Your are kind of talking apples to oranges here.
Plasma TV vrs a front Projector with a screen.
There is a big difference here in room requirements.
A front projection HAS to have controlled room lighting to be able to see the image and a GOOD screen.
The Optoma H77 DLP has only 900 ANSI lumens which is not a lot, will need a dark room for best results.
So if you don't have a dark room get the plasma. John
I can't make up my mind on purchasing one of these Video Items: Panasonic TH42-PX500U Plasma TV or Optoma H77 DLP Projector, Does anybody have any suggestions? Thanks

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