This only answers half the question. I posed mine differently and I was careful to define what I wanted; I wanted to get 800 PPfD or more @50% or better efficiency over my trellis panel that's four feet across by six feet tall, for a total of twenty four square feet on a flat plane... in my case, a flat vertical plane.
This defines size, shape and light intensity. In addition, it helps define the LED lighting approach because I wanted somewhat higher efficiency. I wasn't willing to settle for forty something percent efficiency- but sixty plus was too expensive.
At this point, it was relatively straightforward to find the best combination suited to filling the above requirements. I ended up with a design that uses four CXB3590 chips and a 200W driver (forgot the Meanwell part number) to light a 2'x3' area. That's exactly one quarter of my trellis, so four of them will do a great job if evenly lighting my trellis panel for 800W. If that doesn't sound like much power savings over using HID lighting, consider that in order to get the same PPfD on my canopy with HPS, I'd need easily twice the wattage.
I hope this also helps; begin with the end goal firmly in mind. If people complain about the goal being vague, use that as an invitation to better define what that end goal looks like.
you are planning on lighting a 4 foot by 6 foot trellis with 800 watts spread evenly over the trellis.i grow this way now like you do but with hps.
i am planning to light a 4 foot tall by 4 foot wide area with the light being applied from all sides towards each other.i am not sure on how to calculate how many watts due to the high power and penetration of the cob.
do i calculate by square footage of each side of the plant like a flat grow and consider there is 4 sides to the plant?now my number of cobs just quadrupled
most people growing horizontally have any where from 2 foot tall plants to 6 foot tall plants indoors.
if the plants grow great from root to top using these formulas for lighting from one direction,do i use the same number of cobs spread evenly on all sides?
if some people can chime in on how tall their plants are and how good the plant is at the bottom will help give me a better idea on how many chips i need to order for this test.
my idea for this is based on the krusty method where you have 4 plants surrounded with 5 1000 watt hps so each plant is always lit up from 3 sides.
i think i will order 20 cxb3590 and try one plant with 2 on each side for a total of 400 watts and 1 plant with three on each side.