Designing large graphics in scale

Hello,

I am designing a tradeshow booth graphic where the final print size will be 89 1/2" H x 156 1/2" W. My original image is 500 dpi and is 9 1/2" H x 9 1/2" W. The specs require this to be in 1/4 scale which is 22 1/2" H x 39" W. If I start out with 500 dpi and expand the image to the spec sizes, how do I figure out what my final dpi will be.

Also, If I design an image in photoshop and I want the final image to be 300 dpi print quality and the final size to be about 35" diameter and I created it at 1200 dpi in 1/4 scale, will it be the same quality as designing it in full scale at 300 dpi.

Sorry if this all sounds confusing, but any help, tutorials, reference books or anything would be greatly appreciated.

Thanks in advance,

Cris

That seems to make sense... I've never really thought about how they make large banner ads look so crisp.

But I suppose you won't be right next to this graphic - you will be at least a couple of metres away, so any it will probably look quite clear anyway...