home made huge projection tvs ???

[backups121]

hi,
was looking through ebay and came across alot of people selling plans and lens to make ur own projection screen. it costs around 7 quid for it posted and all. stuff arrived last week i got a big magnifing lens and a cd rom which contains plans on how to make the projector screen. it looks quite straight forward to do all it involves really is inclosing a small tv in a box and using the lens to project onto the wall. At the min i ave a 36inch toshiba tv but im already a bit pissed off and want something really big. just wondering has any1 else built one of these projectors or know of any1 who has got results wiv em? just asking cause im curious 2 see if any1 has had success before i go and build mine.
Cheers:beer:

[tursa12]

sounds interesting let us know how it goes

[gooner]

Wouldn't bother mate, trust me. Better to sell your rear projection and pay the difference for a projector, they only cost £700 these days

[freakit]

the image will be projected through the lens onto the wall backwards. Don't plan on watching a movies with subtitles or you will be lost. Unless you can read from right to left.

[Neo]

This does work, you just have to align it all, but quality is not the best. Aligning takes more time to do than to actually build it.



PROJECTION TV PLANS

PURCHASE THE FOLLOWING ITEMS:

1. magnifying glass (at least 2 inches, 5 inches works best)
**note: don't get the magnifying glass that has the magnifying spot on it, you'll know it when you see it** (They are also selling these lenses on eBay for $1.99)

2. Duct tape (black duct tape works best) 2 inches wide or more

3. Cardboard or presentation board (the presentation board used for school projects works best)
**note: you can buy black presentation board, and you may not need the spray paint, I didn't**

4. Flat black spray paint

5. Pencil or marker

6. Exacto razor blade or box cutter (scissors can be used, but razor blades are much easier)

7. Mirror (about 5 inches in diameter)

LET'S ASSEMBLE THE PROJECTOR

First: Measure the vertical and horizontal distance of the television screen. DO NOT measure the entire tv, the projector attaches to the screen.

Second: Cut your pieces. Using 32 inches for the length the width should be the measurement of our screeen. For instance if your screen measures 25 x 24, then you will cut two pieces to measure 25 x 32, and two pieces to measure 24 x 32. Make sure that your cut is straight.

Third: Cut your slider. This is the piece that will be used to focus your projector. Getting the proper focus could take a few minutes. Cut this piece using the measurements of the sides widths. In the example a 25 x 24 screen was used, so this slider should measure 25 x 24.

Fourth: Remove the lens from the magnifying glass and place directly in the center of the slider. Trace around the lens and carefully cut out the circle. The lens should fit in the hole snug.

Fifth: Paint the projector and slider using the black paint, both sides. It may require more than one coat of paint. Do not paint over the lens. Take the lens out for this step.

Sixth: Tape the sides and top and bottom together, tape to make sure no light shines through. At this point you should have a box with four sides.

Seventh: Insert the slider about halfway into the box. The slider should stand up and should not allow any light to pass through the edges. Light should only pass through the lens.

Eigth: Unplug your tv and turn it upside down, attach projector to tv using tape or whatever you want to use. No light should pass through the edges. Light should only pass through the lens.

Ninth: Turn on your tv. The room should be as dark as possible. Adjust the slider in and out until the picture is focused (this will take a few minutes). Remember, the farther the projector is from the wall, the bigger the picture will be.

Finally: If your projected image is reverse place the mirror at a 45 degree angle in front of the lens. This will also allow you to adjust the height of the picture. After the projector is focused cut the excess of the projector in front of the slider off.

[smokafatty]

I wouldn't bother using a tv setup as the quality is not worth the time making the projector.

If you want a decent DIY projector you will have to use a lcd screen and a light source.

Here (http://www.louisville.edu/%7Ewchall01/diyprojector/pictures.htm) is an example of a budget projector that is pretty decent.

But if you really want to do it right, you need a setup like this:
http://gwidijanto.fcpages.com/projector1lens.xls
(you will probably have to cut and paste the link in a new browser window)

[backups121]

the tv i ave at the moment isnt a projection screen it a 100hz tv and it cost 1800 quid wouldnt sell it to buy a projector just like the idea of trying to build 1 of these, also if the film did have subtitles u could still project it onto the wall cause the lens only projects the image upside down not back to front so u just ave to turn the tv that u r projecting upside down. im gona give it a go anyway and see wat happens- check this site out looks pretty good www.bigscreenprojection.com (http://www.bigscreenprojection.com)

[Templar]

I bought one of those fresnel lens "projector kits" like 25 years ago! Ah the memories, and oh how it sucked!

[bonzai]

is this for real or has everybody just seen the episode of still game that was on bbc scotland recently?????

[lockhart]

thats where i seen it lol on STILL GAME and i thought i might give it a try

[vcdburn]

It's a lens that is about 8X10

you cut a circle in the peice of cardboard

Make a cardboard cover for your tv, looks like this when your done.

|------
| | \
| | \
| (tv) | \
| | \ <---- Cardboard tunnel
| | |
| | | <---- Put lens here
| | |
| | /
| | /
| | /<---- Cardboard tunnel
| | /
-------/

Did I mention you need to FLIP your TV upside down? This is to make your picture right side up.

It's crap!!

[vcdburn]

I should have looked at the diagram on the execel sheet first ... It's better then mine.

[LiquidMercury]

I bought one of those fresnel lens "projector kits" like 25 years ago! Ah the memories, and oh how it sucked!
:laugh:

[JuMpMaN6235]

with the TV's out now they are much better quality then they were 25 years ago... so maybe it wont suck so much... if your going to do this use a quality Magnifying Glass and a very good quality TV... also a Large White projection screen would help