[Boomer]

Also, what is HQI

HQI = Halogen Quartz Iodide, aka, Tungsten Halogen, Quartz Halogen, common out door garage and car headlight.
These are similar to conventional non-halogen incandescent light in that it employs a tungsten filament in a gas-filled, light-transmitting envelope and emits the same type of light.


or

HQI = Mercury Quartz Iodide ( where H is the first letter for Mercury in its chemical symbol, which is Hg. The arc tube is filled with gases (normally argon) along with mercury and other metals (e.g., sodium, lithium, thallium, indium, scandium, Thorium and other "soft silver metals", which give it its K value.) in iodine/halogen salt form, thus the name metal halide (halide refers to mercury content). These are one of the HID lamps, High Intensity Discharge, as are MH, HPS (High Pressure Sodium) and MV (Mercury Vapor). LID's, Low Intensity Discharge, are fluorescent lamps. Both types are a form of Plasma, where incandescent lamps just more or less heat up a filament. In LID lamps the Argon gas produces no light, whereas in HID the gas does produce light. The real purpose behind the gas is to increase internal bulb pressure. In other words, the gas produces or allows more lumens / watt of light. For as gas pressure increases light efficiency increases. and thus less watts of power are need to produce the same amount of light. So, in short, removing the gas from the bulb would give the bulb less light output.

One needs to be careful with terms, as these two lamps are not the same buy ay means. An HQI incandescent puts out no more light than about 20 lumens / watt, whereas a HQI, MH can approach 4 times or more than amount of light.