lumens question

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cyberquest

Junior GreenThumb
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ok new to this so i want to make sure i am calulating everything correct.

first lets describe there encloser. its just a small upstairs closet, 7'h x 3'w x 2' d and the whole inside is lined in reflective material.

lights:
2 GE CFL 20watts 2700k 1200 lumens


4 GE CFL 26watts 2700k 1650 lumens



1 GE Plant & Aquarium F20 20watts 750 lumens 24" (couldnt find the k rating, CRI is 90) (also couldnt find a pic of it)


so we have:
1650 x 4
1200 x 2
0750 x 1
____________
9750 total lumens


i only have one plant in the closet right now so does that mean that plant is getting all 9750 of the lumens?? since its not sharing that light with any other plants??

the lights are fixed in a light fixture i got from a freind that she used on her iguana that just died recently. it houses the 24" tube light, and has two regular style screw bulb outlets and all of them have their own on and off switch. i have the two screw type fixtures split into two bulbs so they hold four bulbs total now. one cfl is in the overhead light that was pre-exsiting in there and have another on a pod light set up.

they sit now roughly 7 inches away from the light.
 
cyberquest said:
ok new to this so i want to make sure i am calulating everything correct.

first lets describe there encloser. its just a small upstairs closet, 7'h x 3'w x 2' d and the whole inside is lined in reflective material.

so we have:
1650 x 4
1200 x 2
0750 x 1
____________
9750 total lumens


i only have one plant in the closet right now so does that mean that plant is getting all 9750 of the lumens?? since its not sharing that light with any other plants?

I see what you've done. Not quite right.

It's lumens per/square foot of area.

Your area is 2 x 3 feet = 6 square feet of area.

9750 divided by 6 = 1,625 lumens per/sq.ft.

That's roughly half of the minimum required.

You would be better off using two 150 watt hps. That would give you even lighting across your grow area and provide about 15,500 lumens each for a total of 31,000 lumens.

This would provide you with 5,167 lumens per/sq.ft. which is perfect.

Good luck man.
 
I thought you had too little!! See, in an area the size of what you're using, it costs a LOT in $ for CFL's to get the amount of lumens. If you're paying roughly $4 per 1000 lumens for CFL's, then you're looking at about $96 dollars in light bulbs alone to get to about 4000 lumens per square foot. In a 6 square foot area with an average 400w HPS, you're looking at 8333.33 lumens per square foot (at a certain distance form the light)
Basically, a 400w HPS would be perfect for your space. You can raise it up higher from the plants if you think you're giving them too much light, which I doubt will actually happen. I'm growing in a 4 square foot area with my HPS.

Also, plants don't 'take' lumens. You need 6000+ lumens per square foot no matter how many plants you have.
 
ok i see what your saying now!

i made my trip to the hardware store and found dusty on the shelves 2 shp 50watt bulbs, a 70 watt one, and a wide selection of mercury bulbs but i believe i read that those arent the correct type i need.

now SHP bulbs require a ballast to run them correct? what type of ballast is it? would a ballast from say a flouresent work to power it or maybe a one for a mercury light? reason i ask is i found at a local tractor supply store a nice large mercury light which i believe has the same sized socket for the bulb and it was only like $30 and the SHP bulbs i found were about $30 too, so for $60 if i could make say that 70 watt or maybe even just a 50 watt added to what i already have work then i could swing that $$ wise right now.

if not what i need to do is just find a smaller area maybe for my setup so i reduce the square footage i have. then come tax return time i will spring for a nice SHP fan cooled setup and go all out.
 
It's actually "HPS" standing for High Pressure Sodium. Yes, they need a ballast and fixture to run, are you only finding the bulbs?

Relocating to a smaller area is a great idea, make sure you have a fan and are monitoring the heat.
 
cyberquest, you need a HPS fixture and ballast. Just because it fits something doesn't mean it's safe to put in it.

Talk to someone who is an electrician if you're not going to buy them as a unit. Be safe man. If you try to save 25 bucks and burn your house down, it's not a good trade.
 
ok more shopping tonight payed off, at LOWES they have a small 70watt HPS security spot light. price was only $75 thats in my ball park so maybe next week i will pick one up and probably so with a 100watt bulb instead of the 70 since it will have fans blowing and keeping it cooler. i will see if i can find it on their web site and post a pic of it.

i also ran across some 150w CFL while i was there that put out 2600 lumenes instead of the 1650's i have now, sad thing is i dropped one of them taking it out of the package and broke it....lol. but it just raised me 2600 lumes, would have been 5200 if i wouldnt have dropped the one, got to see if i can find my receit and try and exchange it claiming it was broke when i took it out...lol.
 
cyberquest said:
ok more shopping tonight payed off, at LOWES they have a small 70watt HPS security spot light. price was only $75 thats in my ball park so maybe next week i will pick one up and probably so with a 100watt bulb instead of the 70 since it will have fans blowing and keeping it cooler. i will see if i can find it on their web site and post a pic of it.

i also ran across some 150w CFL while i was there that put out 2600 lumenes instead of the 1650's i have now, sad thing is i dropped one of them taking it out of the package and broke it....lol. but it just raised me 2600 lumes, would have been 5200 if i wouldnt have dropped the one, got to see if i can find my receit and try and exchange it claiming it was broke when i took it out...lol.

Seriously, if you're going to spend $75 on a 70 watt, why not get a 400 watt for twice that price, $150????
 
well i guess i dont have a good answer for that other then i dont have plants already going to have bud to smoke so i am still paying the "man" for the dirt he is growing, so me having $150 in my hand that doesnt go to him is rare...lol.

oh yeah did i mention i am un-employeed right now thats what started this whole project cause i have too much time on my hands. lol

so lets just say that $75 is easier for me to have in my hand then $150. i know i know just rough it and buy it, i am working on it trust me. this is all just fun right now till i actually produce something then we kick into full blown growing.
 
cyberquest said:
well i guess i dont have a good answer for that other then i dont have plants already going to have bud to smoke so i am still paying the "man" for the dirt he is growing, so me having $150 in my hand that doesnt go to him is rare...lol.

oh yeah did i mention i am un-employeed right now thats what started this whole project cause i have too much time on my hands. lol

so lets just say that $75 is easier for me to have in my hand then $150. i know i know just rough it and buy it, i am working on it trust me. this is all just fun right now till i actually produce something then we kick into full blown growing.

I hear what you are saying, but unless you think that this will be the only time you ever grow, I would wait and save for the HPS. The 70 watt light just isn't worth it, IMO
 
i guess i am just looking at it like i already have around 2500 lumens or so in there now, so i just thought that the 70 watt added to what i already had should be enough for them.

i have a back asswards way of doing everything in life not just growing....lol.
 
ok on the lowes website i found a 150watt one for $88, its in a fully enclosed case. so i could up the 150 to a 200 maybe even a 250 added to what i already have would put me roughly at 5325 lumens which is within the required amount.
 
cyberquest said:
ok on the lowes website i found a 150watt one for $88, its in a fully enclosed case. so i could up the 150 to a 200 maybe even a 250 added to what i already have would put me roughly at 5325 lumens which is within the required amount.

I understand the back asswards thing, it's happened to me a few times too. Trying to find s substitution will always leave you with a substitute that is not as good as what you will need in the end. Go check out the grow journals and note what lights are being used.....
 
yeah i know its just trying to cut a corner here and there and in the end you spent more then you would have just dropping the cash from the start.

i have so many car projects going on that the growing is playing second fiddle to the cars. after xmas i have one in the garage that i have been using for parts that will get scrapped and then we will have more room for a more extensive setup. this is just a "lets see if it will grow" thing right now till it gets moved up the priority list a little....lol
 
Yeah, definately... you will want and need bigger as u get a lil experience under your belt...
 
my dad told me the other night he was getting me another digital camera since mine took a crap and hes tired of me borrowing his all the time for my car forums.
i am a moderator atanother site and i do "how to manuals" for the conquest so i post around 150 pics a week there for the manuals.

i need to get some shots of my setup after xmas so you have a better idea of what i am working with. trust me when i say once i get a working digital in my hands again there will be plenty of pics!
 
I wouldn't post personal informatin about yourself here. IMO
 
well yeah thats a given, trust me when i say that my whole setup is a armsnatch away from a flush down the toliet if there is a unknown knock at my door.....lol.
 
70watt HPS security spot light. price was only $75 thats in my ball park so maybe next week i will pick one up and probably so with a 100watt bulb instead of the 70
..70 w ballast/100 w bulb?
...the ballast "has" to match the bulb....
 
I hear a lot of excuses. Just man up to the facts and make a move one way or another! Why do things half-assed?
 

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