I've been searching for awhile now and cant find anyone who has tried to use Phillips MasterColor® Metal Halide Double-Ended T-7 style Lamps with their setups.
For one, they are used in some commercial projectors, they are made for focused spot lighting (standard Metal Halides... are NOT!) they are only 5" long and produce a MUCH whiter brighter light.
Compare:
- Phillips Mastercolor Pulse Start Metal Halide 400Watts
3900K CCT
66 Color Rendering Index - LOW
31,000 Lumens
No UV Filter, Heat issues
Very Hard To Aim, Focus.
People are saying that 31,000 Lumens are still too dim!
- Phillips Double-Ended T-7 Metal Halide 150Watts
4000K CCT
96 Color Rendering Index!! Much Better!
14,300 Lumens
Built in UV Filter
Much easier to aim, about same price as pulse start bulbs...
Did I mention only 5" Long!
6,000 hours of life isnt as good as 15 or 20,000... but it still better then most if any commercial projector bulb, OHP bulb or Slide projector bulb.
What do you think?
For one, they are used in some commercial projectors, they are made for focused spot lighting (standard Metal Halides... are NOT!) they are only 5" long and produce a MUCH whiter brighter light.
Compare:
- Phillips Mastercolor Pulse Start Metal Halide 400Watts
3900K CCT
66 Color Rendering Index - LOW
31,000 Lumens
No UV Filter, Heat issues
Very Hard To Aim, Focus.
People are saying that 31,000 Lumens are still too dim!
- Phillips Double-Ended T-7 Metal Halide 150Watts
4000K CCT
96 Color Rendering Index!! Much Better!
14,300 Lumens
Built in UV Filter
Much easier to aim, about same price as pulse start bulbs...
Did I mention only 5" Long!
6,000 hours of life isnt as good as 15 or 20,000... but it still better then most if any commercial projector bulb, OHP bulb or Slide projector bulb.
What do you think?
I'm using that bulb at the moment. (The -T version, not the -TS. The -T single ended bulb has a smaller diameter, little less lumen/life, but equally good spectrum).
The color rendering IS much better than that of a std. MH bulb.
The color rendering IS much better than that of a std. MH bulb.
What about the 250W T-8 bulbs. I still don't know how a bulb's lumens translates into a projector's lumens (w/o an LCD).
"I still don't know how a bulb's lumens translates into a projector's lumens (w/o an LCD)."
Without lcd. Its how much of the light from bulb you can direct forward into the path of objectives and ultimatly the Viewed screen. THe losses are decay over distance-conformity of light cone, and the focal lengths of objective. LOTs of loss moving the light to just one area.
With panel. Youhave all the same as above except now you have a lcd which losses ruffly more than 50% of all light =FACT. Two types light. P1 and P2. P1 passes and is seen on screen. P2 ABSORBED as heat. THe more absorbed (ie more light) heat the more it dimms pic and appears washed out. So right there is 50% loss. Add to it the over all dimming from absorbtion-then the fact that glass isnt 100% transmisve. So two glass substrate panels at ???? 97% transmisive and 3% reflective. Thats another 6% loss now where down to 44% light getting through lens. NOW thats if the lens is smack dab against the panel (less than 1") and the objective lens itself is partially reflective. A good estimate isnt acheiveable-to many variables involved. #1 is a small bulb with built in reflector that is tuned to a specific beam size (cone) at a specific distance. Then only the panel is primary prob. Look at a BHB 250 watt or 150watt bulb once you'll seee what I mean about the deseign. Also the cost! WooT!
Without lcd. Its how much of the light from bulb you can direct forward into the path of objectives and ultimatly the Viewed screen. THe losses are decay over distance-conformity of light cone, and the focal lengths of objective. LOTs of loss moving the light to just one area.
With panel. Youhave all the same as above except now you have a lcd which losses ruffly more than 50% of all light =FACT. Two types light. P1 and P2. P1 passes and is seen on screen. P2 ABSORBED as heat. THe more absorbed (ie more light) heat the more it dimms pic and appears washed out. So right there is 50% loss. Add to it the over all dimming from absorbtion-then the fact that glass isnt 100% transmisve. So two glass substrate panels at ???? 97% transmisive and 3% reflective. Thats another 6% loss now where down to 44% light getting through lens. NOW thats if the lens is smack dab against the panel (less than 1") and the objective lens itself is partially reflective. A good estimate isnt acheiveable-to many variables involved. #1 is a small bulb with built in reflector that is tuned to a specific beam size (cone) at a specific distance. Then only the panel is primary prob. Look at a BHB 250 watt or 150watt bulb once you'll seee what I mean about the deseign. Also the cost! WooT!
Judging brightness isn't easy. I'm projecting on a 95" screen made up of epson photo paper (not glossy). I have to change the brightness setting of powerdvd a little to get enough white.
But I wont need to do that when I get a better screen. The photo paper reflects light in all directions (I cant even see any brightness loss when viewing the screen at almost 90 degrees).
I got the bulbs from e-bay germany (8 euro/piece)
Of course I would like to have more lumen, but I'm happy with what I get now, as the picture has tv like colors. And with 'only' 150W you dont need any extra fans.
Edit: When I project a white image with all other lights off I can read a newspaper with just the reflected light. So I guess its bright enough
But I wont need to do that when I get a better screen. The photo paper reflects light in all directions (I cant even see any brightness loss when viewing the screen at almost 90 degrees).
I got the bulbs from e-bay germany (8 euro/piece)
Of course I would like to have more lumen, but I'm happy with what I get now, as the picture has tv like colors. And with 'only' 150W you dont need any extra fans.
Edit: When I project a white image with all other lights off I can read a newspaper with just the reflected light. So I guess its bright enough
Ok, I'm planing on moving over to a much smaller setup so I will either be going double-ended metal halide or using a single ended narrow bulb similar to Akeem's design. Right now I am using an eliptical reflector with a typical large 400w Matel Halide bulb followed by an aspheric lens to widen the beam into a cone shape to cover the fresnel. My question is with the smaller bulbs most people seem to be using sperical reflectors instead of eliptical ones. They also don't seem to be using any type of lens (such as aspheric) to widen the beam. To my knowledge this would create a centre hot spot with dim corners on the screen. Is this correct or am I missing something? So if I use a spherical reflector behind one of these smaller bulbs and use an aspherical lens, will it widen the beam into a cone shape or just pass the light alone without changing the angle? I hope someone has some first hand experince with this because I don't want to waste the money to not get that much of an improvement over my current system.
I'm using the std spherical reflector + condensor lens from my 3M 9850 overhead pj.
Dont blame dark corners only on the optics; the deflection of the light by the fresnel is greater at the corners of the lcd, and lcd's dont like that. (another reason to try to get a small lcd)
Dont blame dark corners only on the optics; the deflection of the light by the fresnel is greater at the corners of the lcd, and lcd's dont like that. (another reason to try to get a small lcd)
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