Quote:
Originally Posted by mrhasan
Try touching the heatsink; I dare you 
The thing is, both LEDs and MH "runs" hot but MH "dissipates" heat (and light) omnidirectionally (since its a round bulb) and cannot be fitted with heat sink to take away the heat. On the other hand, LEDs dissipates heat bidirectionally but emits light unidirectionally and so can be fitted with heat sink on the opposite side with heat sink to take away the heat. And hence the "runs cooler" market hype  If some sort of technology comes which allows MH to be fitted with heat, that market tag line is going to be buried. |
They are not hot at all. Even after running at 100% for hours. I have fixtures with built in fans and other ones without them.