Deciding on which light to buy.. Sorta of a drag

[JorgeGonzales]

Almost 70% efficient and the cobs cost something like $430 total.

Not to be a dick, but prove 70% efficient. Those @CobKits measurements get real dicey on the low end, and that 70% figure is relative to Cree, but Cree has not provided numbers for the CXB3590 below 50W.

It's all bullshit until this stuff ends up in a sphere, which many people have promised, nobody has delivered.

 

[Stephenj37826]

Remember guys don't get 100% caught up in umol/j. It matters NO.1 where that light hits the canopy and NO. 2 where in the visible and slightly beyond spectrum those photons are. Mostly NO. 1

 

[THE KONASSURE]

if its only 5ft high you might be better off with a few cobs above but mainly go with 1w leds you`ll get more gpw but the units will be much bigger

Induction lights are great for spreading over an area or side lighting if you don`t have much distance but once you go over 100w they can get hot, not as hot as cfl`s get but still

maybe some smd strips could help along with some cobs

 

[MeGaKiLlErMaN]

Not to be a dick, but prove 70% efficient. Those @CobKits measurements get real dicey on the low end, and that 70% figure is relative to Cree, but Cree has not provided numbers for the CXB3590 below 50W.

It's all bullshit until this stuff ends up in a sphere, which many people have promised, nobody has delivered.

I was citing citis 1212 not Cree at all. And all by the calculator.

 

[OneHitDone]

Was budget ever mentioned on this project?

 

[Michiganmeds1982]

Why only 5 foot ceiling? Is that your choice?

 

[JorgeGonzales]

I was citing citis 1212 not Cree at all. And all by the calculator.

OK, again not trying to be a dick, how do I get the calculator to show 70% efficiency?

 

[MeGaKiLlErMaN]

OK, again not trying to be a dick, how do I get the calculator to show 70% efficiency?

*imagination* lol no but that was here. You can ask @CobKits ive seen the quote a few places... It's the most cost efficient solution too.

https://www.rollitup.org/t/all-things-vero.851330/page-121#post-12957854

 

[CobKits]

calculator is just a front end for the data generated by the citi tool, so it should give you same data as citi tool

the only 70% measurements we have are estimated from ppfd/W @ 12" data relative to DB cree 60% at 35W. also thats assuming the same LER for 4000K 80CRI as crees 324 for 4000K 70CRI. what number do you have for that jorge? may be irrelevant as my relative measurements measure par not lumens

 

[CobKits]

heres the raw data. dont trust the absolute lowest current data as its getting a 2 umol free advantage from stray ambient light. accounting for this at 6W the CXB is prob topping out at 67.5% and the 1212 @ 68.5%. ill try to do some low current tests in absolute darkness, but again, take the test for what its worth. PPFD at 20W and up i have good confidence in, at that point, ambient light is well under 1% (and more importantly same for all chips so negatable on a relative basis)

 

[JorgeGonzales]

calculator is just a front end for the data generated by the citi tool, so it should give you same data as citi tool

the only 70% measurements we have are estimated from ppfd/W @ 12" data relative to DB cree 60% at 35W. also thats assuming the same LER for 4000K 80CRI as crees 324 for 4000K 70CRI. what number do you have for that jorge? may be irrelevant as my relative measurements measure par not lumens

PAR is PAR, LER is irrelevant unless you are comparing lumens.

The biggest source of error might be your sensor's nonlinearity combined with the relatively large spectrum differences between Citizen and Cree with those two cobs. Probably not that big though.

 

[CobKits]

i wanted to get a 4000k 80cri cree but even cutter doesnt stock em, prob cause the bin addicts dont want em

PAR is PAR, LER is irrelevant unless you are comparing lumens.

so youre saying throw away the online simulators for our purposes

 

[CobKits]

Not to be a dick, but prove 70% efficient. Those @CobKits measurements get real dicey on the low end, and that 70% figure is relative to Cree, but Cree has not provided numbers for the CXB3590 below 50W.

It's all bullshit until this stuff ends up in a sphere, which many people have promised, nobody has delivered.

yeah i dont even like to do the conversion to efficiency but its unfortunately somewhat necessary to translate the data to people that use it as a point of reference. ill stop publishing data below 10W as well

 

[sixstring2112]

. ill stop publishing data below 10W as well

i was gunna ask why were even talking about eff # at 10 w and below,like how many of us will ever run chips that soft? cant even remember seeing a 100ma driver with any kind of power behind it to run strings of chips but maybe they exist ?

 

[JorgeGonzales]

so youre saying throw away the online simulators for our purposes

Thats why I made the charts that converted the simulator's lumens to umol/J and efficiency.

 

[CobKits]

i was gunna ask why were even talking about eff # at 10 w and below,like how many of us will ever run chips that soft? cant even remember seeing a 100ma driver with any kind of power behind it to run strings of chips but maybe they exist ?

easy with constant voltage drivers. a hlg-185-36 will run 20 chips at 10W

 

[puffenuff]

I think NextLights are pretty neat, but they were not designed to be HPS-like, and neither HPS or LED is anything like the sun. It's completely inaccurate.

There's a couple other accompanying paragraphs and graphs that didn't get quoted here, that when taken into consideration, the point they were trying to convey makes more sense. Peace

 

[tomate]

Thats why I made the charts that converted the simulator's lumens to umol/J and efficiency.

...and in my opinion this is the only trustworthy data source that can be used to make comparsions.

 

[JorgeGonzales]

...and in my opinion this is the only trustworthy data source that can be used to make comparsions.

Well comparing COBs relative to one another is still valid. Especially if the differences are large enough and consistent enough in a well-designed testing setup to show a pattern. And we've seen the same pattern from a handful of testers now.

@CobKits uses a wide-bandwidth, relatively flat PAR sensor centered under the COB from a fixed distance. This seems to fit the definition of well-designed rig, as long as you realize you are also testing thermal resistance, heatsinks, and seeing errors from sensor linearity, and tiny differences in centering and height.

Still, there is a pattern.

 

[CobKits]

thread is off the rails...

anyway is it worthwhile to test a bunch of different citi color/cri combos to confirm relative relationship of your umol/J numbers?