do projectors have adjustable sketch and skew? 
Posted: 31 January 2011 08:33 AM   [ Ignore ]
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surely no projector can be truly perpendicular to its projection surface and will create a skewed image which wuld need to be created.

im trying to work out my throw distance, id like to get an ultra short throw and have the projector directly at the feet of the frame which is holding my acrylic, but the screen will be at 45 degrees from horizontal, can this be corrected on the projector? is it that it can but not as wide as 45 degrees? is it advisable to avoid anything other than a true perpendicular projected image? how does it affect throw distance?

any help anyone could give would be appreciated. if it turns out it cant correct skew then my throw distance will be double and ill have to get a projector with a normal throw.

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Posted: 31 January 2011 08:39 AM   [ Ignore ]   [ # 1 ]
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apparently its called keystoning. is this a feature i need to make sure my projector has or are they all considered to have it? what are the limits of the correcting?

edit: doh, i figured out a mirror held at a slight angle will get rid of the keystone effect. i take it this wont affect focus of the resultant image on the compliant surface?

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Posted: 31 January 2011 02:13 PM   [ Ignore ]   [ # 2 ]
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A mirror will help with that. Not all projectors have keystoning and each one is different in it’s capabilities. You’ll have to read the datasheet for the projector to know the features for each one. However, the best option is to use a mirror and setup the projector at the right angle so there is no keystoning.

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Posted: 02 February 2011 07:01 AM   [ Ignore ]   [ # 3 ]
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right, now im trying to design the projection angle before i buy the projector as it affects throw distance. a factor in my set up is making the whole project area as narrow as possible if you follow me. im designing it for there to be a crowd in front of me so id like to keep these mirrors as close to the frame as possible.

would something like in the picture work? or would my last mirror need to be as close to perpendicular to the screen as possible? and i take it theres no minimum distance a mirror can be to the projector? and the projector can be held upright with no worry about overheating? are there any clever mathematical ways i can work out exactly where my mirror position can be?

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