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Projecting down at an angle

Discussion in 'Projectors, Screens & Video Processors' started by common, Dec 15, 2003.

  1. common

    common
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    I need to tilt my HS10 down quite a bit as it's going to sit on top of a book shelf.

    The manual mentions a max of only 15 degrees - any idea why ?
     
  2. LV426

    LV426
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    When you project 'downwards' - all other things being equal, you will get a trapezoid-shaped image. The top will be narrower than the bottom.

    For this reason, PJs have an internal adjustment that re-shapes the image to compensate (eg. in this case, making the bottom narrower so as to restore a rectangular shape as it should be). Depending on the PJ this may be provided by a mechanical adjustment of the lens and/or a digital adjustment of the image on the (eg) LCD panels. This is known as keystone adjustment.

    The reason for the limit is because this is the maximum extent to which the projector supports such an adjustment. In other words, go more than 15 degrees and you won't be able to obtain a properly rectangular image.

    Digital keystone adjustments degrade the image somewhat and are best avoided if feasible. However, if it IS unavoidable - it is better than having an incorrectly-shaped image.
     
  3. common

    common
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    Many thanks for the reply

    My other option is to mount it within the book case, it would have front and rear ventillation but none at the side - any issues ?
     
  4. LV426

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    Have you considered mounting the PJ upside down? I'm assuming (because I'm not familiar with the HS10) that it supports this. And it may well mean that you don't need to tilt it at all, or as much.

    Ventilation: you can never have too much. A build up of heat in the unit will hugely shorten its life. At best, the lamp will die sooner. At worst, the heat build up may damage other components. You must ensure that the cooling fan, inlets, and outlets, all have a free airflow.
     

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