So yeah, I'm attempting to build a movie theater in my living room. I've got the lcd and taken it apart and it works fine. I just bought an overhead projector with a triplet lens. My main question is dealing with the light source. The overhead does not come with a bulb so I'm going to upgrade the light from a halogen bulb to a metal halide. I'm thinking about going for this bulb
http://www.atlantalightbulbs.com/ecart/10Expand.asp?ProductCode=UHI-S400DDUSHIO
and this balast
http://www.goodmart.com/products/243289.htm
Is this the correct ballast for the bulb?
I've heard this bulb is pretty much the way to go. I have a couple questions though.
1) Since the bulb has 33,000 lumens, would it burn the lcd or something being that bright? Do I NEED a filter (or is it optional)?
2) Is there a way I can buy like a resistor switch or something to control the amount of light output by the bulb so that I wouldn't need it that bright in complete darkness? Or is the 33,000 lumens just fine?
3) Do I just put the metal halide bulb and ballast directly into the overhead projector? Does it have to be placed vertically or horizontally? Does there need to be plenty of room for the bulb (someone told me a minimum of 1 foot) or does the bulb keep relatively cool?
4) Is the wiring for the bulb complex, or can an idiot like me (with no electrical experience) wire the bulb to the ballast?
5) Does the bulb take a while for it to start up? If so how long?
Any help would be greatly appreciated. Thanks in advance.
http://www.atlantalightbulbs.com/ecart/10Expand.asp?ProductCode=UHI-S400DDUSHIO
and this balast
http://www.goodmart.com/products/243289.htm
Is this the correct ballast for the bulb?
I've heard this bulb is pretty much the way to go. I have a couple questions though.
1) Since the bulb has 33,000 lumens, would it burn the lcd or something being that bright? Do I NEED a filter (or is it optional)?
2) Is there a way I can buy like a resistor switch or something to control the amount of light output by the bulb so that I wouldn't need it that bright in complete darkness? Or is the 33,000 lumens just fine?
3) Do I just put the metal halide bulb and ballast directly into the overhead projector? Does it have to be placed vertically or horizontally? Does there need to be plenty of room for the bulb (someone told me a minimum of 1 foot) or does the bulb keep relatively cool?
4) Is the wiring for the bulb complex, or can an idiot like me (with no electrical experience) wire the bulb to the ballast?
5) Does the bulb take a while for it to start up? If so how long?
Any help would be greatly appreciated. Thanks in advance.
thats the bulb I have (havent completed my set up yet). It seems to be a good bulb with goo output, thus why lumenlab (DIY projector) sales site uses them only:https://secure.lumenlab.com/shop/group.php?id=4
1)You may want to look at getting a UV/IR filter as the LCD will get hot and possiblt get damaged from the heat (IR) and fade over time from the UV. Possibly look at getting some clear window tinting designed to block out heat.
2) no idea
3) It would be better to mount the ballast outside of the OHP so it dosnt get to hot (I have mounted mine on the outside of the box). I dont have a foot between my lamp and the fiscal lense, and this seems impossible for most OHPs as the bases are not that high.
The bulb can get hot, so make sure u have some air flow through the unit if possible.
4) no its not simple, u will need to attach a power point connection on the ballast so need to know how to do this correclty, and will also need to safely connect the wires from the ballast to the base in which the lamp screws into. These wires are ont double insolated, so can be breached relatively easily and make what ever breaches them "live" (eg ur whole OHP unit). I had the next door neighbor (electrician) do mine and he was not at all happy with the final job saying he thinks its dangerous 🙁.
5) bulb takes a few seconds to turn on, then gets brighter over abut 1 minute.
Hope this helps.
1)You may want to look at getting a UV/IR filter as the LCD will get hot and possiblt get damaged from the heat (IR) and fade over time from the UV. Possibly look at getting some clear window tinting designed to block out heat.
2) no idea
3) It would be better to mount the ballast outside of the OHP so it dosnt get to hot (I have mounted mine on the outside of the box). I dont have a foot between my lamp and the fiscal lense, and this seems impossible for most OHPs as the bases are not that high.
The bulb can get hot, so make sure u have some air flow through the unit if possible.
4) no its not simple, u will need to attach a power point connection on the ballast so need to know how to do this correclty, and will also need to safely connect the wires from the ballast to the base in which the lamp screws into. These wires are ont double insolated, so can be breached relatively easily and make what ever breaches them "live" (eg ur whole OHP unit). I had the next door neighbor (electrician) do mine and he was not at all happy with the final job saying he thinks its dangerous 🙁.
5) bulb takes a few seconds to turn on, then gets brighter over abut 1 minute.
Hope this helps.
2. No there isn't. Nothing simply anyways. I am still in the "BUILD" stage of my projector so I can't say personally, but the output of your projector is <10% the original light. This have been measured by a few people on here (with lux meters). Most people report around 300 - 1000 lumens output. So that would translate to around 1% - 3% of your original lumens. This is due to:
- Not getting 100% of the light out of the bulb pointing at your LCD
- The Reflector's reflectivity
- Each Fresnel's effeciency
- Each filter's (UV, IR) efficiency
- The percent of light that passes through the LCD (major lumen reduction)
- The projection lens' efficiency
These all add up.
- Not getting 100% of the light out of the bulb pointing at your LCD
- The Reflector's reflectivity
- Each Fresnel's effeciency
- Each filter's (UV, IR) efficiency
- The percent of light that passes through the LCD (major lumen reduction)
- The projection lens' efficiency
These all add up.
thanks
Thanks a ton for all your help so far. Couple more questions though.
What do u mean mount it outside of the overhead projector? Doesn't it have to be inside underneath the lens?
This is most probably the bulb I'll be getting but the only thing I am worried about is wiring it? So, I should get a hold of an electrician to help out with this? Even if I do...will it be safe?
Thanks once again.
Thanks a ton for all your help so far. Couple more questions though.
What do u mean mount it outside of the overhead projector? Doesn't it have to be inside underneath the lens?
This is most probably the bulb I'll be getting but the only thing I am worried about is wiring it? So, I should get a hold of an electrician to help out with this? Even if I do...will it be safe?
Thanks once again.
Also, does anyone know where I can find good ballasts (preferably electronic) for this bulb cheaper than what lumen lab is selling it for.
I'm thinking about going the route of the electronic ballast.
1) Is the electronic ballasts safier than the magnetic ballasts? Just by looking at the pictures, the electronic ones don't look as shady as the magnetic ones.
2) Is there a difference between electronic and magnetic ballasts in wiring them up? Is one easier than the other?
3) Do ballasts have a limited lifespan? If so, about when will it "blow a fuse"?
4) Is there a way to make the setup safer in terms of wiring. Somehow insulating it or insulating the wires more?
What cooljono said got me freaked out about starting a fire or blowing something up. I don't want it to be something dangerous.
My main aim is safety. I'm thinking about buying the ballast and mogul from lumenlab and buying the bulb of the first link I posted ($10 cheaper). Any help would be once again greatly appreciated...this is the last bit of materials I need so then I can finally put it all together. Once I have it done, I will gladly post some pics of my setup.
1) Is the electronic ballasts safier than the magnetic ballasts? Just by looking at the pictures, the electronic ones don't look as shady as the magnetic ones.
2) Is there a difference between electronic and magnetic ballasts in wiring them up? Is one easier than the other?
3) Do ballasts have a limited lifespan? If so, about when will it "blow a fuse"?
4) Is there a way to make the setup safer in terms of wiring. Somehow insulating it or insulating the wires more?
What cooljono said got me freaked out about starting a fire or blowing something up. I don't want it to be something dangerous.
My main aim is safety. I'm thinking about buying the ballast and mogul from lumenlab and buying the bulb of the first link I posted ($10 cheaper). Any help would be once again greatly appreciated...this is the last bit of materials I need so then I can finally put it all together. Once I have it done, I will gladly post some pics of my setup.
lamp & ballast questions
original #3: This lamp is a universal position type, so you can mount it any way you need to. Horizontal will probably fit best, and you will get the most even image if you mount it so the long direction of the lamp matches the long dimension of your LCD. It is a pretty long bulb, so you might have to build a little extension box for your OHP case. You MUST get the center of the lamp arc right where the current lamp filament is.
1) Is the electronic ballasts safier than the magnetic ballasts?
Depends on the electronic ballast: A good one would have short circuit protection, automatic shutdown if the lamp doesn't start, overheating detection, etc. A bad one could be much more dangerous. You can add a 10 amp slow-blow fuse if your OHP doesn't have one. A short would just blow the fuse. The ballasts are not the real safety issue: They don't explode like the lamps sometimes do. (That's why you have to run MH lamps inside an enclosure.)
2) Is there a difference between electronic and magnetic ballasts in wiring them up? Is one easier than the other?
I have the 250 Watt versions of that lamp & ballast (from those sources). The ballast came with a wiring diagram that was pretty easy to follow. If you don't understand safe 120 VAC wiring, have an electrician or handyman do it for you.
3) Do ballasts have a limited lifespan? If so, about when will it "blow a fuse"?
Much longer than a 15000 hour lamp, (which is 10 years of movies!)
4) Is there a way to make the setup safer in terms of wiring. Somehow insulating it or insulating the wires more?
Get somebody else to do it, who has experience! This is not a big issue if you know how to use wire nuts, secure wires with tie straps, etc. This is very standard parking lot / streetlamp technology. How often have you seen one of those in flames?
original #3: This lamp is a universal position type, so you can mount it any way you need to. Horizontal will probably fit best, and you will get the most even image if you mount it so the long direction of the lamp matches the long dimension of your LCD. It is a pretty long bulb, so you might have to build a little extension box for your OHP case. You MUST get the center of the lamp arc right where the current lamp filament is.
1) Is the electronic ballasts safier than the magnetic ballasts?
Depends on the electronic ballast: A good one would have short circuit protection, automatic shutdown if the lamp doesn't start, overheating detection, etc. A bad one could be much more dangerous. You can add a 10 amp slow-blow fuse if your OHP doesn't have one. A short would just blow the fuse. The ballasts are not the real safety issue: They don't explode like the lamps sometimes do. (That's why you have to run MH lamps inside an enclosure.)
2) Is there a difference between electronic and magnetic ballasts in wiring them up? Is one easier than the other?
I have the 250 Watt versions of that lamp & ballast (from those sources). The ballast came with a wiring diagram that was pretty easy to follow. If you don't understand safe 120 VAC wiring, have an electrician or handyman do it for you.
3) Do ballasts have a limited lifespan? If so, about when will it "blow a fuse"?
Much longer than a 15000 hour lamp, (which is 10 years of movies!)
4) Is there a way to make the setup safer in terms of wiring. Somehow insulating it or insulating the wires more?
Get somebody else to do it, who has experience! This is not a big issue if you know how to use wire nuts, secure wires with tie straps, etc. This is very standard parking lot / streetlamp technology. How often have you seen one of those in flames?
heat control
A 400 Watt MH lamp should put out less IR than a 350 Watt tungsten halide lamp (which is a common OHP lamp). Even so, if you want to keep your LCD really cool, you could add a piece of IR filter glass or film between the lamp and the fresnels.
DIYprojectorcompany.com has some that is cheap, and it works pretty well. (But it does cut the visible light by about 20%.)
A 400 Watt MH lamp should put out less IR than a 350 Watt tungsten halide lamp (which is a common OHP lamp). Even so, if you want to keep your LCD really cool, you could add a piece of IR filter glass or film between the lamp and the fresnels.
DIYprojectorcompany.com has some that is cheap, and it works pretty well. (But it does cut the visible light by about 20%.)
Uv Light
I recently read on the forums that Metal Halides produce more UV light than conventional halogen. Is this true? If it is, does this pose a health risk? I understand I'll probably have to put a UV filter glass inbetween the lcd and fresnell so the lcd will not fade but will the UV light still be dangerous?
I recently read on the forums that Metal Halides produce more UV light than conventional halogen. Is this true? If it is, does this pose a health risk? I understand I'll probably have to put a UV filter glass inbetween the lcd and fresnell so the lcd will not fade but will the UV light still be dangerous?
I got the local tinting shops to send me a A4 Sample of their tintings, blocking out 99% UV, 39% heat (IR), and 18 light (havent tried em yet). So if this dosnt block out much light (u can get "specially selective" tint that dosnt), then this will work great.
Also says "fade - 57%" :S? I would have thought blocking out 99% UV would stop fade all together.
If it blocks the UV, then it blocks it, simple as that 🙂, so no it wont be harmful if it is blocked.
Also says "fade - 57%" :S? I would have thought blocking out 99% UV would stop fade all together.
If it blocks the UV, then it blocks it, simple as that 🙂, so no it wont be harmful if it is blocked.
UV health risk
>does [MH lamp UV] pose a health risk?
Most definately YES! If you look directly at an operating MH lamp for more than a second or two, you may damage your eyes. Get enough exposure and you will cause PERMANENT eye injury. You can also get serious sunburn on your hands by working inside your running projector for just a few minutes.
Some lamps have a UV-blocking outer glass, but that only cuts 85-90% of the UV. There is still enough to harm you.
Here is what you should do:
1) Always wear eye protection when your lamp is running exposed. This can be 99.9% UV blocking sunglasses, or welder's goggles. Pay attention to others who might be exposed, like children & pets.
2) If you must make adjustments inside your projector with the lamp running, also wear long sleeves and gloves. Try not to keep your face too close to the lamp for too long.
3) Make a good light-tight enclosure, so the only light coming out is through the LCD and projection lens.
4) Add a UV filter before your LCD. You can buy UV filter sheets for a few dollars, or use a piece of Lexan XL10 with UV blocking coating to support your first fresnel. Either of these will block >99.9% of the UV. Acrylic fresnels will also block a lot of UV, but they will turn yellow over time without UV protection for them!
>does [MH lamp UV] pose a health risk?
Most definately YES! If you look directly at an operating MH lamp for more than a second or two, you may damage your eyes. Get enough exposure and you will cause PERMANENT eye injury. You can also get serious sunburn on your hands by working inside your running projector for just a few minutes.
Some lamps have a UV-blocking outer glass, but that only cuts 85-90% of the UV. There is still enough to harm you.
Here is what you should do:
1) Always wear eye protection when your lamp is running exposed. This can be 99.9% UV blocking sunglasses, or welder's goggles. Pay attention to others who might be exposed, like children & pets.
2) If you must make adjustments inside your projector with the lamp running, also wear long sleeves and gloves. Try not to keep your face too close to the lamp for too long.
3) Make a good light-tight enclosure, so the only light coming out is through the LCD and projection lens.
4) Add a UV filter before your LCD. You can buy UV filter sheets for a few dollars, or use a piece of Lexan XL10 with UV blocking coating to support your first fresnel. Either of these will block >99.9% of the UV. Acrylic fresnels will also block a lot of UV, but they will turn yellow over time without UV protection for them!
lol when i got my metal halide lamp, i plugged it in to test the brightness, and looked at it a little bit to see how bright it got (little bit = maybe 30 seconds haha)
anyway left a brown patch in my vision for ages (like it was burnt into my eyes), and when i closed my eyes, the patch was bright white 😛.
Moral of the story: dont look into the light 😛
I didnt know u could get sun burnt tho 😱 , il be sure to wear protective clothing when im making my adjustments with my recessive piece (if i can figure out how to make sliding slots in a sheet of metal lol).
anyway left a brown patch in my vision for ages (like it was burnt into my eyes), and when i closed my eyes, the patch was bright white 😛.
Moral of the story: dont look into the light 😛
I didnt know u could get sun burnt tho 😱 , il be sure to wear protective clothing when im making my adjustments with my recessive piece (if i can figure out how to make sliding slots in a sheet of metal lol).
slots in sheet metal
There are some sheet metal punches, but those are not cheap.
There is another tool, called a nibbler, that I have seen for <$10 US. You can start at the edge or stick it through a drilled hole, then squeeze the handle to bite off a little rectangle of metal. Then you move it forward into the new space and bite off the next piece, etc. The one I have takes about a 1/4" hole to start but will make a smaller slot.
Another method: Drill a hole at each end of the slot. Then use a Dremel MotoTool thin cutting disk to cut from the middle of the slot toward the holes. These are very good for cutting acrylic fresnels, too. Don't forget your eye protection!
The really primitive method: Drill several holes close together, so you can get a hack saw blade in there. Cut the slot with the hacksaw, then clean it up with a small file.
There are some sheet metal punches, but those are not cheap.
There is another tool, called a nibbler, that I have seen for <$10 US. You can start at the edge or stick it through a drilled hole, then squeeze the handle to bite off a little rectangle of metal. Then you move it forward into the new space and bite off the next piece, etc. The one I have takes about a 1/4" hole to start but will make a smaller slot.
Another method: Drill a hole at each end of the slot. Then use a Dremel MotoTool thin cutting disk to cut from the middle of the slot toward the holes. These are very good for cutting acrylic fresnels, too. Don't forget your eye protection!
The really primitive method: Drill several holes close together, so you can get a hack saw blade in there. Cut the slot with the hacksaw, then clean it up with a small file.
glass shatter
Guy, you mentioned that the bulbs often shatter and that is why you should put the bulb in an enclosure. How does the bulb break? Is it by installing the bulb with your bare hands therefore getting oil on them? Is there any other precautions I can take to minimize shattering the bulb?
Guy, you mentioned that the bulbs often shatter and that is why you should put the bulb in an enclosure. How does the bulb break? Is it by installing the bulb with your bare hands therefore getting oil on them? Is there any other precautions I can take to minimize shattering the bulb?
bulb shattering
Actually, I don't think this type of failure is common. But it does happen, so you have to plan for it. Unless you are one of those crazy fellows who cuts away the outer glass to make a tiny lamp, most failures of the inner glass envelope will be contained by the outer glass. Manufacturers say that their lamps must be used in a fully enclosed fixture, so that they don't get sued when glass fragments rain down on the people below, etc.
If you leave fingerprints on the outer glass, and then run in a sealed fixture without any fan cooling, the fingerprinted area could get much hotter than surrounding clean areas. The difference in expansion could lead to an outer glass failure. But in a DIY projector, you can direct a cool airflow over the whole surface of the outer glass. So I don't think any fingerprinted spots would get that hot.
I suspect that Pre-condensor lens "explosions" cause more damage than lamp explosions. (There are some pretty cool photos of this.) The most common type of lamp failure will involve tiny cracks in the glass where the electrodes pass into the inner envelope. That will make the inner chamber leak into the outer chamber, and the arc just won't start or run.
Actually, I don't think this type of failure is common. But it does happen, so you have to plan for it. Unless you are one of those crazy fellows who cuts away the outer glass to make a tiny lamp, most failures of the inner glass envelope will be contained by the outer glass. Manufacturers say that their lamps must be used in a fully enclosed fixture, so that they don't get sued when glass fragments rain down on the people below, etc.
If you leave fingerprints on the outer glass, and then run in a sealed fixture without any fan cooling, the fingerprinted area could get much hotter than surrounding clean areas. The difference in expansion could lead to an outer glass failure. But in a DIY projector, you can direct a cool airflow over the whole surface of the outer glass. So I don't think any fingerprinted spots would get that hot.
I suspect that Pre-condensor lens "explosions" cause more damage than lamp explosions. (There are some pretty cool photos of this.) The most common type of lamp failure will involve tiny cracks in the glass where the electrodes pass into the inner envelope. That will make the inner chamber leak into the outer chamber, and the arc just won't start or run.
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