Panasonic PT-900U on shelf near ceiling?

Discussion in 'Displays' started by MortMO, Jan 23, 2006.

  1. MortMO

    MortMO Auditioning

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    I am having trouble figuring out if the Panasonic PT-900U projector can be placed on a shelf right-side-up near the ceiling. (Ideally with no degradation in image quality.) With my old projector the Panasonic 300U, the projector needed to be placed 3" above the bottom of the screen if right-side-up or 3" below the top of the screen if upside-down in order to keep the image square (without keystone correction.)

    I am not sure about this newer PT-900U projector. It has some vertical lense shift capability that might allow it to be placed right-side-up toward the top of the screen. (On a shelf on the back wall without the need for extra mounting hardware, for example.)
    Anybody know?
     
  2. Sean Laughter

    Sean Laughter Screenwriter

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    As far as I can remember from reading some of the manual (my dad is thinking of getting this projector), the bottom edge of the image is aligned with the bottom of the lens, which can't be changed due to the optics. That's why if the projector is going to be up high you'd generally invert it and ceiling mount it (and then set the settings to invert the image on the panel).

    You MAY be able to lens shift enough to compensate, but I'm not sure, and it would most definately probably be at the extreme end of the shift where you start introducing geometry and image distortions.

    The Panasonic site has the projector "pamphlet" which isn't the whole manual, but at least has the illustration that shows how the image aligns with the lens and and the amount of possible shift, so you should probably hunt it down.
     
  3. Sam Posten

    Sam Posten Moderator
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  4. Angel Pagan

    Angel Pagan Second Unit

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    Posten, you have PM!
     
  5. Jay Mitchosky

    Jay Mitchosky Producer

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    By most accounts the 900's lens shift, already pretty slim at only 13% of height above the screen, begins to bow noticeably before it hits that limit. So for example on an 87" wide/100" diagonal screen the vertical height is around 49", and the maximum available offset above the screen edge is just north of 6". But you would need to stay a fair amount away from that to preserve geometry. Anywhere within the screen boundary is fair game. Also note that if you also use horizontal shift it will limit the available vertical range. If you are interested in getting a projector closer to the ceiling the new Hitachi and Sanyo projectors have more usable shift range and have received similarly excellent reviews.
     

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