IF you are new to LED and want help choosing what to buy, POST HERE!

az2000 said:

Getting back to Chinese fixtures using epi-unknown chips (and the "decision tree") it sounds like the only use case is a short grow space where CMH isn't an option, the grower isn't willing to invest in a better light that can be used in said space, and doesn't want the modest DIY requirement of rigging up more efficient LED lightbulbs.

Sounds like you'd apply that reasoning to any LED (epi-unknowns or high-quality Cree, Osram, et. al.). At least you didn't qualify your recommendation above. Why is that? I think you said in another thread you feel LED technology is evolving too fast to invest significantly in whatever the leading chips are at any given moment? That seems valid (unless they have high electric costs, heat issues, etc., that might justify the expense.).

I'd like to hear @couchlock's opinion. Can he think of any other use cases where Chinese epi-unknown fixtures would be a valid recommendation?

Just trying to understand all the bad vibes from people who feel Chinese fixtures get a bad shake on this forum. So far, it sounds like you're decision tree is rather short. Just wondering if @couchlock agrees, or can explain more branches to the tree.

Click to expand...

I bought 8 300 watt Chinese LED 11 Band LEDs. Ive never seen growth the way these are giving me. Cheap yes, one of them I had to change the driver on and the other I changed a fan. So far though the price Ive paid for those 8 on dhgate.com has far exceeded what I was expecting from cheap LEDs. Plants are enormous but short and bushy, trich production is far better than HPS. Stretch is half as much as HPS. Smell, stickiness, and denseness is far better than HPS alone.. Im never using anything other than LEDs ever again. For 90 dollars a piece for a 11 band 300watt, I think they did a fairly decent job. They all still work and I had to make 35 dollars in repairs to one of them and a 10dollar fix on the other so far. I think they do pretty good for the price in my honest opinion.

Cpappa27 said:

I bought 8 300 watt Chinese LED 11 Band LEDs. Ive never seen growth the way these are giving me. Cheap yes, one of them I had to change the driver on and the other I changed a fan. So far though the price Ive paid for those 8 on dhgate.com has far exceeded what I was expecting from cheap LEDs. Plants are enormous but short and bushy, trich production is far better than HPS. Stretch is half as much as HPS. Smell, stickiness, and denseness is far better than HPS alone.. Im never using anything other than LEDs ever again. For 90 dollars a piece for a 11 band 300watt, I think they did a fairly decent job. They all still work and I had to make 35 dollars in repairs to one of them and a 10dollar fix on the other so far. I think they do pretty good for the price in my honest opinion.

Click to expand...

What kind of watts per sq ft do you run? What kind of grams per watt?

Cpappa27 said:

I bought 8 300 watt Chinese LED 11 Band LEDs. Ive never seen growth the way these are giving me. Cheap yes, one of them I had to change the driver on and the other I changed a fan. So far though the price Ive paid for those 8 on dhgate.com has far exceeded what I was expecting from cheap LEDs. Plants are enormous but short and bushy, trich production is far better than HPS. Stretch is half as much as HPS. Smell, stickiness, and denseness is far better than HPS alone.. Im never using anything other than LEDs ever again. For 90 dollars a piece for a 11 band 300watt, I think they did a fairly decent job. They all still work and I had to make 35 dollars in repairs to one of them and a 10dollar fix on the other so far. I think they do pretty good for the price in my honest opinion.

Click to expand...

That is exactly as I would describe my plants under the diy whites. I don't know about the better than HPS ... part but bushy tricy, happy green, lovin life. How much? Have a link?

az2000 said:

What kind of watts per sq ft do you run? What kind of grams per watt?

Click to expand...

Can we add gram/sqft as another measure? That is honestly the one that matters most to me.

5'x10' room 2400 watts of LED, 400 watt Fluoro (8 300 watt 11 band LEDs) and 1 400 watt 4'x2' 8 bulb T5

Cpappa27 said:

5'x10' room 2400 watts of LED, 400 watt Fluoro (8 300 watt 11 band LEDs) and 1 400 watt 4'x2' 8 bulb T5

Click to expand...

That's 64w per sq. ft. That's quite high by comparison to high-quality LED. (Are you telling us the actual watts used, or the rated watts?).

Are you pulling > 7 lbs from that space? (3200 g?)

az2000 said:

That's 64w per sq. ft. That's quite high by comparison to high-quality LED. (Are you telling us the actual watts used, or the rated watts?).

Are you pulling > 7 lbs from that space? (3200 g?)

Click to expand...

My new room will run 2200w (actual) of epistar emitters and 200w in tanning bulbs. It is 8x4. 7700 lumens per square foot. Absolutely ideal lighting levels short of using CO2. I'm not going to compete in grams per watt, I lose, I admit it. I think I can compete and maybe win in grams per SQFT. Want to try?

Edit: It's actually more like 7000 lumens per sqft, the 7700 was with 2400w, I removed 200w for a mom area.

Greengenes707 said:

So you have never flowered anything under them yet???...and you're saying they are the coolest and best???
And you say 2 of the 750's...pulling 860w...and costing 2300$+... will produce more than my 1000hps solis tek(consistently 700-800g), my apache at600(last harvest ~750g-800g+ per light), and my DIY(~1g/w)???? What about their 1000w version. would that go head to head with any of the lights I use????

Click to expand...

JimmyIndica said:

Click to expand...

I have under the 3w ones, not the 30w ones. So half of my system is tested, half not.

I'm high, only read first sentence.

nomofatum said:

My new room will run 2200w (actual) of epistar emitters and 200w in tanning bulbs. It is 8x4. 7700 lumens per square foot. Absolutely ideal lighting levels short of using CO2. I'm not going to compete in grams per watt, I lose, I admit it. I think I can compete and maybe win in grams per SQFT. Want to try?

Click to expand...

That's 75w sq. ft. I'm not sure how the subtle twist in the topic affects things. If you can produce 1g/w with 35-40 w/sq ft of high quality LED, wouldn't that result in more grams per sq. ft? I'm not terrific at math. But...

I'd like to understand cpappa's paramaters because he's pleased with his Chinese epi-unknown fixtures. I want to understand in more objective terms why. I think that gets to critical comments about these fixtures. Owners will say they're pleased with the results of Chinese lights, plants look healthy, etc. But, measurable results don't look so persuasive when fixtures using high-quality LEDs produce more weight for less electricity/heat. Owners of those lights think their plants look healthy too.

Just trying to reach a conclusion with cpappa to see how his contribution might affect the "decision tree."

az2000 said:

That's 64w per sq. ft. That's quite high by comparison to high-quality LED. (Are you telling us the actual watts used, or the rated watts?).

Are you pulling > 7 lbs from that space? (3200 g?)

Click to expand...

I never weight my product cause its for my moms medical use since the doctors here are Nazis and cant get her a medical cars. The grow I have going no I will harvest soon and I will update you on what the weight is. I never weighed anything cause I thought it useless since Im not selling and didn't care what I got, as long as I got her her meds. I will buy a scale and give pics and a reading on what I get for weight .

I just go by what I see and these leds gave me a shpoter bishier plant with super tight nodes and super tight bud sights. Im excited to see what I get from this.

az2000 said:

That's 75w sq. ft. I'm not sure how the subtle twist in the topic affects things. If you can produce 1g/w with 35-40 w/sq ft of high quality LED, wouldn't that result in more grams per sq. ft? I'm not terrific at math. But...

Click to expand...

No, that would result in less grams but more grams per watt.

Example:
"High Quality" 40 w/sqft at 130lm/watt = 5200lm sqft
"EpiStar" 75 w/sqft at 100lm/watt = 7500lm sqft

You can reasonably expect the 75w/sqft system to produce 44% more weight. (or at least it's getting 44% more light energy)

If we pretend the 40w system produced 100g and the 75w system produced 144g that would make the 40w system have 2.5g per watt. and the 75w produced 1.92g per watt. Remember fictional numbers just to demonstrate the math. I pick the 75w choice and my extra 44g.

nomofatum said:

If we pretend

1. the 40w system produced 100g (2.5g/w)
2. the 75w system produced 144g (1.9g/w)

Click to expand...

Isn't that what I just said? Replace the lights producing 75w/sq ft with the lights producing 40w/sq ft and now you're producing 32% more per sq. ft.

az2000 said:

Isn't that what I just said? Replace the lights producing 75w/sq ft with the lights producing 40w/sq ft and now you're producing 32% more per sq. ft.

Click to expand...

No, the 75w one produced 44% more per sqft. the 40w one produced 32% more per watt. So if you are concerned about SQFT more than watts consumed the better of those two choices is the 75w.

Total weight the 75w/sqft 100lm/watt system wins at 44% more

Let me do that again to be absolutely clear

System #1: 75w per SQFT, 100 lumens per watt = 7500 lumens per SQFT
System #2: 40w per SQFT, 130 lumens per watt = 5200 lumens per SQFT

That is 44% more lumens per SQFT.
This is the best available measure of light energy available across bulb/emitter types.
It is reasonable to assume with 44% more energy a plant could produce up to 44% more weight.

In a world where system #2 got 1.1g/w for a total of 44g per sqft system #1 would get 63.36g per sqft or .8448g/w.

az2000 said:

Isn't that what I just said? Replace the lights producing 75w/sq ft with the lights producing 40w/sq ft and now you're producing 32% more per sq. ft.

Click to expand...

Oh, you mean run 75w of Crees or 130lm/watts version emitters right? The only problem with that is that you would be putting out too much light energy and burn the plants without upping the humidity and CO2 levels. Anything over 8000lm/sqft needs constant attention or they go from thriving to dying in hours. The other issue is the fact that they cost much more initially and it takes some time for that cost to pay off. If done DIY we are talking about 8x the cost for 130lm/w emitters vs 100lm/watt emitters.

You can't produce any more bud than the 75w/sqft system in theory. You can produce just as much using less watts and the same lumens/sqft. 57.7w/sqft would be the sweet spot for a 130lm/watt emitter, aka 7500 lumens/sqft.

It doesn't matter what light you have it's the light energy. Hit 7500 lumens on mostly the target spectrums (3000k, 6500k) and you are in the sweet spot. The watts only matter for the electric bill.

Newbie growers shouldn't start at 7500lm/sqft though. 5000lm/sqft should be more likely to be successful for first 2-3 grows. More attention is required for higher lumens/sqft. 10,000 is the max used commercially, that is under CO2 and humidity in the 90-110f temp range.

nomofatum said:

Oh, you mean run 75w of Crees or 130lm/watts version emitters right? The only problem with that is that you would be putting out too much light energy

Click to expand...

Yes, that's where I was going. I'll have to ponder that Chinese epi-whatever fixtures are good for throwing a lot of light at something with minimal initial investment. The argument against them is that they're energy inefficient. If a grower seeks to eek out maximum yield from a space (despite diminishing returns for the electricity used), then yes, those Chinese epi-whatever fixtures are a good way to do that.

However, we get back to the common suggestion that a CMH can produce more par watts with less electricity. That's always been a "decision tree" branch which you didn't object to previously. Are you objecting now?

I.e., if throwing electricity at the plant is not a concern, CMH is still supposed to be better at that than Chinese epi-unknown fixtures.

That would be my response to @Cpappa27. It's cool he's producing enough for his mom's use by overdriving his plants as he is. He could do it with less watts, less heat if he paid a lot for electricity (or lives in a hot climate). But, If that's not a factor, CMH makes more sense. More PAR for the same watts/heat.

az2000 said:

Yes, that's where I was going. I'll have to ponder that Chinese epi-whatever fixtures are good for throwing a lot of light at something with minimal initial investment. The argument against them is that they're energy inefficient. If a grower seeks to eek out maximum yield from a space (despite diminishing returns for the electricity used), then yes, those Chinese epi-whatever fixtures are a good way to do that.

However, we get back to the common suggestion that a CMH can produce more par watts with less electricity. That's always been a "decision tree" branch which you didn't object to previously. Are you objecting now?

I.e., if throwing electricity at the plant is not a concern, CMH is still supposed to be better at that than Chinese epi-unknown fixtures.

That would be my response to @Cpappa27. It's cool he's producing enough for his mom's use by overdriving his plants as he is. He could do it with less watts, less heat if he paid a lot for electricity (or lives in a hot climate). But, If that's not a factor, CMH makes more sense. More PAR for the same watts/heat.

Click to expand...

I think the decision tree is more complex than you think. CMH again is a more expensive initial investment than the Epistar for DIY. So we need two decision trees, a DIY tree and a no-DIY tree.

nomofatum said:

I think the decision tree is more complex than you think. CMH again is a more expensive initial investment than the Epistar for DIY. So we need two decision trees, a DIY tree and a no-DIY tree.

Click to expand...

Ok. So, it sounds like we've filed in the "decision tree" a little further. For someone like @Cpappa27, CMH would have been the appropriate branch.

Still like to hear what @couchlock thinks; if he sees other conditions that would lead to Chinese epi-unknown fixtures.

It will be interesting to hear the DIY branch unfold. In what cases less efficient Epistars are desirable. I can't contribute to that. But, I look forward to seeing the different views.