TopDog said:
Everyone "says" that flat white is more reflective but how do you know that. There are a lot of myths that live on these boards like aluminum foil causing hot spots etc.
Papa said:
topdog, pick up any textbook on illumination engineering and you'll find the test data. it's not a myth.
Broadly speaking, Papa is correct - but a bit of nuance -
It sort of depends where in the spectrum you measure these things -
Across the
visible spectrum, flat white paint is the best for reflectivity, and most light meters generally give the strongest readings in the visible light spectrum - the HydroFarm light meter - IIRC - is 'tuned' to something like 3000K - "warm white" light rather high in the red spectrum.
So - a - say - 40w bulb @2700K measured 1ft away will give a higher reading than a 40w bulb@7000K measured at the exact same spot/angle of incidence.
Also - from what I understand - mirrored/polished surfaces (not sure about gloss paint tho) like aluminum or dimpled aluminum or even a mirror tend to produce much more reflectivity as you move out of the visible spectrum and into UV.
. . . Food for thought . . .