opinions on $300 XGA projector?

[Kris Petro]

To save a few $, I am considering building a homemade XGA projector system
using an overhead projector and an LCD monitor. Details are here:

http://www.denguru.com/2004/11/13/supersize_your_tv_for_/

My purpose would be to use it in a high school classroom, for ppt
presentations and the like. Since the total cost would still be around
$300, I am curious as to how well/ how poorly this device would work.
Unfortunately, my budget limits me to such a possibility, which is great if
it works, but I just want to be sure before I spend the dollars. Any
advice, tips, etc would be appreciated.

Thanks,
Kris

 

[martin griffith]

To save a few $, I am considering building a homemade XGA projector system
using an overhead projector and an LCD monitor. Details are here:

http://www.denguru.com/2004/11/13/supersize_your_tv_for_/

My purpose would be to use it in a high school classroom, for ppt
presentations and the like. Since the total cost would still be around
$300, I am curious as to how well/ how poorly this device would work.
Unfortunately, my budget limits me to such a possibility, which is great if
it works, but I just want to be sure before I spend the dollars. Any
advice, tips, etc would be appreciated.

Thanks,
Kris

I looke at some of these DIY projectors some time ago, just out of
interest, and what the seem to miss out in the spec is that you
apparently Really Need a Dark Room (TM) bad fitting blinds on the
windoze will ruin the presentation.

Sorry, No URLS are left in my thing that keeps my URLs


martin

 

[John_H]

To save a few $, I am considering building a homemade XGA projector system
using an overhead projector and an LCD monitor. Details are here:

http://www.denguru.com/2004/11/13/supersize_your_tv_for_/

My purpose would be to use it in a high school classroom, for ppt
presentations and the like. Since the total cost would still be around
$300, I am curious as to how well/ how poorly this device would work.
Unfortunately, my budget limits me to such a possibility, which is great if
it works, but I just want to be sure before I spend the dollars. Any
advice, tips, etc would be appreciated.

Thanks,
Kris

Overhead projector LCD displays used to be pretty common. One thing you
*must* do is manage the temperature the device is exposed to. The
worsth thing about those old contraptions was their marginal lifetime
because of the thermal degredation. How many times do you want to
replace the LCD each year?

 

[Ian Stirling]

To save a few $, I am considering building a homemade XGA projector system
using an overhead projector and an LCD monitor. Details are here:

Ideally, the polarisers on a colour LCD will absorb 1/2 the incoming
light, and 2/3 will get blocked by hitting the wrong colour of
pixel.

Or 1/6th of the icoming light will get through.
And that's optimal, it's never going to be that good.

 

[Joel Kolstad]

Or 1/6th of the icoming light will get through.
And that's optimal, it's never going to be that good.

I suspect that's why, even though the article starst with a "3500 ANSI lumens"
over-head projector, the end result isn't as bright as a commercial video
projector of equal ratings, and they end up neeidng a darkish room.

Hmm... no wonder the lesser-priced micro-mirror based projectors use color
wheels!