Black Dog LED new Universal series

EXACTLY !

Something quite relevant ..
Blue light ...
Not the same effects like UV ...
But ...
It's another thing to be ~10~25 % of natural light dispersed everywhere (thus 'coming' from everywhere..)
And another thing to be same power percentage ,just coming from above ,in almost perfect cone shaped ," rays "...

Totally different thing ...
Totally different effects of blue light ,there ....

( Yes ,if I remember myshelf correctly LHPCs' of PS II ,are quite sensitive to UVB irradiation ...
Or it was something with the Grana's membrane stacking mechanism ? )

I think the whole system is inactivated by photosensitizers. Shutting down photosystem II not so good for photosynthesis...

Yeap ..From my point of view ,PS II is "low-power ,long -term " system ,in contrast
of PSI which is the "High-power ,short term system " ....

Of course in nature (and almost in all researches / measurements done in/under natural conditions ) ,
both systems have to be in balance ,for maximum PS daily yields ...

They resemble much of higher animal muscle kinetic systems ,with two "kind" of muscle fibers ..
White and red fibers ...(hey ...!!!!.... What a weird a coincidence.... ;-P )
Power vs Stamina/Endurance ..In order for animal to compensate both in i.e walking and running ....

Same with plants ..
Sun rises ,reaches to a zenith ,the starts to set...
During day length ,plant(s) was/were subject to great fluctuations of light power,angle and spectrum ..
Sometimes there are sunny days ,sometimes cloudy ...
Plants have to survive (compensate ...) under all these diverse natural fluctuations of light (and not only ...)
.....
But when it comes to Controlled Environment cultivation (and its pros'n'cons ,freedoms and limitations ) ....

Ohh ..What a mess ...

Try to find the ideal constant lighting ....

stardustsailor said:

Try to find the ideal constant lighting ....

Click to expand...

What that says to me is that you need to have a spectrum that constantly, simultaneously (when the light is on, of course) excites PSI and PSII.

Interesting analogy with muscle fibers. We are all one.....

What that says to me is that you need to have a spectrum that constantly, simultaneously (when the light is on, of course) excites PSI and PSII.

.....
Bingo !
(Again....)

Although more precisely ...:

A bit over-exciting PS II (it can handle that extra red 600-640 nm ,cause of the lower range's absorption,making the 'lazy' system work a tad harder ... ) ....Maybe also a bit more of blue >460 nm & green,would not "hurt " .... And because of protective carotenoids/xanthophylls, always present at appropriate amounts ...

And a bit under-exciting PS I (to make it "work " for longer periods ..i.e 12 hours ..Lower "load" ,longer duty ..
Not so much 640-670 nm "reds" & 430-450 nm "blues "(<=can still grow fine without 'em ,actually ).....Not so high powers of them ...
Although in my new light I do have a great amount of 660 nm red light ..I just wanna see something ....Be sure about it ..Once and for all ...)