No idea what the ‘right’ answer to that question is Rick. I’ve seen those throw charts before and they didn’t help me much.

But, one thing I noticed while reading the Z4 and panny 900 specs sheets and write ups……..they both have a 2X zoom and both say this makes projector screen distance pretty much a non issue (within reason). I guess you can just use the zoom to get your picture size just right. Which in my case, would be terrific. My situation is similar to yours, I’m not really sure where the hell the thing is going to go, or what size screen I’m going with yet.