Greenthumbwannabe
Active Member
lumens measure light output at the source, while candelas measure the light that falls on a surface. As the area of the surface increases, the number of candelas will decrease even as the number of lumens remains constant. So, they measure different things. Were hitting the hood with the 625-630 nm wavelength ideal for the red absorbtion and photosynthesis (660,000 mcd) and the 465-470 nm wave length ideal for the blue absorbtion and photosynthesis ( 2,600,000 mcd) the uv is off the photosynthesis scale with 400-410nm but hey its UV right just like the sun