i m starting a new projector project and ordered a sharp 1500 lcd panel , and while i was at walmart i found a cool touch halogen work light for 25 bucks it produces 6000 lumens and has a 300 watt long life bulb , i also have a ton of old computer fans i so i could run a fan also , what you guys think
I don't know, but from what i've heard, halogen lighting produces a lower color temperature light (more yellow than white), and also runs hotter. I think that's why most everyone that wants a solid bright, white light uses a Metal Halide bulb that has a higher color temp, and runs cooler.
worklamps don't work so well for projection
Those worklamps don't work very well for a couple of reasons. They are not point sources, which is essential for LCD projectors. Also, the reflector that is in that is a diffuser flood reflector, so light scatters out of the worklamp in all directions. We need a more consistent angle of incident light than those can provide. And finally the reason that those lamps are ultimately not going to work well is because they have a super low color temperature of about 2900k. A light source should be between about 3,200k and 9,000k.
If you'd like an inexpensive light source, then find a broken overhead projector and rip the lamp holder and transistor out of it. Most lamp holders in the older OHPs are Gy5.3's I think, which means that you can use an assortment of small halogen bulbs that have their own reflector built in. If you have a lamp holder but no transistor, then you can use any of the 120v halogens that they carry at hardware stores. I recommend using at least a 300 watt bulb. A 410 watt FXL-5 bulb would be the best of the inexpensive halgoens I think, but that bulb uses an 84v power supply, which means that you have to use the transistor that comes inside of the OHPs that can use them.
If anyone wants it, I have a really nice 400 watt metal halide bulb and ballast that I'd sell for $45 bucks. The ballast is an electronic ballast instead of a magnetic one, so it runs in near silence. I have that ballast, a couple of mogul sockets, and 2 bulbs.
Those worklamps don't work very well for a couple of reasons. They are not point sources, which is essential for LCD projectors. Also, the reflector that is in that is a diffuser flood reflector, so light scatters out of the worklamp in all directions. We need a more consistent angle of incident light than those can provide. And finally the reason that those lamps are ultimately not going to work well is because they have a super low color temperature of about 2900k. A light source should be between about 3,200k and 9,000k.
If you'd like an inexpensive light source, then find a broken overhead projector and rip the lamp holder and transistor out of it. Most lamp holders in the older OHPs are Gy5.3's I think, which means that you can use an assortment of small halogen bulbs that have their own reflector built in. If you have a lamp holder but no transistor, then you can use any of the 120v halogens that they carry at hardware stores. I recommend using at least a 300 watt bulb. A 410 watt FXL-5 bulb would be the best of the inexpensive halgoens I think, but that bulb uses an 84v power supply, which means that you have to use the transistor that comes inside of the OHPs that can use them.
If anyone wants it, I have a really nice 400 watt metal halide bulb and ballast that I'd sell for $45 bucks. The ballast is an electronic ballast instead of a magnetic one, so it runs in near silence. I have that ballast, a couple of mogul sockets, and 2 bulbs.
Re: worklamps don't work so well for projection
Aw man...when was that posted, did you sell taht item yet? Plz say no!
diylabs said:
Aw man...when was that posted, did you sell taht item yet? Plz say no!
Yes, I have sold that particular unit, although I can get more if there is any interest in them. 400 watt kits are still much better (in my opinion) than using most types of halogen setups, although I prefer the ultra slim 250 watt kits because they are more easily used with a reflector and condenser lens. This is because most of the 400 watt bulbs are too large to be used with an adequate reflector (must be roughly equal to or smaller than the projection lens diameter) or with a good condenser (too hard to place a lens that close the light source).
That 400 watt ballast and bulb sounds nice. If you get more how much will they cost? If it's anywhere around what you mentioned I'll definetly be picking one up(With shipping I payed $40 for a four FXL-5 bulbs...). A few questions:
How much are the bulbs, and how long do they last?
How big is the ballast(approximately)?
I have plenty of space where my projector is setup, and might consider building a whole new lower compartment for my OHP to house the 400 watt bulb, and just using the optics from the OHP.
How much are the bulbs, and how long do they last?
How big is the ballast(approximately)?
I have plenty of space where my projector is setup, and might consider building a whole new lower compartment for my OHP to house the 400 watt bulb, and just using the optics from the OHP.
The 400 watt ballasts are relatively inexpensive compared to the 250 watt kits that I sell because they use core and coil ballasts instead of electronic ballasts. What this means for DIYers is that the 400 watt kits make a lot of humming (that's what core and coil ballasts do). I have 1 more ballast, base, and bulb kit that I'll sell for $30 since it's used. In the future, I can probably get new kits for roughly half the price of the 250 watt kit that I sell, but I'm not sure if I'll end up carrying them or not.
Most 400 watt lamps are roughly the shape and size of a football, so they are typically not able to be used with a suitable reflector or condenser lens, which is why I got rid of my setup - it's not easy to collect all of the light from the lamp. Having said that, you can buy skinnier bulbs for the 400 watt m59 ballasts that are small enough to be used with a small reflector, but I don't think it would work quite as well, and these bulbs are considerably more expensive than average bulbs (roughly $75 per bulb). This makes the cost of a 400 watt system with skinny bulb about $125. I highly recommend simply spending the extra $25 to get the 250 watt kit so that you can have the full benefit of an electronic ballast with no humming, a projector that is much lighter (the eBallast only weighs 3 pounds compared to the 15 pounds of those other ballasts), and also you'll be able to make your projector brighter this way since you can easily make an inexpensive reflector for it and then add a condenser lens later when the become available.
Most 400 watt lamps are roughly the shape and size of a football, so they are typically not able to be used with a suitable reflector or condenser lens, which is why I got rid of my setup - it's not easy to collect all of the light from the lamp. Having said that, you can buy skinnier bulbs for the 400 watt m59 ballasts that are small enough to be used with a small reflector, but I don't think it would work quite as well, and these bulbs are considerably more expensive than average bulbs (roughly $75 per bulb). This makes the cost of a 400 watt system with skinny bulb about $125. I highly recommend simply spending the extra $25 to get the 250 watt kit so that you can have the full benefit of an electronic ballast with no humming, a projector that is much lighter (the eBallast only weighs 3 pounds compared to the 15 pounds of those other ballasts), and also you'll be able to make your projector brighter this way since you can easily make an inexpensive reflector for it and then add a condenser lens later when the become available.
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