First, a disclaimer: it is a
scam. You will not get anything that approaches something that resembles
projection TV.
The plans attempt to turn your television into a magic lantern, which is itself an application of camera obscura.
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| \ / | ^l umop apisdn |
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| /|\ /\ . | _____ | |
|/ | \ ( ). | | W | | |
| | \/ . | |__o__| | |
| / \ . | .|_________| |
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The detailed instructions (available on the net for free! save your $$$) make you build a dark box around your television (turned
upside down!) using cardboard and an opening where a
fresnel lens(sold by the scammer at a heavy markup, of course) is fitted. Once built, the setup is adjusted to project the image on a wall.
Now here are the caveats to this (and why it's a scam):
- This scheme requires the TV brightness turned up all the way. This means a very blurry bloomed image and will dramatically shorten the life of the phosphorus and CRT guns.
- The TV needs to be standing upside down, something it was not designed to do, and results in screwed up linearity (distorted colors).
- Encasing your TV in a box, upside down will adversly affect ventilation making it overheat. (thanks spiregrain)
- Even with the brightness all the way up, the image is very dim, requiring the room to be perfectly dark, daytime viewing is out.
- The fresnel lens used to focus the image is not at all optically perfect (whadya expect for $10) and will severly distort the image.
- The TV tube is curved, so the image will not be projected from the focal point at the edges.
In summary, you get a poorly lit, distorted and blurry "projection TV" which you can only watch during a moonless night.
Well it's not all bad. It could be used semi-effectively for a couple of applications:
- Projecting Winamp or Cthugha visualisations on the ceiling during a party
- Projecting scary pictures on your front window as part of a Halloween night decorations
- (/msg your idea here)
Drinkypoo: you don't have to turn the TV upside down, you can swap wires on the yoke. (The yoke's on you if you break your TV doing that.)