I just "tried" it out. I have no clue what focal points are. But I tried a number of things. First, I made a cardboard box to go around the monitor. Then I put the fresnel at the end of the box (45cm long). It could project a 3 inch image to a sheet of paper I was holding in front of it. Then I cut the box in half and put the fresnel on it. It could project a bigger image, but it was really blurry. Then I just said screw the fresnel, and I put an OHP lens in front of it. It projected a fairly big image (3'x4') on my wall, but there was practically no color at all. I'm guessing the fresnel will direct the light straight into the lens and make it all nice and nifty. I wouldn't know. It's 5am.
noodles!
i tried the same thing one year ago, and get the same results!
the fresnel on OHP is doublet, it is two fresnels glued together, so you cant use it for this. try to put ordinary page magnifier with bumpy side towards the tv screen instead of OHP fresnel, combined with OHP magnifier (the one from OHP's arm)!
the reason you are getting pale image is that OHP magnifying lens has small diameter, so there is not enough light passing through it! try to move tv closer to the wall, you will get smaller, but brighter image!
or use the lens from opaque projector, it is basicaly the same as OHP lens, only much bigger, and it will give you much brighter image!
i tried the same thing one year ago, and get the same results!
the fresnel on OHP is doublet, it is two fresnels glued together, so you cant use it for this. try to put ordinary page magnifier with bumpy side towards the tv screen instead of OHP fresnel, combined with OHP magnifier (the one from OHP's arm)!
the reason you are getting pale image is that OHP magnifying lens has small diameter, so there is not enough light passing through it! try to move tv closer to the wall, you will get smaller, but brighter image!
or use the lens from opaque projector, it is basicaly the same as OHP lens, only much bigger, and it will give you much brighter image!
Update: I took my brother's tv 
and I'm using the magnification lens and mirror from my OHP. I'm watching Chasing Amy widescreen on it right now and my guesstimate is that it is 10'x5'. That doesn't sound like the right proportions, but it's still sweet. The picture is still a bit blurry (understood, seeing as how this method is GHETTO!). The blurryness won't be much of a problem when I adjust it and whatnot. I'm still fiddling with the pale thing. The TV is way better than the monitor though.
and I'm using the magnification lens and mirror from my OHP. I'm watching Chasing Amy widescreen on it right now and my guesstimate is that it is 10'x5'. That doesn't sound like the right proportions, but it's still sweet. The picture is still a bit blurry (understood, seeing as how this method is GHETTO!). The blurryness won't be much of a problem when I adjust it and whatnot. I'm still fiddling with the pale thing. The TV is way better than the monitor though.- Status
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