Okay, I think I have a basis for my first projector. My goals are very high output, very large output.
I'm thinking of modding an ohp with blowers to keep the lightbox cool.
Light source, HMI 1200W/GS. This is a 1200 watt metal halide lamp with 6000K color temp, 750 hour life, 110,000 lumens and 10mm arc.
Ikea or similiar reflector for the lamp.
Cold mirror above light source to dump short wavelengths. Heavy forced air cooling in this chamber! Relays to shut down illumination if fan power is lost.
LCD panel with decent contrast ratio (300:1 or better).
I plan to elevate the LCD panel above the glass, and perhaps make an aluminum shroud around it. My goal is to have fans on one side that taper down the airflow (increase speed). Perhaps 3 x 4000cfm 110vac box fans:
.--.__
: : `------.--LCD PANEL--------------.
:F: :___________________:
:A: .------"
:N:__'
Will this be enough to keep her cool? Or will she still turn black from the light absorbed??
Issues that still exist: Keystone correction, none for now.
Optics on the overhead, might have to make modifications in order to allow bigger than 12' wide images? Different optics for different occasions?
Ballast for HMI 1200W/GS. Trying to find out if a commercial ballast will work (from warehouse lighting). Found 1500 watt models fairly cheap (magnetic). Could be interchanged with a HMI 2500W/GS setup if I'm feeling dangerous?
Thoughts?
Am I going the wrong way? Is a DLP The only way to handle really high output?
Heat on panel is #1 issue...
I'm thinking of modding an ohp with blowers to keep the lightbox cool.
Light source, HMI 1200W/GS. This is a 1200 watt metal halide lamp with 6000K color temp, 750 hour life, 110,000 lumens and 10mm arc.
Ikea or similiar reflector for the lamp.
Cold mirror above light source to dump short wavelengths. Heavy forced air cooling in this chamber! Relays to shut down illumination if fan power is lost.
LCD panel with decent contrast ratio (300:1 or better).
I plan to elevate the LCD panel above the glass, and perhaps make an aluminum shroud around it. My goal is to have fans on one side that taper down the airflow (increase speed). Perhaps 3 x 4000cfm 110vac box fans:
.--.__
: : `------.--LCD PANEL--------------.
:F: :___________________:
:A: .------"
:N:__'
Will this be enough to keep her cool? Or will she still turn black from the light absorbed??
Issues that still exist: Keystone correction, none for now.
Optics on the overhead, might have to make modifications in order to allow bigger than 12' wide images? Different optics for different occasions?
Ballast for HMI 1200W/GS. Trying to find out if a commercial ballast will work (from warehouse lighting). Found 1500 watt models fairly cheap (magnetic). Could be interchanged with a HMI 2500W/GS setup if I'm feeling dangerous?
Thoughts?
Am I going the wrong way? Is a DLP The only way to handle really high output?
Heat on panel is #1 issue...
wow, are you building a movie theater?
i would definitely consider building a custom enclosure rather than using an ohp, and do you know how loud a 4000 cfm blower will be??? 😱

i would definitely consider building a custom enclosure rather than using an ohp, and do you know how loud a 4000 cfm blower will be??? 😱
Nope. Just would like to build a machine that will jive with my other hobby, lasers.
I'd like to build a unit that I can use:
#1 outdoors, to project large outdoor image. Perhaps in the summer down near the beach.
#2 indoors, rear projected and very large. Perhaps putting together a demo for our geek activities at computer shows and such. Using real rear projection material + black material and a frame made of conduit or some such... 12' wide is probably good enough. 144" wide x 81" high.
My intellabeams use 4000 cfm box fans. They aren't terrible. Much quieter than the blowers on small argon lasers. (Bigger lasers use water cooling, that gets messy. 90amps @ 208vac + water).
The hot mirrors are $$$$. Yowsers.
I'd like to build a unit that I can use:
#1 outdoors, to project large outdoor image. Perhaps in the summer down near the beach.
#2 indoors, rear projected and very large. Perhaps putting together a demo for our geek activities at computer shows and such. Using real rear projection material + black material and a frame made of conduit or some such... 12' wide is probably good enough. 144" wide x 81" high.
My intellabeams use 4000 cfm box fans. They aren't terrible. Much quieter than the blowers on small argon lasers. (Bigger lasers use water cooling, that gets messy. 90amps @ 208vac + water).
The hot mirrors are $$$$. Yowsers.
- Status
- Not open for further replies.