Imagine a light source 10 feet high above the canopy and a second one 1 foot above a canopy.
Both lights are bright enough to lay down 1000PPF at the canopy.
How much light is left 1 foot down from that, in the case of each light source?
How much light is left 2 feet down from that ?
Yeah! Much more with the light source 10ft above of course. But these light source have to be much more powerful to reach the same 1000μmol/s/m2 as the light source 1ft above.
When you hang a 5 double row and a 10 single row lamp next to another and measure the brightness at the same heights there is no magical higher reading with the 5 double row's. It's the same amount of photons only more spreaded, but at the bottom of the tent it would be equally bright. A double row strip is just like two single row strips next to another.
Only if you get close to 2" to the DR stripes, you get higher numbers, but for that your gaps between the stripes are bigger, so that everything is equalized at the end.
Let's try it from a different viewing angle.
Better penetration can be achieved by generating as much light as possible but with little to no shadows on the illuminated surface. Correct?
Leaves in the shade of other leaves get less light. Correct?
To reduce the shadows, so what is more suitable? One or more light sources? Yepp! The more the better!
As more light sources produce less shadows, more distant shoots get more light "because they are not overshadowed". Diffusity is the keyword!
In fact, it is diffused light that reaches down to the ground in greenhouses. Greenhouse growers have an 8% higher harvest on average when using diffused foils and that although these foils allow only 85-92% light transmission. This means that in spite of 8-15% less intensity, they harvest 8% more, like a gardener without foils, only because of the diffused light.
