Hi
I have a few comments which might be useful. Although I too do not read German, I do have technical expertise in LED lights; I developed a LED videolight L&M upgrade (www.FTechX.com) that is fully compatible and wet pluggable.
The specs for the Werner LED ring lights are pretty straightforward. The LED R 36 consists of 72 individual white LEDs which collectively emit 1300lumens requiring an input power of 15.6watts ( 10.8V and 1440mA ). With the smallest Werner battery (112mmX62mmX31mm; 10.8V ; 1.6Ah) the burn time at full power should be about one hour. The spec sheet suggests that the 1300 lumen output is equivalent to a 100Watt tungsten lamp. This may be a bit aggressive but not wildly so (assumes 13lumens/watt for tungsten).
One open question is how the 75° angle is determined. The Werner light uses the natural focusing of the LED plastic lens AND appears to have these lenses in direct contact with the water. Under these circumstances, the effect of the plastic lens is reduced. (Try wearing your eyeglasses underwater without a mask!) Werner may have compensated for this effect for the reported measurement but it is not footnoted in their literature. IF the reported measurement was made in air then the angle in water would be significantly increased because the lens will NOT be as strong and the brightness will be weaker because the light is spread out further. I’ll discuss this effect in a future Technology Blog (www.FTechX.com).
I hope these comments help.
Art99
art@FTechX.com