Off the shelf retail store screw-in LED and CFL bulb comparisons

Looking great, blynx! Happy Holidays!
Seems those leds do a great job in your cab!

Goats, I am running 9) 16w LEDs over a 2x3 area. You'll want to space the bulbs about 8-10 inches apart for nice, even coverage.

Ace Purple Haze Malawi x Napalm (which is destroyer x fire og kush) at 6.5 weeks:


Mango Carrot Zamaldelica x (Purple Thunk x White Widow) in veg. This one has been abused, beaten, chopped back, snapped, twisted all in an effort to contain the vigor of the Zamaldelica. It hasn't worked. Sooo, I tossed it under a 30"x18" screen. I'm going to give it 2-3 more weeks of veg till its ridiculous again and throw it into flower.

Here are all the buds from the last round in the 11" x 11" cab.

Gorilla Glue #4

Flowered under 30w of LED for 70 days

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Some bud closeups

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and the final dried weight

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Gotta say I'm happy with 33.46g from 30w of light.

I usually run 115w (5 x 23w) CFL in this cab.

I looked over the yields from previous rounds and the overall average is 32g per run.

I've hit the average yield for the 11" x 11" cab using about 1/3 of the wattage I usually run.

quite a thread blynx, damn, 1 gram+ per watt in micro
many don't like that measure, gpw, but you gotta take notice of this kind of result

blynx said:

Gotta say I'm happy with 33.46g from 30w of light.
I usually run 115w (5 x 23w) CFL in this cab.
I looked over the yields from previous rounds and the overall average is 32g per run.

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1 gram per watt is exactly what the big lighting manufacturers brag about.

Whats more impressive to me is that it takes 115w of CFL to do what 30w of home store LEDs can. It also means that 10w LEDs are (at least in this case) 3.6x as effective per watt as 23w CFLs.

PetFlora said:

When you read the data on these lights they only have ~ 80 lumens per watt

Real world for growing ounces should be > 150 lpw, many newest offerings have greater than 300

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yes it SHOULD, this topic obviously proved that...

wow - i was toying with the idea of using these sort of LED bulb's when i first seen them not to long ago. After seeing this thread my mind is definetly made up.

quick question - the only wattage i can find locally at the moment are 60w & are priced around 4.99 UK pound's each. brand is philip's. would you say this is a good price?

scrap that last post, i just re-read the info of the bulbs and they are 9w equvil - 60w.

Poundland has branded 6 watt warm white bulbs (SES). 10 SES base holders £10 pound on ebay. A 60 watt array for £20??? hmmm .

PetFlora said:

When you read the data on these lights they only have ~ 80 lumens per watt

Real world for growing ounces should be > 150 lpw, many newest offerings have greater than 300

Click to expand...

Lumens are a silly measurement to use when you are using lights to grow plants like we do.

We are concerned about the amount of light hitting our plants and this can be measured in lux.

Lumens are the total amount of light emitted from a bulb. They are calculated by putting a bulb inside a spehere and measuring the total output of the light.

Lumens were used so people could understand how a lower wattage CFL could produce the same light output that a higher wattage incandescent does.

They use a sphere to capture and measure the total light output of the bulb because incandescent and CFL bulbs emit light in all directions from the bulb.

Here's why I don't think using lumens are a good measurement, especially when looking at LEDs.

Let's say we have a CFL that emits light in all directions and it has a total output of 800 lumens.

If you put the bulb into the sphere to measure lumens and you take a lux reading 1ft below the bulb, you will get a reading of X.

If you could block the light from hitting the top half of the sphere, you now only have half the lumens (400), but if you take a measurement of the lux 1 ft below the bulb, you will still have a reading of X. The intensity of the light does not decrease because the lumens got cut in half.

This is because lumens is total light output and lux is a measure of light hitting surface at a specific point.

It also shows why you can't correlate lumens (silly measurement of total output so people can compare incandescent/cfl) with lux (actual measure of light hitting a surface, ie the canopy).

Let's say we have a screw-in LED bulb that has a total output of 800 lumens.

The construction of this bulb is such that a bunch of small individual LEDs are mounted on a board and pointed in one direction. They use the plastic lens to help evenly diffuse/spread the light so it's usable replacement for incandescent/CFL bulbs they are trying to replace.

If it takes this plastic lens to lower/diffuse the light so that the total output is 800 lumens, shouldn't the lumens increase when this lens is removed?

Lux measurements 1ft from the bulb are going to be different than an incandescent/CFL because the LEDs are directional.

Lumens are the same because its total output of the bulbs (800), but lux is different because it is a measurement of light hitting a surface and the LEDs direct their light differently than the more evenly spread incandescent/CFLs.

Since an LED is projecting light to only half the sphere, the light has to be brighter (ie higher lux reading) to the half receiving the light then the amount of light coming from a bulb with the same lumens that illuminates the whole sphere.

lumens are for humans!

Earlybird said:

Poundland has branded 6 watt warm white bulbs (SES). 10 SES base holders £10 pound on ebay. A 60 watt array for £20??? hmmm .

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6w though.. personally looking for a little higher wattage wise so i dont need as many bulb's?

Anything at or above 10w should work fine. I like 16w LEDs because they're stupid bright.

I would consider 8.5w LEDs (60w replacement) to be the minimum acceptable for growing. I used four 8.5w to replace four 23w CFLs which is slightly brighter, but hardly has the wow factor of my 16w units.

If you spaced 8.5w units close together, you could probably slam them down close to the canopy and get similar light readings as the higher wattage units, but I'd rather just buy the 10w, 12w, or 16w unit and call it a day.

PetFlora said:

When you read the data on these lights they only have ~ 80 lumens per watt

Real world for growing ounces should be > 150 lpw, many newest offerings have greater than 300

Click to expand...

Can you provide examples of leds that are greater than 300lpw? I haven't seen those yet

Terpene said:

Anything at or above 10w should work fine. I like 16w LEDs because they're stupid bright.

I would consider 8.5w LEDs (60w replacement) to be the minimum acceptable for growing. I used four 8.5w to replace four 23w CFLs which is slightly brighter, but hardly has the wow factor of my 16w units.

If you spaced 8.5w units close together, you could probably slam them down close to the canopy and get similar light readings as the higher wattage units, but I'd rather just buy the 10w, 12w, or 16w unit and call it a day.

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im currently building a cab which will house 4-6 10w or 12w LED'S as lighting, ill post some photos as i progress. - this thread inspired me to do the switch from cfl.

Here's the scrog cab a bit after nine weeks of flowering.

C99 x Shire (SSSDH)

Day 66 Flower

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She'll be coming down soon.

going for the 60w world record!

Here's the progression pics of this last round in the 11" x 11" cab.

Gorilla Glue #4

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