LED Dive Lights
Canister vs Handheld Lights
Heraclitus, a Greek philosopher (about 500 BC), wrote "Nothing endures but change."
LED technology has advanced to the point where inexpensive backup lights are as bright or brighter than previous generation primary lights, plus LED is dramatically more reliable and much lower power consumption than the older filament bulb technologies. Today this means the main operational difference between a backup light and primary light is the burn time. With advancement in rechargeable battery technologies even the form factor of the large battery canister is being questioned... do you really need more than 4 hours of burn time at full power? Frankly, just because you can pack more than double or triple the burn time and lumen output in the same form factor as the older can lights doesn't mean it makes sense for many exploration divers. Most dives are shorter than two hours and some lights can be so bright that the back-scatter actually diminishes the divers night vision to effectively reduce apparent visibility. Thus a new class of lower cost technical dive light has begun to supplant the corded light head and battery canister form factor of the past... the handheld primary light seems to be the future.