Envirolights better then HPS/MH? You decide!, Read this! - Page 11

mist420 · 08-15-2002, 12:53 PM

Hiya RG, thanks for all the comments and the scinetific data. I have reread all your posts and I have come to my own conclusion:my light is better then your light na na na!!!

Seriosly, great research and data, I will leave it up to 86 to figure it out as you really do make my head hurt will that info, hehe. But please do keep it coming. I do feel that the EVL has a great penatration rate and better reflexability no matter what any light meter or calcumacations say.

Also,

Quote:

Dank seedless commercial = $320 oz
Envirolite = $100
Grow supplies = $40
Money saved = $180
Smokin the bud you grew yourself = Well, thats freakin priceless

That was one of the best I have heard! Only one thing though, 86 got 5.5 oz off his last plant. Money saved should be $1540, not bad, not bad at all.

mist

08-15-2002, 02:19 PM

wassup regularguy

yep, it looks like you could actually do that. but you can't.

as you get closer and closer to the lamp, the denominator gets smaller and smaller, and the ft-candles WILL get bigger and bigger. but, what you're really doing there is concentrating the light onto a smaller and smaller area. the numbers go up because the area gets so small (same principle as a magnifying glass). so the illumated area at 1 inch distance is only 12.6 square inches - less than a tenth of a square foot!

and that's assuming you can somehow get all the light from the bulb!

so, how many envirolites would it take to illuminate my 5 ft. by 5 ft. grow area (assuming perfect efficiency) to about the same brightness as outdoors (10k lu/ft. sq.)?

i'm thinking i'll stick with the hps

regularguy · 08-15-2002, 02:42 PM

Jose
I think im going to stay HID too.

But, for those that have these requirements

1.cant keep the heat down
2.can keep the plants in a sea of green
3.have the money for that many EVL and can keep them less than 2 inches from the plant

You can grow weed that will get you high.

I still think it is a compromised solution and am on a quest for the best HID growing bulbs i can find. Also if i was to do a grow wit the flouros i would use tube flouros and keep the plants tied down or do a sea of green. You can buy enough different types of 4ft flouros to get the full spectrum and you would probably get decent bud.

KindBudde · 08-15-2002, 02:49 PM

Hey Mist, I just read your whole thread and it is brilliant how you figured all that out! Congradulations!

I got one ? I would like to ask you since you seem highly educated in the lighting dept.
ok..I have 4 seedlings in a pot with a cherry tomato clone and 1 flourescent light - it says it gives off 2700 lumens. Now I don't exspect to grow 4 plants with just this light. I am only gonna let them grow their first set of real leaves and then move them to another location. I am just doing this as a Flouro exsperiment so I can see if I can grow good healthy plants with just flourescent lighting. Let me know what you think! Thanks!

Peace & Love - Eric

08-15-2002, 03:18 PM

hey regular guy

looks like we're on parallel paths here

i just went through upgrading my lights, too. and spent hours and hours reading the boards and researching the net. after all that, i finally settled on the eye hortilux lamps. seems like one of the better hps lamps out there, getting ready to try it real soon now

let me know what you decide on, too

Agent86 · 08-15-2002, 10:17 PM

Hi Grow Bros:

Well I went ahead & bought a light meter. It gives readings in foot candles not lumens so I did the conversion to lumens for the figures below. 1 foot candle = 12.6 lumen.

Here we go, I did measurements with1 light on & then both lights on & here are the results.
All measurements were taken below the center of the bulb.
I guess I screwed the conversion up so I came back & edited it.
Thanks to Powercow9 These #s are now correct.
1' = 3,780 lumen
10" = 8,820
8" =11,340
6" = 15,120
4" = 22,680
2" = 37,800
1" = 56,700
at the bulb off the scale.

With 2 lights on.
These measurements were taken directly between the bulbs. I'm sure the reason the lumens start going down in comparison to 1 bulb is that the closer I got the lights were to the side of the meter & the meter was pointing at the center of the reflector not one of the bulbs.
Here are the results.
1' = 11,025 lumens
10" = 15,750
8" = 18,900
6" = 22,680
4" = 31,500
2" = 37,080
1" = 41,580

Here are some measurments I took at the lighting store of some other lights for comparison.
These probably are not very accurate as there were other lights on in the store. Nothing real close but I'm sure anough to skew the readings slightly.

400 watt HPS at 1' = 28,350
600 watt at 2' = 63,000 anything closer than 2' caused the needle to go off the scale.
1000 watt at 2' = 65,520 not much more than a 600 watt.
40 watt floro tube at 1' = 2,268
40 watt floro tube at 1" = 4,662

Hope this helps to figure things out.
I'll be watching to see what you brainiacs come up with.
BTW, Here is a pic of the light meter I used. It has a photovoltaic cell that reads the light intensity.

Later Grow Bros.
86.

Agent86 · 08-15-2002, 10:23 PM

(*&^^%%*&%^ Forgot the pic of the light meter> Sorry, here it is.

powercow9 · 08-16-2002, 12:49 AM

Quote:

Originally posted by Agent86
It gives readings in foot candles not lumens so I did the conversion to lumens for the figures below. 1 foot candle = 10.7 lumen.

Where did you get you conversion numbers from.. becuase in my book it's 1 foot candle = 12.6 lumens.. it comes from the area of a sphere with a radius of 1 foot.

so you would have to increase all your numbers by 1.2. Doesnt sound like much but here are a couple of adjustments.

1 light 1 foot
you said
3210 i say 3852
2 lights 1 foot
you said
9360 i say 11232
last 400 watt hps
you said
24075 i say 28890 ( a little closer to the bulbs rating of 36000)

But I digress.. first "why people think foot candles and lumens are the same". A foot candle is the light measured 1 foot away from a candle. A lumen is that same light over a square foot. If you measured when a foot candle/ lumen meter 1 foot away both would read the same.. but a foot candle encompasses the entire sphere around a candle to which there are 12.6 square feet or 12.6 lumens all around the candle.

ok but why argue about lumens in the first place..lumens where made up for photography.. it based on the human eye which my plants have none. For example a halogen has alot of lumens but cant grow a plant for S***. Lumens are only helpfull when comparing the same type of bulb like a 400 watt hps vs 1000 watt hps. What we need to be arguing is PAR or Photosynthetically Active Radiation or lumens for plant eyes... Par takes into account cri and kelvin temp etc. Accually there is a variation on PAR that I think is even better but I'l leave it here.

Some par watts of common lights

PAR watts of midday in the troppics.. is 2000 PAR

400 MH (110 PAR)
400 HPS (140 PAR)

1000 HM (470 PAR)
1000 hps (600 PAR)

update of interest.

lumens include green light.. which the plants dont use at all. Whats nice about this.. need to light your grow room at night.. you can safely do it with green lights without affecting flowering.

denspot · 08-16-2002, 01:28 AM

Agent 86 -

you said:
600 watt at 2' = 53,500 anything closer than 2' caused the needle to go off the scale.
1000 watt at 2' = 26,450 not much more than a 600 watt.

huh??? is the 1000w reading really 1/2 that of the 600w? and if so, how is it not much more???

Agent86 · 08-16-2002, 02:44 AM

Hi Guys:

First of all Denspot, I screwed up it was supposed to be 56,450. I'll go back & edit it.

Thanks for paying attention.

Now for the hard ?.
Powercow9, I got my conversion table from this site. I typed in foot candles in the search & found a thread giving 10.7 as the conversion. If that was wrong,

I didn't know. I'll go back and edit the results right now & do all the conversions using 12.6 as the multiplier.
Thanks for setting me straight on that one Powercow9.

In the owners manual for the light meter it says [quote]This meter is capable of reading illuminance, luminance, reflectance, & transmittance up to 5,000 foot candles(lumens per square foot). Here is the definition Stoney gave in another thread to describe a lumen [quote]LUMEN - A measurement of light output; relative to human perception
which refers to the amount of light emitted by one candle that falls on one square foot of surface located at a distance of one foot from the candle.

This meter is specifically designed for the measurement of radiant light energy that directly affects plant growth. This meter is not color corrected.

Here is another interesting thing I just read.
Most plants need at minimun 1000 ft. cl. of light intensity & a minimum of 15,000 ft.cl.hrs. of light per day to grow. meaning if the plants get 1000 ft. cl. of intensity an hour x 15 hours the will live.
And that 5,000 ft.cl. per hour is the most light intensity most plants can use, beyond that it will burn most plants.

And last for now but not least. We talk about lumens because thats the measurements the manufacturers give us to compare the different lights. If they listed par then we could go by that. But they don't list par, they list LUMENS so thats What we'll have to compare by.
Sorry Powercow9, if that seemed rude I didn't mean it to.

Well, now my brain really hurts I'm going to smoke a bowl & be right back.

Later.
86.

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