My understanding, lumen is flood and candella/lux is throw. We have two lights, both are a 1000 lumens.
The EC4 and
the EC4S. The EC4 is a thrower and due to the reflector design, the EC4S is a flooder. Out the front, the EC4 has more candella. The point, I look at both lumen and candella, not just one or the other.
Candella as cd is a description of throw.
Lumens are not an indicator of flood or throw, but of total output.
IE: BEAM ANGLE and charactoristics will determine, given size of the spot...and for example, the more lumens, the more throw generally, for a given beam angle.
Wattage, etc, while what people are used to for incandescent lights, is mostly meaningless for an LED.
IE: An LED with higher wattage might be dimmer, or brighter, or the same, depending upon the LED.
A household light bulb uses the SAME VOLTS, and frequency...such as 60 hz and 120 v....and might have a 15 - 20 amp fuse on the circuit, but only use a fraction of it.
The LED doesn't. It might use more volts or less, depending upon the circuit being buck, boost, etc, and using how many cells, of 1.2 to 4.2 volts for example each, and the cells might be in series, or in parallel, or partially in both, and with different resistors to adjust the amps, and so on.
Comparing the brightness of LED by wattage would only be useful if, like light bulbs, they all shared the same source power...and circuitry etc.
Of course, light bulbs of the same wattage can have very different outputs anyway..
.its only measuring what its using up, not what its putting out.
A light bulb is really just putting out heat, with a small percentage of visible light for example, so for the same watt light bulb, one might put out a little more light and a little less heat.
Better miles per gallon doesn't mean a vehical is slower or faster, just that its using less gas to get there.
A motorcycle might get better mpg than a prius, but might also blow its doors off for example.