Buying a light bulb used to be easy

Introduction
Buying a light bulb used to be really easy, but that changed with the arrival of energy-saving models.

It is very hard to buy a quality light bulb. I have often bought from "good" brand-names and got disappointed.

Here is a feature list:


 * Brightness. Unfortunately, the lumen values are not linear, especially from 2,000 Lumen. I don't know the maths. If you can help, please drop me a line. This is the table I have been using for reference:


 * {| class="wikitable"

! title= |Incasdencent Watt ! title= |Lumen ! title= |LED Watt ! title= |Energy-saver Watt ! title= |Halogen Watt
 * 40 W
 * 400 lm
 * 8 W
 * 480 lm
 * 5 W
 * 60 W
 * 720 lm
 * 80 W
 * 1,000 lm
 * 20 W
 * 100 W
 * 1,200 lm
 * 150 W
 * 1,700 lm
 * 1,900 lm
 * 23 W
 * 2,700 lm
 * 28 W
 * 2,800 lm
 * 30 W
 * 3,000-3,250 lm
 * 160 W
 * 200 W
 * 10,000 lm
 * }
 * 2,700 lm
 * 28 W
 * 2,800 lm
 * 30 W
 * 3,000-3,250 lm
 * 160 W
 * 200 W
 * 10,000 lm
 * }
 * 3,000-3,250 lm
 * 160 W
 * 200 W
 * 10,000 lm
 * }
 * 200 W
 * 10,000 lm
 * }
 * }


 * Color temperature. 2700K is best, it yields a yellowish light comparable to the traditional incasdencent light bulbs with a tungsten (wolfram) filament. 3000K might be described as "soft, warm white", but it's a little too cold and you'll notice the difference. Anything over 3000K will be too cold, and the light will turn blueish.
 * Turn-on speed.
 * Lifespan.
 * Cycling endurance.
 * Clear or frosted glass.
 * Noise.
 * Dimmable.
 * Physical robustness.
 * Operating temperature.

Compact fluorescent lamp (CFL)
I am particulary dissatisfied with compact fluorescent lamp (CFL) technology, especially after all the hype.

Its many drawbacks are:
 * Expensive.
 * Slow to turn on.
 * Often last much shorter als advertised, due to low cycling endurance.
 * Noisy. Most CFLs make a humming noise that you may notice in a quiet environment.
 * Cold light colour.
 * Normally not dimmable.
 * The light bulb itself is also ugly.
 * Contain toxic mercury (quicksilver) which complicates their disposal.
 * They turn darker with time.

On the bright side, they consume very little electricity.

LED lamp
LED lamps have a few drawbacks:
 * Expensive.
 * Weak. I just cannot find powerful LED lamps. The ones I see around are too weak for the living room.

They win in every other category.

Halogen lamps
Advantages:
 * Cheap.
 * Fast to turn on.
 * Bright.

Drawbacks:
 * High electricity consumption compared to CFLs or LEDs.
 * They lose a lot of brightness with age (see 'cooking' below).
 * Dimmable, but you often get a hummy noise when dimmed from the power supply.
 * They get very hot, so:
 * They tend to turn darker (they 'cook') with time.
 * If you touch one during operation, you'll get burnt.
 * Careful when cold too. Fingertip oil may make them even hotter and damage them.
 * Some halogen bulbs shed a cold light (colour temp 3000 K or higher).

Fluorescent tubes
Pros:
 * Cheap.
 * Powerful.
 * Consume little electricity.

Cons:
 * Big, long.
 * The starters break down often.
 * Cold colour.
 * Slow to turn on.
 * Poor cycling endurance.
 * Humming noise.
 * Not dimmable.
 * Brittle.