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Hs10 Sideshot Warning!!

Discussion in 'Projectors, Screens & Video Processors' started by ebury, Feb 19, 2003.

  1. ebury

    ebury
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    hi all, can anyone tell me that the side shot technology actualy works on the hs10.I bought one with the intention of using from about 1.2 meters to the left from the screen centre and no matter how much ive tried it is impossible to get a satisfactory picture(the image on 82" screen shrinks to about 60" and the rest of the screen is filled with a grey shadow!!!)In the manual supplied with the hs10 it clearly shows two images that put the projector too the left of the screen,which has too be either misleading or a con!!!.For my screen size and distance between projector the manual states you can only offset the hs10 by 200mm.How the hell does that translate to a side shot picture??????.All i can do now is put the projector on a table at the back of the room,every time i want to watch a film(i cant put on ceilling in the centre because of hanging lights!!!)should i send back or are all supposed side shot projectors just a CON?Sorry to go on but i did expect a better picture using side shot when the picture when centred is as good as ive seen ever in this price range!:mad:
     
  2. gothmog

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    I suspect a con :mad:

    The same happens with my AE-300 when any digital keystone is applied, the screen shrinks about 5% or so.

    Fortunately I don't have to use it, but it is well off that such a feature can be implied to have any equivalance to proper lens shift optics like the Sanyo-Z1.

    It's an evil spec-sheet filler like digital zoom on cameras.

    -- Jon
     
  3. Comer

    Comer
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    I'm not too sure about this but I would assume that the screen would have to shrink when you use keystone correction. Lets say u are projecting down from the ceiling and as a result the bottom of your image is splayed out wider than the top. But another distortion is that it is longer, vertically, than it should be. So using keystone correction to bring the bottom of the image to the same width as the top should (if u want a propper shaped image) also make the image smaller vertically. Maybe I'm way off the mark here or perhaps you are talking about something else completely.

    Conor
     
  4. gothmog

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    bah, you're no fun ;)

    And right of course, I think what makes it bad on the AE300 is that the first 'notch' of correction is huge and therefore the image shrinks a lot as soon as you start using keystone.

    I dread to think how much vertical resolution you lose in the process. Using H+V digital keystone is going to slay picture quality. Altho the HS10 should be considerably better as it has more resolution to lose :p

    -- Jon
     
  5. LV426

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    Everything described here is to be expected. When you put a PJ off-centre to the screen (in any direction) then, all other things being equal, you will get a trapezoid shaped image. That's just simple optical physics.

    Digital keystone correction addresses this by making the image on the LCD panels trapzoid in shape (in the opposite direction). This can only be done by using a trapezoid-shaped part of the LCD panel ie less than the whole.

    So, your PJ still throws a rectangular image, which appears trapeziod on the screen. But the active part of the thrown image (the picture) is trapezoid in the opoosite direction and thus appears rectangular on the screen.

    It's NOT a con. It's a useful feature for people who can't place their PJ in the optimal position. But it DOES degrade the image and DOES cause a trapezoid shaped overspill area which isn't completely black (because LCDs can't do black completely).

    As for light fittings - replace them with recessed downlighters.
     
  6. a_b

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    The projector has to be a fair distance from the screen, ideally somewhere closer to the maximum specified distance for the size of the screen. Then it is easy to use zoom to adjust for picture "shrinking".

    It is indeed a useful feature, and I still use it with HS1. The light overspill is compensated well by the black border of the screen. As for quality - as always, exchanging some quality for convenience.
     
  7. vulkan75

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    i too had this trouble and spent the best part of two nights sorting it out.

    you cant prevent the light spill(grey) cos the side shot only adjusts the image not the whole frame.

    distances are crucial the manual is quite complex on this but doing the math does pay off.

    alternativley purchase a short throw lens..:rolleyes:
     
  8. gingercat

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    I would suggest making some sort of a mask to place infront of (not attached to) your lens to block out the grey areas resulting from the keystone correction. Don't put it too close to the lens or you may get some nasty heat build-up.
     
  9. LV426

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    Wouldn't work well placed near the lens as its edges would be out of focus on the screen. Better to mask the screen itself with, say, a painted black border, or similar.
     

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