MEASURED. NOT MARKETED.
How we measure
A rated figure is what the LEDs can do in a laboratory. A measured figure is what the finished light did on our bench — after the heat, the driver, the lens and the housing take their cut. Both numbers are real. Only one of them is the light you bought. We label which is which.
Three words, one promise
Every figure we publish carries one of three tags. The tag rides the number, so you never have to guess where it came from.
| Tag | What it promises | Carries the verified mark? |
|---|---|---|
| Measured | An instrument reported it, from the complete assembled product. Arithmetic on readings appears as “Derived” (volts × amps from one bench run) or “Calculated from measured” (a system total from separately measured parts) — both trace to a meter. | Yes |
| Rated | Asserted for the product, or true of a component inside it — a manufacturer figure with no Rhino test behind it. Real, but not our reading. | No |
| Test condition | A setting the test ran at — supply voltage, distance. Not a result at all. | No |
Why a datasheet number shrinks
An LED maker’s catalog figure describes one bare emitter on a lab bench at 25 °C — no housing, no lens, no vehicle. Between that number and the trail, physics takes its share at every stage.
1 · LED catalog rating
The 100% mark
What the chip maker measured: one bare emitter, 25 °C, no lens, no housing.
2 · Heat
−10 to 20%
Sealed in a housing on a hot night, the same emitter runs far above 25 °C and gives light back.
3 · Driver
−10 to 20%
The circuit turning vehicle voltage into steady LED current spends some of it as heat.
4 · Lens and optics
−10 to 20%
Light that hits the reflector, the bezel or the inside of the lens never reaches the trail.
5 · Finished light
What is left
What is left is what lights the ground. That is the number worth arguing about.
This is how LED lighting works in general, not a measurement of a Rhino product. The stages multiply rather than add, so the total is not the three numbers summed — industry sources put the overall drop at roughly a quarter to 40%. It is why the biggest number on a box is usually the one furthest from the trail.
The house standard
14.3 V supply — test condition
A running charging system sits near 14 V, not 12 V. Testing at 12.0 V measures a condition your vehicle is rarely in.
13 in read distance — test condition
Repeatable, but not directly comparable with figures published at 1 m, and too close to convert to 1 m reliably.
The instruments
SPS-30DM bench power supply · Handheld digital lux meter (x10 range). A measurement without an instrument is an assertion.
What we don’t measure — and say so
Total lumens
Total lumens need an integrating sphere. We don’t own one, so we won’t call a lumen figure measured. Where we publish one, it wears the Rated tag — a manufacturer figure, stated as such.
Lux is not lumens
Lumens are how much light leaves the light. Lux is how much lands where you pointed it, and it changes with distance — which is why every lux figure we publish carries its distance, and why we don’t convert one into the other.
The line we hold
A spec on a box isn’t a test result. We would rather publish a smaller number we can prove than a bigger one we can’t — and when a figure has no test behind it, the tag says so.
Want the argument behind the product itself? Read The Rhino Difference — or see the tags in use on the rock light comparison and the pod light page.