Not sure if this is the right place, but couldn't find any subforum that really seemed to fit my question.
I just got a request from a friend who wants me to take a landscape photograph for her that will be hung up in her winery. It will be printed on semi transparent paper mounted behind a plexiglass wall and then back lit. She mentioned that people should be able to get fairly close to it and should still be able to make out details then. I currently have a 7d and figured for this I would need at least 150dpi which would result in 12 photographs. (24 if you take into consideration that images need to overlap and that you should have some room on all sides for final composition) If I go to 300dpi (which I think would be overkill) we're talking about 44 (or rather 88) photographs. (Unless my calculations are wrong of course)
Does anybody have experience with prints this large (and printed on transparent paper) Is 150dpi reasonable, way too little or too much after all because you'll never get this much detail on non-photo paper anyways?