LED Lighting Question

My question is about different spectrums of LED lights. If I have a 6500k and a 2700k light each at 200 watts....does the plant see the separate spectrums, meaning the high blue and high red separately or does the plant see the reduced averages on both sides of the spectrum and see it it like my light meter at about 4600k?
 

II69II

Active Member
If I had to guess the lower light temp isnt gonna subtract from the higher one. Itll prolly register at 6500k with an added 2700k. But I am now gonna educate myself on the matter.
 

Merlin1147

Well-Known Member
Interesting question. Technically no they won’t see the average but from a growing perspective it will work. Both those lights are full spectrum, meaning they are radiating over a wide range of wavelengths on a curve. The peak of the 2700K is in the longer red wavelengths and the 6500K in the blues. A 4600K light would have peak radiation somewhere in the middle. To get a close ball park of the peak wavelength output: Peak = 3,000,000 / K. So the peak wavelength output of the 2700K light is 3,000,000/2700K = 1111 nm, near IR and the 6500K peak is at 461. So blue. Try googling Wien’s Law.
 

Lockedin

Well-Known Member
Not saying anything on the science - bro or otherwise. Just saying I grew really nice plants under my current setup.

I'm running two 6 bar racks from https://growdaddyleds.com/ in my 4x8 flowering tent.
Each rack has four 2,700k and two 6,500k bars - 480w total.
Planning to add two additional bars to each rack for more even coverage.

edit - as for spectrums; Here's what I've gleaned - I'm definitely not above being wrong...
I've read elsewhere that most white LEDs are mostly yellow, with a phosphor coating to "tune" the spectrum to the appropriate Kelvin
Some "white" LEDs use a small COB consisting of RGB diodes.
IMHO - the RGB units may have a small edge with the green diodes penetrating leaves better than R or (most) B.

 
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II69II

Active Member
Interesting question. Technically no they won’t see the average but from a growing perspective it will work. Both those lights are full spectrum, meaning they are radiating over a wide range of wavelengths on a curve. The peak of the 2700K is in the longer red wavelengths and the 6500K in the blues. A 4600K light would have peak radiation somewhere in the middle. To get a close ball park of the peak wavelength output: Peak = 3,000,000 / K. So the peak wavelength output of the 2700K light is 3,000,000/2700K = 1111 nm, near IR and the 6500K peak is at 461. So blue. Try googling Wien’s Law.
Oh dang I dont have to educate myself, thank you. Im gonna peep this Wiens Law
 
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