new project

This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
In the last pages of the thread " of Projector?"
Ace said:
"For about $100 - $350 your can buy a whole dlp projector with decent specs, all you have to do then is just strip the light system (can help you there, ive sorted that out including the hardest resisance method), and retrofit it out with a cdm-t in an ellipsidal reflector, the brightness will be brighter then the original bulb"

Last year mathias said the same thing

problems in commercial projector:

1. we will need a good reflector for the tiny LCD (or DLP chip)
2. In the box of commercial projector there isn't enough space for the lamp/reflector.
3. with a strong lamp the case of the commercial projector might melt.

Maybe Ace_3000 can get a good picture from small 150W cdm-t pic but we human will need stronger lamp.

So for the first problem we will put a stronger lamp
For the 2 3 problems:
we can take apart the commercial projector and to build a new box So we can put a bigger lamp/reflector.

mathias and Ace_3000 what about this lamp?
(thank you Guy Grotke)
no, not that lamp!

The Ushio retrofit lamps are okay for a completely DIY projector, with a large diameter projection lens.

But that lamp has an arc length of about 25 mm, and most of the light comes from the ends of the arc. If you try to use that lamp with a commercial projector that has optics designed for a 5 mm arc length, you won't get much of the light where it has to go to make it to the screen. (Most of it will be on paths that don't even get it into the lens!)

The best position for such a lamp would be with one end of the arc at the reflector's first focal point, so you would lose about 75% of the light right at the reflector.

If you want to replace a short-arc lamp in a commercial projector, you will need to use another lamp with about the same size arc and the same or more lumens output. I think those all cost at least 5 times the price of a Ushio retrofit lamp. The good news is that there are some available now with lifetimes over 1000 hours.

And NO, you can't do anything to make a big lamp arc "seem" smaller, other than just block the light from part of the arc.
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.