How to calculate the foot candle requirements?

I am struggling to translate the various lumens of different chandelier fixtures I am considering for a dining room into incandescent equivalents or just figuring out if the lumens are sufficient. How you did do the final calculation of the over 12,000 lumens that you got to use the size of the room and the ceiling height?

The basic calculation formula for estimating lumen needs is:

​Illuminance (footcandles) = light output (lumens) / surface area (square feet)

Additionally, we factor in the reflectivity of the walls (linear adjustment based on reflectivity %) and the ceiling height. Ceiling height is accounted for on a logarithmic basis (base 10) and an adjustment factor of 20.

​If you're looking for a more simplified way to verify the outputs of the calculator, we would recommend setting the wall reflectance to 100% and the ceiling height to 8 ft.

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LED bulbs (General)

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