I searched Spectroradiometers.
It looks like it generally measures all the wave lengths a light source puts out using the amount of lumens each is and tells you what percentage each wave length is and accordingly divides the watts used to produce each wave length to tell what watt per wave length that that light source is.
Actually it looks like an all in 1 meter.
Can tell you LUX,LM,and Par for different lighting applications for each wave length produced by the source,not just wave length percentages.
But maybe the one I looked at was a deluxe model or something.
It looks like it can give you LUX,PAR and LM. for each individual wave length...uses watts as a measure...
Watts per meter etc.
More snake oil salesman fodder in my opinion since I see most nobody either using that instrument or publishing data from using it on their grow panels or LEDS.
You are still misleading people saying Watts matters when buying an LED or Panel since they don't have access to the info that the Spectroradiometer measures.
A 30 watt LED panel uses 30 watts,it's no indication of wavelength lumen or anything else.
They aren't advertised as 10watts of 660nm,1watt of 430nm etc.Which is what that meter tells you.
Watts still is a unit of measure found by multiplying Amps. X Volts.
Not a unit for measuring Lm,Wave Length or anything else.
The only tools the average person has to go by are Wave length the seller says their LEDS/panel are,the Lumens they are rated at and the watts the whole panel uses to run.
I don't know how much of each red wave length a specific LED puts out in any specific wave length but a CD tells me if the red or Blue band is bigger than the other color bands.
I'm in the ball park.
If I measure the LUX under my plants I can tell that the light my panel is putting out is bright enough in general.
Using those 2 measuring devices tells me pretty much all I need to know.Or have access to as far as measuring my LEDS.
I know already that any LED puts out varying amounts of higher and lower wave length of light also so if I can't find LEDs with a specific wave length I've probably got it anyway.If it's close to the main/dominant wave length of that LED.
Then there is the fact that Drivers don't put out the same out put 100% all the time and LEDS are VERY sensitive to voltage changes as far as wave length is concerned.
A very slight change in voltage throws the reading by that do dad off ,gotta take a reading using your grow enviornment to really know what you have going on.
660 might not be dominant anymore.Depends how dominant it was in the first place.Was it 1% higher to make it dominant or 50% higher which would make the sellers readings still good.
Like with car adds,your mileage may vary...
Add to that LEDS are also heat sensitive as far as output goes and a hot day or room temp. throws everything off.
So in my opinion,all a person can really do,outside of a lab,is stay in the ballpark.
Thus making almost any way you want to measure your panel isn't that much different than any other.
From what I've read the Spectroradiometer is mainly used to measure light for laptops,room lighting etc. to design light sources that need to meet certain specs. without wasting energy or meet specific requirements.
Not that important for growing peppers.
Plants don't generally mind if they get 660nm or 661nm.
It does sound like a better tool, if you have it,to design any kind of lighting that has to meet certain specs. or the light source won't work at all for that application.
But the fact is,right now not many people use that do dad when they design grow panels ,so unless you are buying from a specific company ,you are out of luck.
If you are making your own panels it's just more useless info unless you want to crowbar open your wallet and buy the do dad.
I think in general for the DIY er the thing to do in general is get as many wave lengths in plant usable wave lengths in as high a Lumen rating as you can find and use them.
Also try and get as many of the same wave length rated LEDs from as many different lots and companies as you can.Not all 660nm LEDS or whatever are the same.
My point is,I want to cover as many wave lengths of plant usable light as I can.
Different lots of LEDS will put out a lot of wave lengths in lesser amounts that you can't buy a specific LED in for those wave lengths.
But plants might use them.
With other LEDs puting out these wave lengths there seems to be enough of them combined ,in the right amount to grow my peppers.
I try to get as close to real sunlights plant usable wave lengths as possible.
It's not possible,I don't think ,but I can get enough different wave lengths that my plants grow pretty well so far.
To overcome any light penetration problems with bigger plants I put LEDs both above,horizontally and vertically around my plants.
5mm and 10mm LEDS work good for that.5mm are dirt cheep but you have to use a ton of them.
A 3X4 perf board holds 100-120 of them and takes an hour to solder.
So far 5mm LEDS come in the most wave lengths and angles too.
They aren't very bright and you need a lot of them...
I also like 1 watt LEDS because I can put as many different wavelengths as I can find on a 8X8 or 16x16in sheet of 1/8th inch thick Aluminium and not have heat problems or have to cool them.
3 watt ones I have to space them farther apart and that means less wave lengths will overlapspamus I have to put a fan for cooling them.
There is a method to my madness.
I think the more wave lengths on a panel the better.
At least my plants grow better under a dozen wave lengths than they did under 4 - 6 wave lengths.
My thinking is to use as many different wave lengths between 400nm and 480nm Blue and as many between 615nm and 680nm as I can find in each panel.
I read about yellows etc. but when I look at my CD I see those colours in lesser amounts being given off so I think I'm covered there.
I also read that LEDS in certain plant usable wave lengths put out some UV and infa red which they say plants can use but in very small amounts.
So they probably get enough of those wave lengths already,no need to put LEDS for them on my panels.
Actually I've read that as far as UV goes,you should not look at some blue leds because there is enough uv produced to cause eye damage from constant exposure.
10mm are what I've been playing with lately.
More expensive but as bright as 1 watt stars.
Easier to assemble on a 7X12 perf board.
Covers a LOT more area too.
Only problem is they don't come in many wave lengths.but that is quickly changing.
Doesn't look like we agree on the lum. watts thing but it's always interesting to discuss different points of view etc.
It's never a waste of time to discuss things it often leads to new ideas.
I just found a meter that looks palm sized for measuring chlorophyll.
A measly $1295.
It was suggested as an instrument to go with your $4000 - $5500 do dad for measuring your light source.
$4000+ buys a lot of LEDS.
As a side note.
Do you happen to have a link to how much of each plant usable wave length is in the sun or how much of each wave length a plant needs or uses?
Not just pot plants.All plants in general.
I assume you do or even knowing the amount of each wave length your light source puts out wouldn't matter.
Wouldn't know what you need of any of them in your grow light.
Only thing I've found was low red to far red is 1.2 - 1 in sunlight.
Never found anything on the specific different wave lengths.
Nasa used a 6-8 to 1 ratio of red to blue in their experiments and used white too.Don't know which K the white LEDs were.
How much of each wave length seems hard to find.
All I see out there are people hawking their goods saying their wave length combo is best with no real data to support it.
Just a bunch of fan letters in general.
A few places quote choice parts of some study, out of context , but that's about it as far as what I can see.
Also it looks like most of the do dads that are made specifically are for LED manufacturers so they can test a few of their lots of LEDs to see if they got the dominant wave length right.
The do dad with the most bells and whistles had to be plugged into your computer.
It must be REALLY expensive,you gotta write for a price.
That usually means it's so expensive they gotta talk you into buying it as opposed to the ones with the price next to the specs.
I just checked out the sites products and they brag about the PAR of their panel/grow light.http://www.lumigrow....led-grow-light/
Full PAR Spectrum-what the heck is that?
OOOPS PAR again.http://www.lumigrow....led-grow-light/
OH NO PAR again.http://www.lumigrow....ed-strip-light/
From the same guys who say anything other than watt is crap.
If it looks like snake oil,feels like snake oil and tastes like snake oil it just might be snake oil.
I hear snake oil is really good for lubrication to get $ to slide right out of your wallet real easy.
The more $ you charge,the more snake oil you need to sell the product.
I'm not saying their lighting is junk.
Just that it probably isn't any different than a lot of other companies out there.
They are selling a product and advertise or print whatever makes them look better for selling said product.
They use watts as they should be used in their data about their grow lights.
Compare watts used by other light sources to produce X amount of PAR.
They actually don't say what the products PAR is,just that some gobbledy gook about PAR spectrum.Sounds like nonsence/saleman speak to me.
They never say,that all LEDS at the factory are tested with your do dad to check for quality as far as making sure their different lots of LEDS puts out the right/same wavelength as dominant and that actually the average person can't find info whether that batch of LEDS was dominant by 1% or 50% (whatever) which would be the only reason you would want to know the percentage of a wave length a light source puts out using however many watts to do it.
The only thing your do dad does is make sure a light source is up to specs because it can zero in on specific wave lengths and tell you the watts it takes to produce that wave length in that specific light source.
Maybe the light meters aren't as accurate that measures Lumens , Lux or PAR but since they use PAR you can say that PAR is accurate enough.
The only stuff I've read about Lux etc. being inaccurate is from people selling something and miss represent everything else.
They never say Lm,Lux or par are wrong.Just that the meters can't measure some of the wave lengths that LEDS CAN put out.
They all use generalities-High red High Blue or whatever.
As far as I can tell they might be great at measuring any Wave length a plant uses,just not some of the ones an LED puts out but isn't of concern as far as growing plants in general.
Common sense tells you that depending on the quality of a LED if it's rated at 660nm as dominant it'll be at least 50+% that wave length.
So if you want to turn it into watts you just divide the watts your led is rated at by 50%.If the LED puts out more than 50.1% you are just better off as far as that wave length is concerned,the lED is more efficient at putting out that wave length.
From what I understand,Most LEDS if not all can only vary 2nm +/- from the dominant wave length depending on physical and electrical variations in how it is made.
They all put out other wave lengths but in much smaller amounts.
A cd with a LED in a dark room will tell you that.
They ( company pushing the snake oil) might(which I doubt) test their LEDS so Dominant means 70% dominant. and then can claim their LEDS are better than Lets say a Chinese made one that is only 50% dominant in whatever wave length.
But you don't know.
They are probably like any other grow light supplier.They use whatever LEDS their supplier or suppliers give them.
And let the advertising Dept. sell them in any way that works best.
Can't dazzle them with brilliance,baffle them with B.S.
The more I read about your do dad, it is only good for stuff that needs to have specific applications for commercial use where the wave lengths HAVE to be exact.
Peppers don't fall in that catagory.
They aren't worth the cash to mess with hassling to give them premium lighting.
Since Pot in CA. is legal and the cash it brings in is big.I could see a person wanting to give their plants perfect growing conditions.
I only grow non bell peppers,nothing else.
They aren't that fussy about having only specific wave lengths.
They bud whether they are under Fluorescent light or 660nm LEDS.
Yes they might do better under certain wave lengths but it's a crap shoot.
Manzanos really love 650nm - 662nm but other peppers like more 625-627nm.Some like lots of 470nm others don't care.
Some don't care what they get the most of as far as what I've grown in the last 3+ years.
A side note,did you Know that to get white light LEDS combine red,blue and green to get high lumen white LEDS?http://focs.eng.uci....llumination.pdf
Kinda cool read even though I don't get all of the tech stuff 100%.
But it does make me think about using white LEDS as a possible light source for grow lights.
Problen I see is most LEDS are too high or low K to cover what I can get from using red and blues.
I really think it'll end up being a supply and demand type thing.
Once the producers get enough demand for LEDS that are in the 5000-6500 K range they will make them.
Right now I see LEDS in the 2000-3500k or 6500-7500k range.
Both aren't in the sweet spot that fluoros now produce for a lot less $.
I hope you don't think I'm getting on you for your ideas etc.
I'm not trying to piss you off.
Ya I've been told I'm too blunt or whatever.
I do enjoy our exchange of ideas.
I see things as I see them and post accordingly.
I'm not trying to mess with you or your view of what you base your ideas on.
The purpose of this post is to exchange ideas that WILL open doors that will help people get an idea about how to look for things to form their own opinions.
My ideas are worth just about what it cost anyone to read them,right or wrong,judged by the reader doesn't matter as long as it caused the reader to search out more info about this subject.
I only know or think I know stuff mostly from Trial and error.
I don't consider I've wasted a cent because I've learned from assembling my LEDS.Reassembled a lot of them too when the panel sucked that I made.
All LEDS I've bought were re used again for other panels.
I am not into buying a growlight.
I want to build one that works for ANYTHING I want to use it for.
It has taken me 3 years but I have found what works for the way I need them to work the way I need them to work.
I have full grown plants that mostly get LED light.
It's not as hard to do with LEDS as People/so called experts say it is.
One thing I found was that LEDS can be too close.
Since I use a lot more Wave lengths per panel,the sweet spot where everything overlaps is a lot farther away than I read about on the net.
Yes 10mm LEDS with tighter angles are probably better for distance but with 1 watt stars 18 inches is the least I want my LEDS away from my plants.
That is using 50 1 watt LEDS on a 8in X 16in. sheet of metal.
Your mileage WILL vary,if you use higher quality LEDS you'll get better results.
I buy only Cheap Chinese or Hong Kong LEDs(which are probably the same stuff a lot of the other people are selling on their american made panels).
I don't take info from a site that sells LEDS for growing plants as anything more than something to check out as far as science or whatever you want to call it goes.
Yes a lot of the commercial sales pitches have given me a lot of clues as far as what to research but they never or almost never gave all the facts about anything unless it sells their product.
Not everything I read on the net is fact until I find and read the research they are mostly miss representing to sell their product most of the time.
Edited by smokemaster, 19 May 2012 - 09:30 PM.