Mr Macaw wrote:

On Tue, 29 Dec 2015 23:53:31 -0000, Roger Merriman wrote:

Alycidon wrote:

On Monday, 28 December 2015 16:53:36 UTC, Mr Macaw wrote:
On Mon, 28 Dec 2015 16:38:39 -0000, Alycidon wrote:

On Monday, 28 December 2015 16:13:51 UTC, Mr Macaw wrote:

Every headlight bulb I've ever seen for the last 30 years has been
55/65W (dual filament). 55 for dip and 65 for full.

Now common sense would make us read that as 55 or 65W OUTPUT if the
bulb is made more efficient. Fitting a 55W LED for example would be
the equivalent of 550W of tungsten, which would be beyond a joke.

I wondered why that car driver told me that my 4000 lumen front bike
light was too bright.

What made you think it wasn't? Have you ever thought to compare it to a
car headlamp?

Yes - a car headlamp is 700 lumen, so my bike light is nearly six times as
bright - he had a point.

which car? My estate has bulbs rated at 1500 lumens dip and 1860 lumen
full beam bulbs, This is a 10 year old car with Halogen bulbs.

one HID bulb can and are 3000lumens plus so plenty of cars around with
6000 and more lumens.

There shouldn't be. The headlamp was always 55W dip 65W full. Having one
brighter than that is dangerous and downright stupid.

stardard bulbs.

watts do not correlate easly to lumens or lux or any other ways of
measuring.

or to put it another way bulbs rated at the same Watts can and will
produce different amount of Lumens.

Roger Merriman