Watts/lumens per square foot ?

Resinable · May 6, 2012

By pythagorean scrog I just meant screens built like stadiums: on the low side they were about 30 something inches and about 66 inches on the high side giving a diagonal or sloped screen about 5 feet long. The room was 8ft by 12.5 ft with a very narrow walk way down the center; so I had two 5ft by 12.5 screens giving me 120 sq ft total of screen with bare bulbs down the center and vented hoods on either side. I had a lot more surface area this way than if I had kept the screens flat and was able to utilize the efficiency of bare vertical bulbs. It worked very well.

El Cerebro · May 6, 2012

Resinable said:
By pythagorean scrog I just meant screens built like stadiums: on the low side they were about 30 something inches and about 66 inches on the high side giving a diagonal or sloped screen about 5 feet long. The room was 8ft by 12.5 ft with a very narrow walk way down the center; so I had two 5ft by 12.5 screens giving me 120 sq ft total of screen with bare bulbs down the center and vented hoods on either side. I had a lot more surface area this way than if I had kept the screens flat and was able to utilize the efficiency of bare vertical bulbs. It worked very well.

That's what I figured, have done something very similar myself with bare verts. If we think in 3d a little, higher yield/space potential than simple flat for sure. What materials did you use for the screens?

Resinable · May 6, 2012

That's what I figured, have done something very similar myself with bare verts. If we think in 3d a little, higher yield/space potential than simple flat for sure. What materials did you use for the screens?

I screwed 1 by .75 inch strips to the walls and attached hooks to those; the bottom half of the screen was 2 by 4 for rigidity with metal hooks every eight inches; then I took home depot type nylon trellis and attached it so that it was very taut; when I harvest I cut the screen down. I had to do a great deal of training and pruning to achieve those yields and contort my body in uncomfortable positions for hours on end; however I don't know of another method that can achieve that kind of yield per sq. foot. Per watt is another story maybe if you have lots of space to work with.

If you have every studied any biology or chemistry you will probably remember the theme of surface area in nature is repeated again and again.

Lately I have copied Trichome fans method with chain and tightening device for building the screen frames; works great is fast and easy to build and take down.

El Cerebro · May 6, 2012

Resinable said:
I screwed 1 by .75 inch strips to the walls and attached hooks to those; the bottom half of the screen was 2 by 4 for rigidity with metal hooks every eight inches; then I took home depot type nylon trellis and attached it so that it was very taut; when I harvest I cut the screen down. I had to do a great deal of training and pruning to achieve those yields and contort my body in uncomfortable positions for hours on end; however I don't know of another method that can achieve that kind of yield per sq. foot. Per watt is another story maybe if you have lots of space to work with.

If you have every studied any biology or chemistry you will probably remember the theme of surface area in nature is repeated again and again.

Lately I have copied Trichome fans method with chain and tightening device for building the screen frames; works great is fast and easy to build and take down.

Very cool, thanks for sharing. I know that feeling, makes me want several extra hands for training, and certainly gets in the yoga workouts while gardening. Right on about space efficiency, sounds like you had it dialed. Will check Trichfans threads for that frame design.

Funny most people seem to think very two-dimensionally when it comes to vert-scrogging, yet surface area is more if done on a diagonal, and even larger if you take the concept further using all contours of the light's footprint. Bare vert bulbs also lend themselves to this shape canopy if hung a little higher than krusty-style.

hogan400 · May 6, 2012

Hey dankW, take a look at my first thread in the Uc forums and you can see the layout in my photos. Says 12k but I ended up w 10k. Ec for Uc was .5-.86 at the most, co2 1200-1400.
canopy varies w strain and I split this round to include coco so its taller. but typically I scrog about 2 ft of buds. Sometimes double scrog, but the plants may be 3.5-5.5ft tall. Imo the reflector type was moderate in importance. Example is all this german pebble insert and glass lense protection from Uv is of no value. Plants need Uv and if bulbs are replaced every other crop the diminished return was non measurable. I use 10"yield masters and some cheap batwings in between for spread. You should get 20-25 if you are a excellent grower.

Resinable · May 6, 2012

Curious about the UV comment above: I thought regular HPS and Metal Halides don't emit UV. Only Ceramic Metal Halides do and they are not very common. Please correct me if I am mistaken about this but this is my recollection.

dankworth · May 6, 2012

My unshielded digilux 1k MH in a super sun 2 gives me a tan pretty fast.
And a horti blue mh in 1k hung vert gave me a sunburn faster than that.
I have read the same thing, but I have my doubts.
I liked the story where dude had a mini-vscrog around his 400w cmh.
Went fucking with the canopy with the light on repeatedly.
Unfortunately for him his skin turned black on part of his hand due to uv.
Uvc?

hogan400 · May 6, 2012

You can find the info for most bulbs and the spectrum if you do a search. They all emit some Uv. Companies coat bulbs and lenses to reduce this but best I think is about 90%. Uvb.

ttystikk · May 7, 2012

hogan400 said:
You can find the info for most bulbs and the spectrum if you do a search. They all emit some Uv. Companies coat bulbs and lenses to reduce this but best I think is about 90%. Uvb.

ALL HID bulbs emit UV, the amount and type vary between bulbs but if you read the warning labels, they're very clear; do NOT attempt to look at or work around a bulb if its outer glass jacket is broken or you will receive UV radiation burns! I know for sure the old mercury vapor bulbs were the worst in this regard, it stands to reason that the next highest UV emitter is MH and HPS emitting the least. Least is NOT zero, so wear protection.

Gavita, well known for making reflectors without glass because of the efficiency advantages, has a glass cover on its 300w LEP plasma reflector for the same reason. LED manufacturers also recommend not looking at LED lights in operation and suggest eye protection for extended exposure.

This is why you want to wear sunglasses anytime you're in a grow room with HID/Plasma/LED lights on; UV damage to the eye is cumulative and leads to macular degeneration and other problems. My grandmother lived in high and dry Colorado for most of her life, and developed macular degeneration without ever setting foot in an indoor growroom.

/END: topic related safety message. :cool:

ttystikk · May 7, 2012

Texas Kid said:
I am sittin watchin this last round of plants just crawl along, not fattin up or finishin like I usually like so start thinkin about other current setups and past setups for answers. So I start figurin my watts per sq.ft on a bunch of my different setups and this what i got..

#1 setup is (2)600w over a 3x3 table or 1200w/ 9 sq.ft. = 133 watts per sq.ft. or 19,556 lumens/sq.ft. with this setup I can easily pull 3-3.25lbs from 9-16 plants on the 3x3.This is my all time favorite setup for yield, density, finish time, potency all that good stuff. Dual bulb hood used in a 3x3 Hydrohut tent.

#2 (1) 1000w over a 3x3 table or 1000w/ 9 sq.ft. = 111 watts per sq.ft. or 16,111 lumens per sq.ft. perfect for single bulb single hood setup and or in a tent.

#3 (3) 1000w over (2) 3x6 tables or 3000w / 32 sq.ft. = 83 watts per sq.ft. or 13,594 lumens per sq.ft.. This setup is on movers and does alright but could use another 1k to really kickit into gear, but overall decent.

#4 (1) 1000w over a 4x4 table or 1000w / 16 sq.ft. = 63 watts per sq.ft. or 9063 lumens per sq.ft. To me this setup is right at the edge of what you need to really kick it out like on a 3x3. I really like the 3x3 tables instead of the 4x4 all the way around.

#5 (2) 1000w over (2)3x6 and (2)3x3 or 2000w per 54 sq.ft. = 37 watts per sq.ft. or 5370 lumens per sq.ft.. This sucks bigtime, movers almost make it more painful because of the shadow dancin..lack of cash has dictated this setup but still it sucks.

#6 (3) 1000w over a 11x14 room on movers or 3000w / 154 sq.ft. or 19 watts per sq.ft. or 2825 lumens per sq.ft. this is at a buddy of mines and he is complaining about yield, density, and finish times. this setup is doin just well enough to piss you off, not really crawlin but not cruizin either. I am tryin to get 6-8k in there for he real kickin flower action.

So I was curious what everybody else was doin and experiencin..

The sun is roughly 100w per sq.ft. full tilt so that is my basic minimum benchmark for my indoor satisfaction..

Mo lumens, mo wattage, mo betta..

Tex

My room is 16x9, runs two rows of 4 magnum xxxl 'ochos' double barrel style, with a walkway down the middle. It sure seems plenty bright enough for growing desert cactus in there to me, but doing the math; 16x9=144 sq. ft. 8000w/144=55.555 watts/sq. ft.

Suddenly, this appears to slot in just below Tex's 'minimum setup' #4. What am I doing wrong? I rather doubt I'd be able to get another pair of ochos in the length of the room and still have room for venting them at the ends. Even if I did, it would still only bring this stat. up to 70 watts/sq ft. Do I need to consider using vertical bulbs? If so, where would I put them? And then there's the whole cooling angle; I chose sealed and vented hoods because it would reduce my cooling costs and overall footprint in a very quiet residential neighborhood. I doubt my setup could handle a bunch of bare bulbs in addition to the heat load it already sees.

What's worse is that I have been planning to run an experiment with light rotators that cuts this light footprint almost in half- which would put it right at 31watts/sq ft, or even below the #5 setup mentioned above.

I would like to know more about Tex's #4 and #5 setups, specifically his light heights above the canopy and what reflectors he was using.

If anyone has any insights or suggestions about what I might do with my setup- or not- I am interested in all opinions...

Resinable · May 7, 2012

Thanks for the info on the UV, Hogan and Ttystick.

Ttystick, your room has similar dimensions to an 8 by 12.5 I used to work with but is about 25% longer. I had intended to up the wattage of that room from 8.4 thousand to about 10 thousand. Based on that I think you could up your wattage to between 10 and 12.5 thousand. With the layout I used I think you could get to 22+ lbs provided everything was dialed. I used 2 one ton mitsubishi mini splits and one .75 ton unit to cool my room; the condensers on those units are truly almost silent. I used a combo of vented hoods and bare bulbs, see my previous post. Anyway your room's dimensions are perfect for that system . . . I miss that place.

Originally in that 100 sq. foot room I had six thousands (one per the traditional 4 X 4) as I kept adding more and more watts in lights my yields kept going up proportionally which initially surprised me . . .

Also I think the light movers could be a great thing but only if you have a lot of room to work with. In your situation with space being a limiting factor I don't think they would maximize your production.

hogan400 · May 7, 2012

Yrs ago I had 3 600's over 4x8. My buddy liked it so much he did it with 3x1000's, but roached me. I had more plants and the same strain. One thing I noticed was the "penetration" from my 140000 lumen 600's, was not as deep as the 140000 from the 1000's. I know is an arguable point, but he beat me by lbs not grams! After a couple yrs I found 36" of width and penetration is the fucking shit for 1000's. IMHE so much to know. Buy a cheap luxmeter and test it on a 2mo old bulb compared to new and that same 600watt 140k lumens vs the 140k of the 1000 at 3 ft and you will see huge differences!!

Vert there is very little overhead shading so obviously the penetration is better. And now we see vert and overhead. I like how tech is changing... I wonder how the 1500 watters would do in my new garden Im posting in a couple weeks??

ttystikk · May 8, 2012

Resinable said:
Thanks for the info on the UV, Hogan and Ttystick.

Ttystick, your room has similar dimensions to an 8 by 12.5 I used to work with but is about 25% longer. I had intended to up the wattage of that room from 8.4 thousand to about 10 thousand. Based on that I think you could up your wattage to between 10 and 12.5 thousand. With the layout I used I think you could get to 22+ lbs provided everything was dialed. I used 2 one ton mitsubishi mini splits and one .75 ton unit to cool my room; the condensers on those units are truly almost silent. I used a combo of vented hoods and bare bulbs, see my previous post. Anyway your room's dimensions are perfect for that system . . . I miss that place.

Originally in that 100 sq. foot room I had six thousands (one per the traditional 4 X 4) as I kept adding more and more watts in lights my yields kept going up proportionally which initially surprised me . . .

Also I think the light movers could be a great thing but only if you have a lot of room to work with. In your situation with space being a limiting factor I don't think they would maximize your production.

Yes, I read your stadium 'pythagorean' ScrOG report above with interest. As I mentioned, I doubt I can cram another pair of magnum xxxl hoods into the room. I would happily 'settle' for just 8 lbs a run from the room- the kicker being that it's two setups in the same room, so 8 lbs every 4 weeks.

Since the room is currently set up double barrel style, I plan to run two sets of ScrOG screens, one on either side of the walkway. These will be bent to roughly 1/4 round, to help manage canopy to light distance and to add a bit of square footage. I will, with a bit of contortion, be able to get around behind these screens to maintain the plants.

El Cerebro · May 8, 2012

Calling all pythagoreans, be sure to remove the nightly impress from your bed upon arising, and don't ever eat the holy fava bean. You guys know hollow stems are the magical conduit between here and the world of the dead, right? Lemme know when everyone needs another brush-up on ancient greek mystery religions, meanwhile I want see some shit that looks like a topo-map, 3d wall-to-wall with dimpled valleys under beautiful buxom bare bulbs (think egg crate, macro..)

ttystikk · May 8, 2012

El Cerebro said:
Calling all pythagoreans, be sure to remove the nightly impress from your bed upon arising, and don't ever eat the holy fava bean. You guys know hollow stems are the magical conduit between here and the world of the dead, right? Lemme know when everyone needs another brush-up on ancient greek mystery religions, meanwhile I want see some shit that looks like a topo-map, 3d wall-to-wall with dimpled valleys under beautiful buxom bare bulbs (think egg crate, macro..)

Fuckin' smart ass. Wisecrackin' is MY job- and I eat a lot of beans. You have been warned... ;)

Gentle rolling valleys, brimming with verdant panoramas of trichome covered splendor... if this ain't the Elysium Fields, I want a refund!

El Cerebro · May 8, 2012

Oh but I wasn't being facetious, dead serious. Rolling hills of bud, green as the default desktop on them ol Winders computers. Pyramids could be cool too, easier to shape the wire maybe? The actual pythagoreans were a freakish cult, fun reading when you get tired of workin theorems.

Missed that at first, edititore. You made me go look it up. That was the realm of Rhadamanthus. The names back then, really makes a guy jealous

El Cerebro · May 8, 2012

Hey Hogan can you clarify the 36" width part, you mean on the socket to tip axis right? Not really following your other numbers but just not used to thinking in lumens. I've been juggling whether to use 600 or 1k hpsers for the vertical part of a new project (and prob 1k mhers overhead in between). Using 1ks vert bare means bigger plant spacing of course, I'm just playing the space vs light game.

Crysmatic · May 8, 2012

Texas Kid said:
I am sittin watchin this last round of plants just crawl along, not fattin up or finishin like I usually like so start thinkin about other current setups and past setups for answers. So I start figurin my watts per sq.ft on a bunch of my different setups and this what i got..

#1 setup is (2)600w over a 3x3 table or 1200w/ 9 sq.ft. = 133 watts per sq.ft. or 19,556 lumens/sq.ft. with this setup I can easily pull 3-3.25lbs from 9-16 plants on the 3x3.This is my all time favorite setup for yield, density, finish time, potency all that good stuff. Dual bulb hood used in a 3x3 Hydrohut tent.

#2 (1) 1000w over a 3x3 table or 1000w/ 9 sq.ft. = 111 watts per sq.ft. or 16,111 lumens per sq.ft. perfect for single bulb single hood setup and or in a tent.

#3 (3) 1000w over (2) 3x6 tables or 3000w / 32 sq.ft. = 83 watts per sq.ft. or 13,594 lumens per sq.ft.. This setup is on movers and does alright but could use another 1k to really kickit into gear, but overall decent.

#4 (1) 1000w over a 4x4 table or 1000w / 16 sq.ft. = 63 watts per sq.ft. or 9063 lumens per sq.ft. To me this setup is right at the edge of what you need to really kick it out like on a 3x3. I really like the 3x3 tables instead of the 4x4 all the way around.

#5 (2) 1000w over (2)3x6 and (2)3x3 or 2000w per 54 sq.ft. = 37 watts per sq.ft. or 5370 lumens per sq.ft.. This sucks bigtime, movers almost make it more painful because of the shadow dancin..lack of cash has dictated this setup but still it sucks.

#6 (3) 1000w over a 11x14 room on movers or 3000w / 154 sq.ft. or 19 watts per sq.ft. or 2825 lumens per sq.ft. this is at a buddy of mines and he is complaining about yield, density, and finish times. this setup is doin just well enough to piss you off, not really crawlin but not cruizin either. I am tryin to get 6-8k in there for he real kickin flower action.

So I was curious what everybody else was doin and experiencin..

The sun is roughly 100w per sq.ft. full tilt so that is my basic minimum benchmark for my indoor satisfaction..

Mo lumens, mo wattage, mo betta..

Tex

What foot candles at the canopy for #1 through #4? How high are those bulbs above the canopy?

A hortilux 1000W HPS emits 127,000 mean lumens - a more realistic 14,111 lumens/sq.ft. 5000 lumens/sq.ft occurs at 20" height. Interestingly, a 600W HPS with 76,000 mean lumens produces 5000 lumens/sqft at 22" (over 4.5 sq.ft).

I generally aimed for ~65 W/sq.ft. That's a 600w HPS per sq.m, or a 1000W in 16 sq.ft...until I found this thread :)

ttystikk · May 9, 2012

Crysmatic said:
What foot candles at the canopy for #1 through #4? How high are those bulbs above the canopy?

A hortilux 1000W HPS emits 127,000 mean lumens - a more realistic 14,111 lumens/sq.ft. 5000 lumens/sq.ft occurs at 20" height. Interestingly, a 600W HPS with 76,000 mean lumens produces 5000 lumens/sqft at 22" (over 4.5 sq.ft).

I generally aimed for ~65 W/sq.ft. That's a 600w HPS per sq.m, or a 1000W in 16 sq.ft...until I found this thread :)

I have the same questions about his setup- which leads me back to what Squiggly was saying about gathering good data. We as a community could share our datasets much better by just agreeing on a few principal measurements, much like Cap and others (includng myself) have been advocating that everyone use EC to measure solution strength.

El Cerebro · May 9, 2012

ttystikk said:
a few principal measurements, much like Cap and others (includng myself) have been advocating that everyone use EC to measure solution strength.

Ok sounds good, how about micromoles instead of lumens? That one's needed correction for a long time.

Watts/lumens per square foot ?

Watts/lumens per square foot ?

Resinable

El Cerebro

Resinable

El Cerebro

hogan400

Resinable

dankworth

hogan400

ttystikk

ttystikk

Resinable

hogan400

ttystikk

El Cerebro

ttystikk

El Cerebro

El Cerebro

Crysmatic

ttystikk

El Cerebro

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