Full spectrum low lumens, or non-full spectrum high lumens??

[fr0stysm0ke]

Hi All,

I am a bit confused. I have been reading around that full spectrum lights and lot's of lumens are good things for the plants. However what if I have one bulb that I am not sure is full spectrum and it has been rated with 740 Lumens. Then I have another bulb which is full spectrum, a bit less kelvins and the approx initial lumens is 600. Which bulb is better in this case?

Thx in advanced!

 

[Papa]

'a little more information please.

what lamps do you have?



Papa

 

[convex]

Hi All,

I am a bit confused. I have been reading around that full spectrum lights and lot's of lumens are good things for the plants. However what if I have one bulb that I am not sure is full spectrum and it has been rated with 740 Lumens. Then I have another bulb which is full spectrum, a bit less kelvins and the approx initial lumens is 600. Which bulb is better in this case?

Thx in advanced!

The typical luminous output of CFL's is roughly 60 to 70 lumens per watt, depending on manufacturer.

Your stated you have a 740 Lumens bulb ... either a very efficient 9 watt or inefficient 13 watt bulb.

Don't let mommy catch you growing in your old 'puter case.

 

[fr0stysm0ke]

Hah yeah. My mommy would have to drive about 2,000 miles first, and cross international borders ;D I moved away from home over 25 years ago.. ;D

My box is a bit over 6 feet high, so far from micro but I am trying to keep it small.

The 740 lumens was info I found online about a bulb I have.

Brand Name on the bulb: Globe 18" 15w - 120v - F15T8DL - 6,500kelvin - Supposedly 740lumen

I figured this was false. So I have replaced it with a Sylvania Full Spectrum Daylight - 6,500k. The box says Approx initial Lumens: 600.

and a: Tensor Vision Max 27w, 6,400 k : again according to Internet sources: Lumens: 1550

Thx in advanced!

 

[Seamaiden]

You're using T8 fluoros, you can usually assume the manufacturer specifications are fairly close, unless you have a meter that says otherwise I think you can safely assume the numbers are good.

What are you using these for, vegging? If so, you can range the Kelvin (color temperature) from 5,000K-6,500K and easily be within what's considered the "daylight" range, it's what's closest to the actual color temperature of the sun.

Lumens can be a misleading number, it's what the human eye perceives, which is quite different from what plants use to make sugars (grow). They're a start, though. It sounds like you're using short bulbs, so if it were *me*, I'd pack 'em in there, including on the sides if possible. I would also mix spectrums, mix warm whites (2,700K-4,000K) with those daylights, 50/50. Keep them close to the plants, expect the plants to wrap themselves around the bulbs, you'll have to control that.

 

[fr0stysm0ke]

Hi Seamaiden,

First thx for the reply.

I am using T8 fluros for veg correct. I have bought another 18" T8 Sylvania - Full Spectrum 6500k, Initial Lumens says 600. As far as Kv goes, I should be outputting around 1200kv. I am trying to figure out how to know when I need more lights. It's very very bright on the inside, not good on my eyes to be in there for more than a few minutes.

Judging by my kelvins, I think I am close. Judging by my lumens I think i am way off?
A bit over 1000lumens roughly

 

[convex]

What are the dimensions of your chamber?
What are your goals within chamber?
Are you planning on flowering with 15 watt T8's?

 

[fr0stysm0ke]

Chamber Specs
Height: 68 Inches
Width: 30 Inches
Depth: 18 Inches

It's like an old tool cabinet move-able shelves etc, currently i have them a bit over 2 feet apart. The plants are all within 1" of light on all sides. I was going to flower with HPS or some sort of MV, still un sure of size too use etc. I can change the height easily to any distance within 68inches tall. The width and depth I am stuck with.

Goals: 1 or 2 plants. Mainly just checking things out learning, for future possible bigger ones. Now If I can keep it growing cool, if I can get a bit of smoke out of it, even better. My first time so my expectations are not very high ;D I am wide open to suggestions improving what I have within the size constraints above. My first time I don't want to go all out and spends a load of money on it. Until I have a better understanding of what I am doing first of course.

Thx for reply.

 

[jyip]

i'm pulling up a chair to this one!

what kinda strains ya gonna have going in there ?

 

[jyip]

btw, i have only flowered in hps, and only vegged w/it as well, dispite knowing that MH would work better in veg than HPS will
i'm curious to see what the cfl's can do

 

[big twinn]

First, will this light be used for Veg, Flower, or both??

Full spectrum is certainly ok, but i'd recommend getting bulbs spec. for veg and flower that way you can just switch them over.

For veg, use Lower wave length spectrums (around 400nm) which is closer to the ultraviolet spectrum (lights look blue to the naked eye). this encourages tighter internode spacing and more branching.

for flower, use higher wave length spectrums in the red wave length. this encourages flowering and will produce bigger nicer buds.

the more lumens, the better. I wouldnt focus on white light particularly, unless you plan to use it for additional spectrums...there are much better spectrums for your needs