The XP18 will work best with a 4:3 screen.
The projector has a 16:9 mode to give some of the benefits of anamorphic DVD so you won't lose out on the higher quality transfers.
The throw ratio for this projector is 1.9~2.47:1. For every 1ft of picture width you need between 1.9 and 2.47ft of throw distance. So, a 10ft wide image requires 19~24.7ft of throw.
Check your screen width then calculate the row required, or you can divide the throw by the each number (1.9, 2.47) to work out screen width.
Regards
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Chris Frost
Regional Sales Manager-N.England & Scotland
Owl Video Systems Ltd
www.owl-video.co.uk