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Homebrewed LCD Projectors
pseudofrog writes: "Seems the new thing to do may be to build your own LCD projector. For a couple hundred bucks, some guys are making projectors similar to the professional ones that cost thousands. And it looks pretty simple, too."
Er.. I thought the bulbs alone that powered the projectors cost several hundred dollars? Unless the manufacturers ridiculously over charge for the bulbs, I don't see how an entire system that costs several hundred dollars could compare to a system in which the bulb alone cost that much.
I bought a panel projector from a junk dealer for 10$. This is an older model, 3M 6150, so it's TFT 640x480 18 bit color.
Then I bought a smashed laptop screen for 5$ to get the backlight out.
Put the two together and I got a 15$ LCD monitor, this is fine for messing around with older gear like the Commodore 64, or a PC in 800x600, which the LCD panel can scale.
I'm pretty happy.
CAUTION: Raw LCD panels are very sensitive to static discharge! Use a wrist strap.
My main interest is playing movies on the wall of my living room.
This project looks nice if I can find someone to do it for me that is.
I have a few concerns though.
1) Aren't dvd players using Macrovision to forbid a signal to be output on anything else than a TV? The signal going to a video capture card seems to be a slight problem. Is this a reason why every one in the article is talking about LD and VCD, these two older media not suffering of the Macrovision "virus", er copy protection.
2) Is this really cheap? I mean a dedicated P800 in the living room (cpu speed to cope with descaler complex algorithm)+capture card+LCD panel, etc... I don't even mention the electric bill.
3) Noise level: Getting a Pentium noisy as an air carrier next to a TV and adding the noise of the fan(s) for cooling down the bulb(s), does that meant that I will need to listen to the movie with a pair a noise cancelling headphones?
4) Space: I imagine that the distance from the projector to the screen needs to be consequent. I can't find data regarding the minimum size of a room to use the projector.
I still like the idea though.
PPA, the girl next door.
-- I feel better now. Thanks for asking.
That's one thing that is cool about projectors, they don't devaluate very rapidly (check on ebay for anything 1-2 yrs old) compared to high-end TV. Plus it's not a pain in the ass to move around, plus you can have the size of screen that you want when you have 800+ lumens and good screen. (well obviously the more lumens the better if you're to do 15' diagonal :) )
:).
When I see people buying HDTV TVs at C$5000+ I don't understand why they aren't looking a medium range projector with HDTV support. Okay you don't buy anything under XGA resolution because with all the resampling it'll screw up the quality big time, but still, at 5K you have a nice tv, but at 5K you have a BIG refurb projector that can do both progressive playback of your dvd, give you an image that has easily 4 time the area covered, and best of all, you can play quake at wall size!.
In my case I've been trying to grab a cheap DLP XGA projector for a while, I don't want a 60 inch tv that will be a pain to move around, I want a 90 inch "tv" that I'll be able to plug my computer on it and also have fun watching movies like in the theatre
The replacement lamps are very expensive, but then again, when you look at the "kit" they sell you for 400$, it's basically a specific lamp with specific properties (metal halide, etc etc) at a specific voltage, plus a little crappy plastic holder... there's no optics (you read "lamp module" you'd think it has some collimating lenses or something) and you can buy these same lamps from a third party at 1/5th of the price, and you just have to mount it back on the plastic thing that was attaching the old lamp. If you have to break it, so what, nothing a high-temperature epoxy can't fix.
Anyways, nice to see articles like that, but LCD sucks, DLP is the way to go for video projectors, too bad parts are still expensive, anyone here knows a 3rd party supplier that won't only sell developper kits at 3K$?
--- Metamoderating abusive downgraders since my 300th post.
How about setting up this configuration, not with an LCD screen, but an old CRT monitor? Would the output be too dim? Could you crank the brightness, or would you then loose contrast?
:-)
A guy I know has done this. Yes, it works. Yes, it's too dim to make very much bigger than the CRT.
He used it to project the visual swirly displays things of mp3 players onto the ceiling (dark room) at a party. That's probably the best use for it. Cheap and easy though - all you need is a fresnal lense
Yeah, some of them too simple maybe. Like those plans that were scanned (about half way down the page)... If I'm reading those plans right, he has two 75-100 watt incandescent light bulbs in the box, but not behind the LCD projector - they are in front and to either side. I'm really confused how that is supposed to work. I've seen this sort of thing before from inexperienced people making those upside-down TV & Fresnel setups who think "If I have more light in the box, the image will be brighter" (yeah it will, but so will turning on the lights in the room - and it's obvious why you don't want that).
Anyone got a clue on this? It looks to me like those incandescent bulbs would destroy the image. At the very least the light coming from those bulbs would have to make two trips through each LCD, so the color density would be off. Not to mention the fact that those light bulbs being off to the side would not tend to radiate light that the LCD monitor would direct out of the box. Looks like someone put a lot of work into the design, but it's wrong.
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)