Can I use Automotive Headlamps? Generally no. Most automotive headlamps are Halogen (see above as to why they are not ideal). The reflectors are designed to illuminate a roadway, not an LCD evenly. The only ones semi-suitable are Xenon, but you'd be ditching the lens and reflector to use just the bulb in your projector. They are extremely expensive also. Xenon lamps are also Metal Halide Discharge Lamps and thus have all of the same safety issues as our regular Metal Halide Lamps.

For these Xenon lamps, these are typically around 35W. This is a far cry from the 250-400W that we typically use in these projectors, or even the 150W that many commercial projectors use. If you use one of these, don't expect that you will be able to project a large image and have any kind of brightness left whatsoever.

Sep 18, 2009

There seems to be more discussion around the small Xenon arc lamps again.

Take a look at the wattage and lumen ratings of these lamps. It makes sense that a 35-65W lamp will produce a lot less heat than a 250-400W lamp, given the dramatically reduced amount of power. This does, however, also come with a correspondingly decreased light output.

You would not expect a 7W incandescent christmas lamp to be able to replace a 60W incandescent lamp and give off acceptable light levels, so why would you expect a 35W HID lamp to be able to replace a 250W HID lamp and do the same?

A 7W compact flourescent lamp may be able to replace that 60W incandescent lamp, but that is because it is using a more efficient lighting method. Currently, there is no more efficient method for generating white light than a MH lamp, so to produce the same amount of light, you need that amount of power.

If you can live with a lot less light being projected, then you can use a much lower power light.