. Can anyone tell me what the metric equivalent is so Brad can see if he has one that I can buy? And in the event that he doesn't, would anyone else have an Isco lens of this size for me? 
Thanks
Having said that, I would turn around and use Schneider's lens calculator to make sure I was purchasing the right size for my particular application. It's in the Manuals section under "Miscellaneous Programs".
Projection throw, from projector gate to screen.
The scrren height and width.
Calculate yourself the lens size with the lens calculator program and then give the same details to the lens supplier so they can re-calculate to confirm the correct lens size.
Ive known of 2 cinemas who have got new lenses and the projection throw distance was 3 foot out and they ordered the lens, it was of course very wrong!
Darren
And that was after they gave the measurements to a 3rd party.Another rule I ought to add - when measuring the throw recommend people use some kind of laser/some light source measuring device or get the plans for the building out rather than relying on ceiling tiles and a long piece of string!
Have fun at Dolby rob and don't forget my off the back of a lorry MPU 1!
(I dont mind paying really!)
Speak soon
Darren