Photoinhibition in MJ?

I have grown coral in a reef tank, and understand that they can get 'too much' light so to speak, and wonder if they same can be said for the MJ plant?

What I mean is, you give them (corals) 10hrs. of light, but they don't use all that light (maybe 5 of those hours they are using), at a certain point, it is no longer benefitting the coral. Basically, wasted light.

I guess what i'm really trying to get at, is running a (for example sake) say a 400w HPS bulb 12 hours during flowering necessary? Could you run it, say, 6 hours and have some lower light running the other 6hrs? Would this significatly decrease yield? Anyone know of any research done on this topic?

I know this is a little more advanced topic, but something I find interesting.

It would decrease yield dramatically. 400 watter can't compare to the sun.

Yes, there is such a thing as too much light for cannabis. Whether you think of it in terms of "Doing physical damage to the plant" or in terms of "Diminishing Returns" (wasted electricity).

There comes a point where adding more light to a given space will not produce proportional benefits in yield or quality - that is just wasteful! At some point the "Radient Heat" becomes so intense that damage is done. Of course these levels are fairely high and "common sense" acts as a pretty good guide.

50-75 watts of good, "HID Lighting" per square foot is a reasonable "Safety Zone". Much less than that and you suffer from "too weak", much more than that and you better know what you are doing!