Making a DIY Projector. Need help

[MiD]

Hi.

I'm new here, and I'd like to make a DIY projector. I don't have much money now to invest in an LCD projector, so I want to start with a simple one. I have a PC with a 17" flat monitor, which I want to use for that. I read the guides from this site: http://www.diyprojectiontv.8k.com/index.html
and I'd like to make a similiar one. My monitor is placed about 2-3 meters from the wall, and I'd like to project a 60"-70" image on a white wall.
1) Is a magnifying lense fit?
2) How exactly can I calculate the distances - how far the lense should be put? Should I get the monitor nearer? How big should the circle be?
3) What quality can it reach?

Your help would be very appreciated, thanks.

[faithblinded]

I believe you are posting on the wrong forum. This forum is for the discussion of building LCD projectors, not using a fresnel to project a tv on the wall.
You will NEVER have a very bright or crisp projection from the fresnel + TV setup.
Do yourself a favor and spend a little money and make the project worth while. REad through the forums before asking any questions.
And if you're still determined to do a TV + fresnel projector, at least go to the right forums!
http://groups.msn.com/DiyProjectionT...on=get_threads

[loonatron]

A friend of my brother did a DIY LCD projector using some sort of overhead projector setup, but that made his room get too hot!

[MiD]

Thanks for help...

I understand that using LCD + Overhead Projector + Lamps will give much better results than a cheap lense attached to a box - projecting the picture from the monitor, but thus it is [B]cheaper[.B]. And I'm not into spending much money on this project now. Can I get at least watchable-minus picture with that kind of simple projector? I'll do this as an experiment to see how it looks... Then, sometime, hopefully I would build an LCD projector for real use.

And I have a few questions for those of you who already did this:
1) What was the total cost of your DIY projector?
2) Are you happy about the quality?
3) How much electricity does it take?

[Kim Turley]

Hey MiD, that's my site

If you go to it again i've update the guides page. Basically if you check my guide for the cheaper one the picture results were not very bright and blurry

i now have posted my guide for a slightly better one, i suggest buying an lcd screen between 3-7 inches and using that

[Mr.Kh]

Regarding total cost, it's mainly about getting a deal on the LCD. A lighting system can be had for <60 USD (for MH 250W or 400W ballast and bulb) and optics will probably run about 40-100 USD depending on deals you get, and how high quality you want the optics.

Alternately an OHP with a halogen light system, and built in optics can be found for pretty cheap if you look around. Local auctions houses, garage sales, school sales, classifieds, and ebay are usually pretty good sources to hit up if you wanna go that route.


So we're talking ~100USD(on a budget) for pretty much everything you need except the LCD. If you can pickup an LCD for a good price (say 200USD) then your setup is about 300USD without enclosure and screen and stuff.

I have two LCDs I've used for projection, one cost 440CAD the other 50CAD - they're both 15" desktop monitors. One is 4 years old and has a messed up row of pixels 1" from the bottom, but it still leaves me with plenty of room for 16:9 stuff. Look around here to see what people have - and what is the least you want performance wise. And keep your eyes open for deals.

[MiD]

Nice update, Kim Turley.

Still I wanted to see results of the fresnel projector... Like the one in your first guide. If you have pictured of the results of the projecting - I'll be very thankful if you send me, please.

And still one question that bothers me - How much electricity does it take? Is the wattage of the bulb means the electricity that it takes? 400W - about 4 times regular TV!

[jcbklyny]

A general rule of thumb... 1 amp per 100 watts.

Search the forum for some really nice results (a lot better then what I've seen posted in this thread (no offensive).

Your best bet right now for a real nice low cost setup is the Lumenlab projector. (brainchild's thread)

Steps up would be designs from Ace, Cruser and some other real nice designs from a few builders posted here on the board.

www.diybuildergroup.com
Soon!

[ktulu909]

I hate to even admit it,but I did get hit with the fresnel scam,(thats what I think it is at least)but the good news is that is how I found this place(which turned out to be a good thing)

I did the fresnel thing and came out with a 6' blurry,dark and uneven picture that was not watchable.I even tried differnt moniters and plans with the same results.Just save up the money and go the LCD route.As far as power consumption goes,once you see the results,you wont care if it makes your light bill go up by 10 or 15 bucks a month.

And brainchilds site would be a good place to start.The plans are pretty nice and the support is great.

[MiD]

Yeah, Lumenlab projector looks nice... thanks.
How much the bulb Watts is it? And is that right that 400W is about 4 times regular 29" TV? Cause if I'll use it daily for hours it'll take much electricity, which is pretty damn expensive here, relatively. I want to to see if that worths using instead of a regular TV. I understand that it won't work with a weak bulb.

So all I need for that is bulb, lenses (how much can they cost?), and an LCD, and to build it up.