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Operating Cost: Expensive;
Although more efficient than standard incandescent, Halogen sources are still wasteful and still short-lived when compared to sources like fluorescent, LED and High Intensity Discharge (HID).
Color Rendering Index: 100 (great);
Halogen sources also rely on heating filaments to a point of incandescing. These filaments are designed to emit a spectrum that
includes all of the visible wavelengths that objects in our environment may reflect to our eye.
Color Temperature: warm to neutral;
The higher operating temperature of halogen incandescent sources creates light that exhibits a higher color temperature. The filament is heated to about 3000 degrees Kelvin and, therefore, creates a pale yellowish light that we can describe as 3000 Kelvins.
Ballast and Transformer requirements: Some;
Many halogen incandescent sources are engineered to operate at a lower voltage than is commonly delivered to electrical circuits.
These “low voltage” sources require a transformer to “transform”
the electricity from standard line voltage (120 volts in the U.S., 220 volts in much of Europe) to a lower voltage (commonly 12 volts or 24 volts). These transformers can be as small as a candy bar, but must always be considered as they must be installed nearby and must be accessible.
Dimming: Cheap and Easy;
Just like standard incandescent sources, halogen incandescent sources can be dimmed with simple wall box dimmers, which regulate the quantity of electricity delivered through the filament. It is important however to match the dimming equipment to the specific transformer type (electronic or magnetic) if a transformer is in use
Instant on / off: Yes;
Halogen Incandescent filaments heat up to incandescence, and thus give off light nearly instantaneously.
Directability: good to excellent;
One of the most notable by-products of Halogen technology is the ability to build a smaller lamp around a smaller filament. These small lamps are ideal for building into precision reflectors that drive out light in a single direction. The small size is the reason halogen incandescent lamps are so commonly used for accenting, stage lighting, and precision flood lighting. Many halogen incandescent lamps are built with integral optics and reflectors.