You're welcome to your opinion but I don't agree with this statement.
AFAIK, light output from any source is usually measured in lumen and that is the only accurate method of comparison between different bulbs or light sources.
What the salespeople leave out, is that beam angle, colour temperature, and reflectivity of the destination are just as important parameters to consider.
Whereas lux is the resultant illumination of the surface or destination at a specific distance and is based on all the above.
If we were to use lux to qualify different bulbs, it would be necessary to perform a myriad of qualifications on the value, such as beam angle, colour temperature, and a specific distance to the destination, from the light source, etc.
It would be necessary to qualify that the resultant lux from 'the said bulb' will be X based on a specific reflector or projector housing because each housing will have a different result.
I do agree that marketing does not provide sufficient details and will always make an effort to distort and manipulate the facts to make their product appear better than another.
I do agree that subjectively, we're not too likely to see much difference between 9,000 & 10,000 lumen and that the higher output is a newer release of the product but...
As you mentioned, there are 2 bulbs. So, now the increase is 2000 lumen, and even though the resultant lux will not be much more, it is still more.
If the cost is almost identical and it is an updated version, why would I choose the older model with less light output?
Light output is usually measured in lumens, and lux is the result at the surface or destination, at a specific distance.
The following article has a clear definition of the difference between lumen and lux.
Easy to understand graphic explaining the difference between lux and lumens as well as a conversion calculator.
www.waveformlighting.com
These are a couple of quotes from the above link.
The difference between lux and lumens by definition
The core difference can be summarized as follows:
- Lux is a measure of illuminance, the total amount of light that falls on a surface
- Lumens is a measure of luminous flux, the total amount of light emitted in all directions.
Lux is a measure of how much light falls on a particular surface and can be the result of multiple light bulbs and even daylight mixed in.
On the other hand, lumens is important for knowing how much light a single light source emits. This is useful for comparing the total amount of light a bulb emits, but depending on its light distribution and space size, whether it is "enough" for a space or task cannot necessarily be determined.
YMMV
. Well, you may say that I'm welcome to my opinion. The only problem with that statement is the fact that it's not just an opinion, but it was actually a fact. Using lumens to measure the output of light for a vehicle is pointless. And your whole theory of everything being measured with lumens is actually incorrect. Technically it's not incorrect. It is used but it's used wrongly. It is used as a marketing gimmick only. Actual light output to actually be useful for us can only be measured with locks. Lumens is pointless and your definition that you posted explains that perfectly. Lumens only measures the amount of light directed in all directions which is no good to us. We need the amount of light that hits a surface. The surface directly in front of us doesn't matter about the light that goes up into the sky or over into the bush where you don't need it. You only need directly in front and slightly off to each side. So I'll hold true to the statement that using lumens for measurement is pointless. It is strictly a marketing gimmick. Most of these companies do not have the proper tools to measure the actual locks because of the fact that that is actually going to be slightly different in every headlight housing that the lights are inserted in. Where is lumens can be blindly stated because they're just grasping the measurement at a 3-ft or a 10 ft distance directly emitted off the bulb. It does not take into account the headlight housing. I have retrofitted headlights and multiple vehicles for approximately the last 12 years less now as I don't really have the time for it. Just my own personal vehicle. I'll stick to the facts that I gather from the multiple headlight retrofit companies that I source parts from. One in particular, that is probably the most well-known and provides the majority of my supplies, the retrofit source aka the TRS store. If you want to find some actual valid facts on measuring light output, there's a good starting source.
