Building a projector

[imported_TopCat]

I'm looking to build a projector so that I can play games, watch movies with it, etc. I'm wondering if I use a 1280x1024 display as the basis, how much of a hit to image quality due to scaling am I looking at for 720p content? 1080i? I have a monitor but no way to currently test for myself with nothing that outputs HD to RGB or DVI save my video card. Maybe somone can suggest a manner in which I can experiment and see for myself? Any help would be appreciated. Also, would it be better to go with a small LCD TV display that might also have component inputs or do those not come at small sizes and high resolutions?

 

[NoStateofMind]

This is a good article on Building A Projector Hope this is what you were looking for

 

[YOyoYOhowsDAjello]

With a 1280x1024 display you could get 720p going, but 1080i native would require a 1920x1080 display.

Check out http://www.lumenlab.com/ and the forum there.

 

[imported_TopCat]

Thanks for the replies.

The Tom's Guide doesn't really address the issue of scaling and image quality. I'm also going to build the unit from scratch using a metal halide bulb instead of an overhead projector with a halogen lamp. I'd rather a bulb last 6K - 10K hours than 50 - 70.

The Lumenlab forums that might be able to answer my question also cost $20 just to view. I'd like to exhaust the cheaper options, first.

 

[LungExpansion]

Do your bulb research and google a project called BEAMER. Its much smaller.

A friend of mine built one and were building a second one now with a lot different parts than the one from lumenlab. The lumenlab is good for the beginner getting the concepts however its picture will have a wash look to it because of the bulb being used.

Dont do Toms hardware that is a joke the stray light produced from that wont produce a nice final image because it will light up the room too much. you want a very closed project with no stray light.

Here is Mike's page bug him to get with the project already.
http://www.njdevil.com/funprojects.htm

 

[destrekor]

Originally posted by: LungExpansion
Do your bulb research and google a project called BEAMER. Its much smaller.

A friend of mine built one and were building a second one now with a lot different parts than the one from lumenlab. The lumenlab is good for the beginner getting the concepts however its picture will have a wash look to it because of the bulb being used.

Dont do Toms hardware that is a joke the stray light produced from that wont produce a nice final image because it will light up the room too much. you want a very closed project with no stray light.

Here is Mike's page bug him to get with the project already.
http://www.njdevil.com/funprojects.htm

provide us with a link for this 'beamer' project... personally i think it looks good.. but if you can prove to me the beamer is better, please do.. im interested in a project like this too, at least at some point in time... i googled 'beamer projector' and didn't find anything but german stuff

 

[YOyoYOhowsDAjello]

Originally posted by: TopCat
Thanks for the replies.

The Tom's Guide doesn't really address the issue of scaling and image quality. I'm also going to build the unit from scratch using a metal halide bulb instead of an overhead projector with a halogen lamp. I'd rather a bulb last 6K - 10K hours than 50 - 70.

The Lumenlab forums that might be able to answer my question also cost $20 just to view. I'd like to exhaust the cheaper options, first.

Whoops, didn't know you had to pay. I've never gone there as I went with a retail projector.

You can get quite the deal on a refurb if you find one. Infocus 4805s were going to $500 a while ago.

 

[xtknight]

Sounds sweet, but if the reason is money I'm not sure you could save much or not. If the reason is experimentation, then more power to you.

 

[imported_TopCat]

http://www.diyprojectorcompany.com/

That's a good site with free plans and instructions for the beginner. They even sell the parts as a whole or subkits if one is inclined.

I figure if I'm getting an SXGA screen that doesn't allow image centering or aspect ratio scaling, that the picture would appear blurry and stretched, which is what I want to avoid. Guess I'll have to keep on looking for others that already addressed similar issues in their projector builds.

 

[YOyoYOhowsDAjello]

If you're hooking up to a computer, you should have decent options for how the display is used for resolution and such.

Check out the HTPC area of AVSforum (this one is free)

 

[imported_TopCat]

Originally posted by: YOyoYOhowsDAjello
If you're hooking up to a computer, you should have decent options for how the display is used for resolution and such.

Check out the HTPC area of AVSforum (this one is free)

I want to go the computerless route, to faciliate ease of use. Yeah, with a computer makes things quite a bit easier.

I did, however, find this device linked from that DIY forum:
http://www.viewsonic.com/products/tvent...inment/tvvideoprocessors/nextvisionn6/

Looks like a nice external video processor. It can take SD and HD inputs, and outputs up to SXGA. $199, which isn't so bad. One downside is it only outputs to analog which is understandable since adding in a signal converter would jack up the price of the box.

 

[LungExpansion]

This one specifically.
http://www.diyprojectorcompany.com/designs/pico_at_a_glance_en.htm

Also look on www.diyaudio.com they have a home projector group. One of the best on the web.

My buddy uses a projector panel that is rated at a mere 33fps and 1024x768 resolution and at 120" projected DVD's look fantastic. DVD is 720x480 which is quite surprising considering how large the screen is. I dont believe you need any resolution greater it will still look great.

Mike said look for a bulb with a CRI of 85 or better. The ones they sell all over the place are low like 65 which cause a grayish wash. We are building my beamer with a bulb that has a CRI of 93. Its made by philips. The bulb cost me something like 65.00 which is twice the cost of a cheaper one but hey they last like 10,000 hours. He says it will produce a much more accurate color scale with no wash. All the stuff is at his place so I cant give model number but I will be there tommorow for a little while.

 

[LungExpansion]

Here is a good example of a beamer. Pretty much a straight firing projector. This is about as easy as they get. About the minimal amount of parts (Note No Front Side Mirrors)

http://www.dv-memories.com/Projector/