nice explanation pipe! it really does make all the difference too!
the easiest and least light restrictive direction for the light to come out of that bulb is from the sides. looking at one while its on from the tip there really isnt that much light shining in your face, however once you look at the side, it really hurts your eyes! that alone should tell you there is a tremendous difference in the amount of light output just by turning it. you will lose lots of light that will just be bouncing around the sides of your grow spot. definitely mount it horizontally!
Peace!
the easiest and least light restrictive direction for the light to come out of that bulb is from the sides. looking at one while its on from the tip there really isnt that much light shining in your face, however once you look at the side, it really hurts your eyes! that alone should tell you there is a tremendous difference in the amount of light output just by turning it. you will lose lots of light that will just be bouncing around the sides of your grow spot. definitely mount it horizontally!
Peace!