Hi VVG,
sorry my scene is heavily approximate and the efficiency value used is wrong.
I have revisited the example scene with Paride that is more expert than me on this argument, and here is the exact values to work with Lumens in c4doctane:
As said, to get the correct light in Octane we need the Watt and Efficiency values. In your Example, the light has 430Watt amd 7.3% of efficiency equal to 0.073 in octane:
Now let's say that we have the only the Lumen value, that, accordingly to this
calculator, for your light should be 430 x 50 lu/W = 21.500 Lumen. To obtain the same light knowing only the Lumens value, we need to use the Lumen value in Power, and 1/683 = 0,001464 in the Efficiency float value:
The Lumens-Watt translation is quite complex and involves also the temperature and the Normalize parameter, but for a general use, this conversion should be more than enough.
Let me know if it works also for you.
Happy rendering,
ciao beppe