Making An Overhead Projector For The Gp32...


birdofprey

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After something that was said in my last post about "Pluggigng the GP32 into a television" I have decided to build a little OHP so that films / tv episodes etc. can be projected onto a wall for multiple viewers. If anyone could help with this it would be greatly appreciated. Am I corrent in thinkinc I would need an adjustable arm going vertical from the GP32. At the end of that, a square of gass that has an indent (alcove) in the centre to prohect a bigger size. and then off that (which is kept paralell to the screen of the gamepark) i would need a mirror. I know this would project it backwards also but thats ok. Also, do you think this will work for front lit units or only backlit
I'm thinking it will only work with (at least well) with BLU's

Thought it would be a nifty thing to have when going around a mates house. Any idea where I could get the materials would also be a help

Would it be possible to buy an adjustable arm which could have a rubber clip for the gP32, or would it be easier to make a base for the Projector that the gamepark meerey sits on.

Any ideas or suggestions will be greatly appreciated. I start work tonight!
 
I've tried this with my non-FLU and a drawing projector thing and it was too dark and backwards, but It didnt have a light pointed on the screen to fix this. You could rig up some kind of mirror to fix the backwardsness like at the eyedoctors with the letters projected on the mirror thus correcting the backwardsness.
 
I hate to be negative, but I seriously doubt that the GP32 front light would have enough light to project the image onto a wall or anything - as an experiment, try holding your GP32 next to a wall and see if there is much light reflected...

OHP's usually have fairly power lamps in them to project the image - which is why they are so noisy (big cooling fans)...
 
Lol, you get it working, tell me ;) I've had interest in a project like this for about half a year (finally mentioned it in your other post) Might not work too good with a BLU, but all of us practically have screens with a reflective silver lining underneath, so it'll reflect the light real good!

Yes, it would need extra light and probably a cooling fan so you don't cook your gp32 but it could be done!
 
When I get home I can explain better. Its very dark but you can tell its the screen, ill take a picture of the projector. It would not be worth it to buy a projector just for GP32. It was bought for art purposes.
 
heh...this is actually a fun idea...for movies and such...

about a year ago i was working on a projector....i actually got it to put images on the wall..such as something i printed on a normal sheet of paper...light reflected off of the object and onto a mirror into a lens...

you will need a TON of light to do this tho... i'd say about 20 of the brightest white leds you can get your hands on...

you will need to have your lens adjustable so that you can get the picture good and focused...

it isn't that crazy of an idea...you would have to have your frontlight turned off...other than that it would work nicely....
 
Sounds quite possible if one would use one of those new type overhead projectors (no mirrors). Those projectors have a build in rgb monitor output which can be connected to a beamer or monitor. Can't find one using google right now, but we have one at work so i'm gonna see what brand and type it is tomorrow.
 
I remember someone trying to do this before but connect it up to a TV. The problem is that the GP32 is not capable of outputting in 640x480, so even with interpolation it'll look horrible.
 
I built a Fresnel lens projector for a small TV I have. It worked, except that I used cut cardboard so I couldn't get the focus quite right. You need wood if you want it to work.

the problem is:

A. You need a BRIGHT image. PC monitors aren't even bright enough, you need a TV.

B. Gaming projectors are difficult because you need mirrors to flip the screen back to normal.

C. You have to build a complete box around the screen, which would make a GP32 rather unwieldy even if the screen was bright enough.

But hey, if you want to connect your GP32 to a TV and build a projection box for your TV, I have plans that use either a fresnel lens or a magnifying glass lens, and I'll email them to anyone who wants them.
 
I remember someone trying to do this before but connect it up to a TV. The problem is that the GP32 is not capable of outputting in 640x480, so even with interpolation it'll look horrible.
The projector should give a 'natural' interpolation.

320x240 isn't bad really. ...Was plenty for us in the good ol' days. You young'un's today? tsk!
 
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Yeah, build an assembly made out of cardboard to fit flush to the surface of the GP32 around the screen area. Take a fresnal lens, cut to size, and place it inside the cardboard enclosure in a way that you can adjust it to focus the image. If I recall correctly, the ridges on the lens need to face towards the screen, but I'm not sure, I'd have to look it up. Then, attatch a mirror (big enough to reflect the entire image) at the open end of the cardboard assembly, angling outwards so that the image is reflected out and ends up upright. You can buy kits on e-bay for doing this, including instructions, usually under the title "100 inch projection TV" or something like that. Search it up.
 
jmetal88 sounds like he knows what he's talking about :) However one word of warning about those ebay kits - sometimes they are just links to publically available kit manuals or they send you the free kit manual through email.
 
jmetal88 sounds like he knows what he's talking about :) However one word of warning about those ebay kits - sometimes they are just links to publically available kit manuals or they send you the free kit manual through email.
AND they just sell you a page magnifier that you can buy at almost any office store....

it works like a charm! if you had enuff light, a page magnifier would work well...nice and lightweight...

but you would also need a mirror ;)
 
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