BobCajun
Well-Known Member
Oh, okay, so you can get about 93 lm per LED at max power. You'd need about 75 per sq ft at that power then. So a 300 LED board could light a 2'x2' area at high intensity. That's pretty good. Four of them for a 4'x4' tent.You can get way more than 9000 lm from a QB. 65ma is not a normal current for Samsung lm561C. They show that number to make the LEDs look exceptional. I'm not sure anyone runs them that soft. You ever see a led light bulb that's over 100 lms a watt in warm white? QBs can cover a 2x2+ space. If you wanted to run really close and create a solid QB I would recommend drastically lower diode density. 75 LEDs per square ft? If you where really chasing efficiency 150 per square ft would net you really high umol/j figures.
And you're right about the A19 LED bulbs never being over 100 lm/w. Weird. Maybe it's just an AC rectified circuit, like the AC COBs. Or maybe that's how much they put out with the diffusers on. They're a lot brighter when you cut them off. Or is it just because they're cheapo LEDs? The bulbs are made by Osram/Sylvania, so how crappy could they be?