Color Temperature (Kelvins) & Lumens ???

Hi, I keep reading that the right CL is 6500k for Vegging...
My question is:
Is it better to have Higher CL like 7000k etc etc then 6500k and which is more
important a 6500k bulb with 1100 lumens or a 5000k bulb with 1800 lumens as a
example???

Thanks

http://futuregarden.com/lighting/PAR_chart.jpg I hope this will help you out. You wanna use around 5700 k during veg and 2100 k when flowering

u have color which dictates what "range" of color the bulb is outputting, then u have lumens which relates to the actual output of light, so both r equally important. To answer ur question directly, I would rather have the 5000k bulb with 1800 lumen output vs the 6500k with only an 1100 lumen output. Ideally veg range is 6500k, BUT some people use the HPS bulb ideal for flowering with 2700k or even 2100k for the entire grow so that tells u that the lumen output is the most important factor.

So Its Lumens, I appreciate that, Thanks .
Also Thanks for the chart

On the Chart it say 5000k is about useless, while 5500k is the best, is this accurate?
Also If I had a 5000k bulb that put out 1800 lumens, it would be worst the a 5500k/6400k bulb that put out 1000 lumens?
Is this Correct?

no that is not how it is read. where the wording, like daylight metal halide 5500k starts, everything from that point & on is within that range. Also note, this chart is not using one bulb rather several for comparison. The 5000 in this chart is not using a MH bulb to tell u about the 5000 range, rather a fluorescent, & then down at the other end, the 2700k is a standard incandescent, & so forth u see. So in that sense it is not very useful as u would never use a standard incandescent, which gives out next to no lumens as relative to growing & actual bulbs for growing.

Thanks, So a 5000k bulb with 1800 lumens, would be a lot better then a 6400k with 1100 lumems , and Im talking about using a CFL which Im about o buy some???

bump ..........................................................

this is kinda hard to explain, lets start with Bulb color Temp.

When a bulb says 5000K or 6500k that is simply referring to its peak color temp. many/most bulbs emit light at many different temps all at the same time, some have numerous peaks slightly lower than the rated one at other color temps. generally the highest peak represents how we see the light given off by it. to get an accurate idea of the % color temps of a bulb you need to see the spectrum graph for the bulb.

now lets talk lumins, this is the amount of light put off by the bulb. now take 2 graphs of bulb color temps, lets say a 1000watt MH 5500k bulb and a 23 watt 6500k CFL. the 1000w MH produces about 130,000 lumins and the 23 watt CFL about 1800. So the HM produces nearly 75 time the light the CFL does.

now remember those graphs we looked up of color temps of different bulbs and how they show the light ranges in percent output. when shown as % output the 6500K CFL appears to line up very well with the light that can be absorbed by a plant for photosynthesis and the 5500k HM seems to line up ok but not as well as the CFL. now heres the kicker, to see how well each one preforms in reality, imagine laying all 3 graphs on top of each other and seeing how much of the absorption graph each of the light spectrum graphs cover up. Still looks like the CFL is coming out on top right (woot cheap light out preform the expensive ones!!!, except there is one more thing) now take the CFL light output graph and divide its output at all temps by 75, now there is only a tiny little line at the bottom of the graph that represents the actual usable light produced by the 23 watt CFL (using the 1000watt MH as the standard).

i hope by explanation makes since with out pics. also 1100 and 1800 lumins is pretty insignificant in reality and would produce a nearly unnoticeable difference IMO, but if your talking 1100 and 130000 thats a different story. also penetrating (the amount the light degrades over a distance) is important to factor in if you are veging larger plants.

Thanks I appreciate that and I understand that MH and HPS light are by far better, but just going by CFL is it more important for the amount of Lumens or
from 1. 5000k with higher lumens or using lesser lumens using a 6400k CFL???
Btw I have read on here that a couple people have said If u put 2 - 2000 lumen lights together u still would oonly be getting 2000 lumens instead of 4000 lumens ???
If this is true, why would that make up to 8 bulb light fixtures?
Thanks again

Anyone? .........................................................

ok if your talking cfls, 6500k are pretty much the best you can get, the bigger the better. as far as the addition of multiple lights at the same lumins, well well i wont say putting 75 of them on one plant will = a 1000watt MH but i guarantee 2 is better than 1 and 3 is better than 2 but im not really certain if you actually have 3600 lumins with 2 and 5400 lumins with 3 or if you only end up getting about 5000 lumins with 3 but in the end your plants will grow better with 3 than they did with 2.

Thanks, So If I get u right then, the 6400k bulb is more important then a5000k bulb with more lumens then the 6400k ?

rak1 said:

Thanks, So If I get u right then, the 6400k bulb is more important then a 5000k bulb with more lumens then the 6400k ?

Click to expand...

i have no idea what you are asking man, if i knew a way to say it more clearly i would but your asking the same question over and over and we are telling you the answer over and over in the best way we can. if your looking for clear cut directions to growing then this place is full of guilds. most of use are on here discussing new or better ways to do things. therefore we provide ideas and reasons for other to build on and draw there own conclusions. some ppl don't like to be told "do it like this because its the only way it will work". but would rather be provided the info and suggestions and then they try there way and share the results in hopes of furthering the cause and making improvements.

that being said.

go buy 2 23 watt 6500k CLFs per plant that you wish to grow and put then 6 inches away from the plant as a seedling. after 1 week move them to 4 inches away, at week 3 add 1 more 23 watt cfl per plant at 4 inches. after 4 weeks your ready flower. go buy 1 68 watt 2700k cfl and 3 23 watt 2700k clfs per plant and put them at 8 inches at 12/12 and leave them that way for 2 months. pick your weed and dry it in a dark room at 65 degrees for 1 week. clip the nugs and put in a jar for 2 weeks, open the jar once a day during those weeks.....done

there is the quick, cheap, and dirty. i hope it answers all your questions in a very direct fashion.

as far as the importance of each aspect of the growing, there is no way to give you definite answers or "facts", if you will.

Is 6500k better than 5000k at the same power? YES, if you want short bushy plants

Is 2000 lumens better than 1000 lumens? YES, if you want fast growth

Is 5000k at 1800 lumens better then 6500k at 1500 lumens? IDK, but i would go with the 6500k and get more of them.

Maybe Im just not understanding how you are putting it, let me clarify a little:

Which is better for vegging plants?

A. one 6400k bulb with 1100 lumen output or
B. one 5000k bulb with 1800 lumen output ?

I think u have answered somewhat, but I just wanted it to be clear.

Justin00 said:

as far as the importance of each aspect of the growing, there is no way to give you definite answers or "facts", if you will.

Is 6500k better than 5000k at the same power? YES, if you want short bushy plants

Is 2000 lumens better than 1000 lumens? YES, if you want fast growth

Is 5000k at 1800 lumens better then 6500k at 1500 lumens? IDK, but i would go with the 6500k and get more of them.

Click to expand...

Ok thats cool, your not sure.
Thanks for replying about it.

rak1 said:

Maybe Im just not understanding how you are put it, let me clarify a little:

Which is better for vegging plants?

A. one 6400k bulb with 1100 lumen output or
B. one 5000k bulb with 1800 lumen output ?

I think u have answered somewhat, but I just wanted it to be clear.

Click to expand...

i posted while you were replying:

as far as the importance of each aspect of the growing, there is no way to give you definite answers or "facts", if you will.

Is 6500k better than 5000k at the same power? YES, if you want short bushy plants

Is 2000 lumens better than 1000 lumens? YES, if you want fast growth

Is 5000k at 1800 lumens better then 6500k at 1500 lumens? IDK, but i would go with the 6500k and get more of them.


as for your exact question i would get 2 6400k bulbs, or a bigger one and be done with it =)

one last thing to always remember...we are growing weed not doing brain surgery. bending the rules a little here and there is not gonna kill you or your plants =), last year when i was first starting i felt the exact same way, i wanted the best and to know exactly what the best possible thing was. then after a few crops i realized its all grey area, there is no white and black what will and wont work (well yeah i guess there is at the extremes, but you got a lot of room to play with). go with it and get a feel for it, change a few things and read what some other ppl do and change a bit and see how it works. Happy growing =)

All available to me atm is those two choices, but I get what your saying and thanks