finish my calculations without knowing that.

18" or 457mm

You can re-use everything, just add a front side mirror. No throw change. It's that easy.