Cone-beam model: I = Φ/Ω, then E = I/d².
On-axis estimate for a uniform cone: luminous intensity I = Φ / Ω (Ω from full beam angle), then E = I / d² in lux. Real fixtures differ (hotspot, optics, dust); use for studio ballpark planning.
Illuminance: 2.61k lux (2,613.54 lx)
Candela (approx.): 10,454.15 cd
Beam solid angle Ω: 0.4783 sr
Lighting Throw Distance (Lux) helps you cone-beam model: i = φ/ω, then e = i/d². It is commonly used by engineers, lab users, field operators for lux calculator, lumens to lux, beam angle.
Model
Assumes a symmetric cone: solid angle Ω from the full beam width, I = Φ / Ω candela, then E = I / d² lux on axis. Real LEDs, reflectors, and barn doors change the profile; treat output as a ballpark for exposure planning.