In article ,
Dave Gibson wrote:
I recently changed the bulbs in my car headlights. Same size. The
difference in light output was *dramatic*.

I couldn't give a toss about the theory, but the practice means a
great deal.


That's because the old ones are shagged due to the vaporized metal from
the filament blackening the inside of the glass envelope. I am assuming
they are not halogen (or gas discharge for that matter) which do not
suffer such a loss of output with ageing.

I don't know what sort of car you have, but halogen bulbs have been
standard on most for many a year.

Nor were they visibly blackened.

--
*Don't squat with your spurs on *

Dave Plowman London SW 12
RIP Acorn