Double fixtures = Double Par?

[Soylent Wrasse]

Something I've been curious about, but have never found a straight answer:

If I run two LED Fixtures that each produce 250 Par at 6" does that give me 500 par or just two separate sources of 250? I'm not a math guy but I think I remember reading that it would fall somewhere in between the single and the double amounts.

Anyone have some links/examples?

The brand of fixture doesn't matter, just trying to understand the maths behind it.

Thanks.

 

[Keithcorals]

If you get overlap just right you can get double the par

 

[Soylent Wrasse]

So without actually measuring (no par meter) it would be a fair guess to give it ~50% or so bump? Obviously lenses will make a difference, but if they are wide 100-150 degree optics the spread should be better. Thanks for your answer!

 

[Soylent Wrasse]

Here is a very simple mock up. I'd guess a par meter will tell me the truth.

 

[SantaMonicaHelp]

Sounds like a great idea! Nothing stops you from having 4 fixtures and quadrupling the par right?

 

[Keithcorals]

For the sake of simple math if the two fixtures had a par of half of what they do at the center so 125 at the center of where the two overlap you would have a par of 250 between the two fixtures and a more even par number between the two fixtures. This is hard to get a good picture of without knowing what fixtures and there is a limit to how close you can place fixtures next to each other so you would get to a point where even with a ton of fixtures you would only be spreading the area covered by light and not increasing par