Lumens, Lux, and Adding It all Up

Great thread, I know the HPS/MH people laugh at clf's And if you are tyring to grow some tight bud with 6/45w cfls they are probally right most of the time. I have been looking at both. The high heat issue(I know cool tube) brings me back to cfls. I can get 14 200w 9250 lums cfls 7 6400k and 7 2700k for 406$. I think this is comparable to a 1000 w MH/MPS 421$ or at least close. I would like to hear some thoughts before I go one way or another

Yuma said:

Great thread, I know the HPS/MH people laugh at clf's And if you are tyring to grow some tight bud with 6/45w cfls they are probally right most of the time. I have been looking at both. The high heat issue(I know cool tube) brings me back to cfls. I can get 14 200w 9250 lums cfls 7 6400k and 7 2700k for 406$. I think this is comparable to a 1000 w MH/MPS 421$ or at least close. I would like to hear some thoughts before I go one way or another

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2800 watts of power usage compared to 1000 watts. almost tripple the power usage, and still less light. cfl's DO put off heat too, it's just more spread out over multiple bulbs, not just a single concentrated bulb. you could end up with more total heat in the room then you would with a single 1000 watt bulb. having so many bulbs also makes it harder to contain that heat. on the other hand, cfl's can spread out the light more evenly over top the whole grow and can be much closer to the tops of the plants. I think you'd be happy with a 1000 watt hps.

Here is a chart, not sure how accurate it is. Does this seem bias towards the HID's or is it atleast close?

sportsballer06 said:

A confusing misconception often perceived amongst many cultivators is the idea that more lumens equals more yield. Think of lumens as a measurement of the amount of light observed by the naked eye, and not used by the plant. Depending on the situation, brighter light with an obscure spectrum may not prove as proficient as weaker light with a balanced plant specific growth spectrum.

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Could mixing CFL's (165w red spectrum and 60w blue spectrum) + a 600W HPS be, possible, bad in flowering? Could it lead to a less "balanced" spectrum that isn't particulary good for flowering and it would work better with just the 600w HPS?

Thanks.

it would work better with just the hps light all those other light would just be a waste of space

i am using 4 23w CFL's daylight spectrum from ACE hardware down here in Costa Rica for my mother's they seem to be loving them and would like your thoughts on flowering with CFL's mixed in with HPS ?

what did you hear back down in costa rica and wondering if i shouldnt try flowering under a bunch of cfl's cause little to no heat and can move lights as necessary

lilb2662 said:

it would work better with just the hps light all those other light would just be a waste of space

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space is no problem if that's the only reason not to use CFL's mixed with a HPS. I'm just wondering if it could lead to a spectrum that is less good for flowering and if it could cause smaller buds becaue of that.

I am using a 400 watt hps with cfl's on the edge of the space. some of the leaves still do angle towards the cfl's. they aren't useless space takers. the hps is only emitting light from a single central bulb, then reflected out around the plants as best as you can. cfl's on the sides can offer the plants much more light where they need it most, on the edges where the hps has trouble reaching.

there's more to it then just saying more lumens = better. a lot of people grow in places where there is no light reflecting back from the walls, like in a shed. a lot of grows don't have a wall or door right in the front. cfl's can help a lot to make the conditions for the plants more perfect for them to thrive.

well in that case the lights might come in handy but its cheaper to get mylar all the way around it and you will end up with the same results in stead of bying cfl light and putting them around the edges

sportsballer06 said:

A confusing misconception often perceived amongst many cultivators is the idea that more lumens equals more yield. Think of lumens as a measurement of the amount of light observed by the naked eye, and not used by the plant. Depending on the situation, brighter light with an obscure spectrum may not prove as proficient as weaker light with a balanced plant specific growth spectrum.

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Excellent point. You do realize, don't you, that you just stated the primary advantage LED technology is homing in on: spectral emission solely in bands of Photosynthetically Useful Radiation.

Great thread!

Hey i m growing in a very little space for now 2x2.5x2 but it has exccelent air movment. i am using 2 200watt equivelant and 2 100 watt equivelant cfls. they just spouted a few days ago. is this enough light for now?

thanks

ceestyle said:

we'll see how it's received. i'm getting a lot of "CFLs suck, so we don't care", but it's applicable to HID too...

man, i should take a picture of the burn on my arm i just got moving my light meter under that HPS. *sizzle*

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CFLS do suck... Didnt you know hps bulbs get hot lol no offense

WHat is more important for growing more lumens, more watts? Seems to me the heat is the issue and LEDs will solve some of the heat issues. Even though they are expensive. Any case studies on LEDs?

ceestyle said:

It will. What will be especially interesting is to compare the light distribution.

By the numbers, each should provide about the same lumen count.

6 x 42W = 6 x 2700 lumens ~ 16200 lumens

1 x 150W HPS ~ 16000 lumens

There will be errors due to my cheapass HPS and the different spectra, age, etc., but we should be able to get the point.

What is especially interesting is that at the corners we should see better coverage from the CFLs, as they're closer, while at the center, the HPS should be better. And of course all of this will change with the distance from the canopy.

Let experimentation begin! (but after dark, 'cause it's hot as shit in this room atm)

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Im working on eventually earning an advanced degree in physics, currently about to become a senior undergrad at a top physics school....anyway it is awesome to see in action, GREAT POST


thought I'd only see pi * r^2 in emails to professors

Hey Everyone, great post.

According to the Jorge book flowering plants should receive 10,000 foot candles. But all of the light meters I've seen, including the one's sold at hydro shops for HID lights, only measure up to 5,000 foot candles.

Obviously, there's an inconsistancy somewhere. Can anyone recommend a good quality digital light meter? I would even prefer paying a little more for a quality instrument, $200-250

Also, does this sound right, 10,000 foot candles for flowering plants? It seems that all light meters measure in foot candles, so does anyone know how man foot candles plants need?

Jolly interesting.

So how many lumens is my 400watt groloux outputting?

Iam interested cos my posh LED has about 400, and that is ruddy bright. But my grolux is like looking at the sun!

toodle--oo

Jolly interesting.

So how many lumens is my 400watt groloux outputting?

Iam interested cos my posh LED flashlight has about 400, and that is ruddy bright. But my grolux is like looking at the sun!

toodle--oo

incidentaly, and not relevantly at all. Iam watching the news at the moment about the pope visitting Israel and palastine
I have never noticed before, but crikey, he is the spitting image of Emperor Sidious!

So, I noticed that I never see this on these grow forums but I have a question.

If plants tend to like the bluer spectrum (400-500nm) why not use Marine Aquarium T5's which are specifically designed for 420-460nm for the vegging phase and add some 50k's in as you get closer to Flowering?

Just a thought.