CFL question

[jdakin95]

So im getting 2 150 watt cfl's actual wattage and one in 2700k and the other is 6500k can i use both of these at the same time or do i have to use them one at a time like 6500k for veg and 2700k for flower hoping i can use them both together obviously for the extra lumens. sorry for sounding like a total noob

[redaaron]

yo jdakin95. yes, you can use both. i would start with one bulb for the first two weeks the 6500k and then add the other for the rest of the veg. 300w should do just fine for a couple small plants. :thumbsup:

[TheBudReaper]

When you say actual wattage 2700. You are incorrect. That is the number on the light spectrum that the lights produce. I think 2700 is more on the blue side.

When buying a bulb or light system. Check watts ( amount of energy used to power the item ) Lumens ( the amount of light said item will produce ) then light spectrum. Most lights are 2700k, 5000k, 6500k. 2700k is good for veg while 6500k is better suited for the flowering stage.
:thumbsup:Good luck:rasta:

[headshake]

When you say actual wattage 2700. You are incorrect. That is the number on the light spectrum that the lights produce. I think 2700 is more on the blue side.

When buying a bulb or light system. Check watts ( amount of energy used to power the item ) Lumens ( the amount of light said item will produce ) then light spectrum. Most lights are 2700k, 5000k, 6500k. 2700k is good for veg while 6500k is better suited for the flowering stage.
:thumbsup:Good luck:rasta:

he said 150W actual wattage. the K (short for 1000) behind the 2700 (2700K) indicates the color spectrum. 2700K is actually in the red spectrum, 6500K is in the blue spectrum. 2700K is better for flower, 6500K for veg.

using watts is not the best idea. watts are merely the consumption of power. this doesn't take into account the efficiency of the bulb.


-shake

[WhiteTux]

he said 150W actual wattage. the K (short for 1000) behind the 2700 (2700K) indicates the color spectrum. 2700K is actually in the red spectrum, 6500K is in the blue spectrum. 2700K is better for flower, 6500K for veg.

using watts is not the best idea. watts are merely the consumption of power. this doesn't take into account the efficiency of the bulb.


-shake

The K is actually for Kelvin. It measures the temperature of the light emited from the bulb.. And, higher kelvin values mean less lumen output from the bulb.

[headshake]

The K is actually for Kelvin. It measures the temperature of the light emited from the bulb.. And, higher kelvin values mean less lumen output from the bulb.

you are right tux, my bad. i was in a rush and trying to make a point and misspoke.

how do higher kelvin values mean less lumen output? the color temp is controlled by the gasses in the envelope, nothing more. how can i buy two 23W, 1600 lumen CFLs and get one in 6500K and one in 2700K?


-shake

[WhiteTux]

I don't really remember.. but i know that it does.. For example, look where a black light would be on the color spectrum, and it doesnt putt off much lumen at all. Cooler colors tend to produce less lumen.. (higher k values, are cooler colors, not assuming that you don't know, just mentioning it).

[Phant0m]

I believe it is the opposite, Lower K = less lumens. As lumens are based upon the human eye, we see less red light, making the lower scale of K (ie red/warm light) less intense.
"...our perception of red light compared to our perception of yellow light of the same radiological intensity makes the red light seem much less bright than the yellow even though they are equally intense."
The Perceptive Efficiency of the Human Eye as a Function of Wavelength (http://www.sjsu.edu/faculty/watkins/eye.htm)


Side tracked a bit though, yes both will be fine.

Goodluck,
phant0m

[jon420]

Using both will actually benifit you. Just try to stay further on the 6500k side while vegging and the 2700k while flowering. Staying closer to the 6500k for veg will keep stretching to a minimum but make sure you keep them very close, without touching the plant.

[captaincola28g]

both will be just fine, add more the bigger the plants get. Full grows with mixed spectrums is overlooked these days. but can be rewarding. just try it:D

[StoneMeadow]

The K is actually for Kelvin. It measures the temperature of the light emited from the bulb.. And, higher kelvin values mean less lumen output from the bulb.

You're partially correct. Color temperature (expressed in Kelvins) is just an engineering standard that compares the dominant spectrum of the bulb with that of an ideal black-body radiator. (You can read about it here (http://en.wikipedia.org/wiki/Color_temperature).) However, a cfl or florescent bulb's efficiency is not directly related to its color (k). What you're referring to here is the bulb's luminous efficacy (http://en.wikipedia.org/wiki/Luminous_efficacy), which is the ration of lumens of light output to watts of power consumed.

With ideal black-body radiators radiating at the same power, efficacy does drop off with color (k), but cfl's and florescent bulbs are not black-body radiators, and different types of bulbs are more or less efficient at different colors. It is safe to assume that the lumens declared on the box the bulb comes in closely correlates to the dominant color.

To the OP's question, I agree that mixing 2700k and 6500k bulbs will produce a good healthy grow. There is no reason NOT to mix them.