Do lumens really matter? Do they add up? Lighting experts apply within

[macrael]

i am not an expert but when i bought my SUNBLASTER™ T5 24 Watt High Output - 6400K(http://sunblasterlighting.com/t524.html) was supposed to be equal to 125w or 150w bulb but i just noticed that degrees kelvin is more then most hps or metal halides most range from 2100 to 5500deg. k. maybe thats why my babies are so pale hmmm. also im am not an expert like i said i dont know if there ceramic or not but almost all the mh lights have way more then 50k lumens from the chart that i seen from que pousse but then theres another section where they don t even show the lumens (there marked with a ?) i am not saying your wrong just stating info that i found

 

[macrael]

Let me get you pic right 50000/10=5000
5000/54=92.6

so its 92.6 lumens per watt for a t5ho ist that more than the Mh or is that a typo in the pic

i think they went with options that best suited there needs cause my t5 is around 2000 lumens and its 24w comes out to 83.3 lumens /w

 

[plaguedog]

The reason why they show the lumens per watt is to show efficiency, not the power of the bulbs. So yes, t5 floro are more efficient with lumen per watt then MH.

 

[plutomoney]

i am not an expert but when i bought my SUNBLASTER™ T5 24 Watt High Output - 6400K(http://sunblasterlighting.com/t524.html) was supposed to be equal to 125w or 150w bulb but i just noticed that degrees kelvin is more then most hps or metal halides most range from 2100 to 5500deg. k. maybe thats why my babies are so pale hmmm. also im am not an expert like i said i dont know if there ceramic or not but almost all the mh lights have way more then 50k lumens from the chart that i seen from que pousse but then theres another section where they don t even show the lumens (there marked with a ?) i am not saying your wrong just stating info that i found

Im using T5's grow to harvest and that 24w t5 is not a high output its a regular t5 t5ho are 54w. The temp range is for the spectrum of light used light is a different colors beacuse of the kelvins the t5ho are a little bit more not by much than regualr t5's

 

[plutomoney]

The reason why they show the lumens per watt is to show efficiency, not the power of the bulbs. So yes, t5 floro are more efficient with lumen per watt then MH.

I was trying to show the picture is wrong 90 lumens per watt and 400 watt is like 36k lumens not near 50k lumens at the coop near me they have a grow by grow with MH and t5ho(for Veg) and the t5 has tighter nodes seems denser the experiment was done with indicas and the Mh had the same results as a 8 bulb t5ho on the sativas the t5 had an advantage. Im glad I bought the t5s because a week ago i seen the comparison. Im not doggin a mh but that pic makes it seem like its the best since sliced bread.

 

[macrael]

Im using T5's grow to harvest and that 24w t5 is not a high output its a regular t5 t5ho are 54w. The temp range is for the spectrum of light used light is a different colors beacuse of the kelvins the t5ho are a little bit more not by much than regualr t5's

sorry just went to check on the site of the type of flor. that i am using i put a link in my other post and it states that go check your self i haven t tested it but it is written there that the 24 and the 54 w have the exact same degrees k. the only difference was in lumens take a lookat the site there suppsed to be a new type on the market
here it is again and you can check between the three different sizes they have in ho floros http://sunblasterlighting.com/t554.html

 

[macrael]

i just use what i have theres many different methods that do work. if theres somebody that drinks coke there whole life you think you can get them to change to pepsi then theres other people that drink a variety of things not just one refreshment. i havent seen anybody produce huge colas with leds or florescents or cfls but that doesn't mean i dont believe it can t be done who knows maybe leds will be the future but for now hps and mh and ceramics produces the best results that i have seen another thing i belive is that most mh are better for vegging and most not all hps are better for flowering and most ceramics are kind average between both worlds of light although theres lots of things that come into play here such as different producers(companies) and different combinations of light spectrums there is not one bulb that can completely imitate the sun that i know of. i was under the impression that the more lumens the better ? or is it more lumens =to more heat. i give up i aint a scientist im just going to have fun growing my little buddies lol cheers everybody

 

[plutomoney]

i just use what i have theres many different methods that do work. if theres somebody that drinks coke there whole life you think you can get them to change to pepsi then theres other people that drink a variety of things not just one refreshment. i havent seen anybody produce huge colas with leds or florescents or cfls but that doesn't mean i dont believe it can t be done who knows maybe leds will be the future but for now hps and mh and ceramics produces the best results that i have seen another thing i belive is that most mh are better for vegging and most not all hps are better for flowering and most ceramics are kind average between both worlds of light although theres lots of things that come into play here such as different producers(companies) and different combinations of light spectrums there is not one bulb that can completely imitate the sun that i know of. i was under the impression that the more lumens the better ? or is it more lumens =to more heat. i give up i aint a scientist im just going to have fun growing my little buddies lol cheers everybody

The 24w are the 2 footers you are right different strokes for different folks the temperture is just for the spectrum of light given off. And to get huge colas you need a smaller light source because a 1kw mh thats 18' long wont concentrate the light for huge colas the heat in kelvins are just for spectrum range sorry about the miss spelling english is my 3rd language. Funny because i was born here in the states.

 

[VividDane]

according to this information there is no general conversion factor between lumens and PAR. That is if im reading it right.

I posted this in another thread but I think it fits in here just as well.

The chart below will give people a good impression of how much PAR is being emitted from various std. light-sources.

How can I evaluate the effect of different light sources on plant growth?

The Photosynthetically Active Radiation (PAR) measure of radiant power is important in evaluating the effect of light on plant growth.

In 1972 it was shown by K. McCree (Agric. Meteorol., 10:443, 1972) that the photosynthetic response correlates better with the number of photons than with energy. This is expected because photosynthesis is a photochemical conversion where each molecule is activated by the absorption of one photon in the primary
photochemical process.

PAR is defined in terms of photon (quantum) flux, specifically, the number of moles of photons in the radiant energy between 400 nm and 700 nm. One mole of photons is 6.0222 x 1023 photons (6.0222 x 1023 is Avagadro’s Number).
The Photosynthetic Photon Flux Density (PPFD), i.e., the photon irradiance, is expressed in moles per square meter and per second (formerly, Einsteins per square meter and per second).

There is not a general conversion factor between photon measurements and energy or light measurements for broad band radiation. However, a specific conversion factor can be determined for a given spectral power distribution, e.g., a particular light source. This is of practical value because conventional lighting calculation techniques can be used for design of plant growth areas and because color corrected light or illuminance meters can be used to measure PAR values.

Some plant scientists want a conversion for the photon flux in the 400 nm to 800 nm band although it is not the standard PAR metric (see CIE Publication 106, Section 8, 1993); this conversion also has been included.

Source: http://openwetware.org/images/e/e8/Conversion_lux.pdf

The way I understand the note of no general conversion factor is that the PAR emitted can not be sized by a given lumens output, instaid you have to calculate the total moles for the grow-area space vs. light-source, wich is somewhat different from the way we measure lumens. So, no direct relation between lumen and PAR. Please correct me if I'm misreading things.

 

[bigv1976]

Ok so if lumens dont add up the all the people growing with 26 watt CFLs are only giving there plants however many lumens come from 1 bulb?

 

[Kphlash]

Ok so if lumens dont add up the all the people growing with 26 watt CFLs are only giving there plants however many lumens come from 1 bulb?

Get lumens out of your head as the main factor, look for PAR. Lumens can also be equated with heat. More lumens = more heat

lots of analogies have been used basically 1 candle reaches 40ft, 2 candles next to each other will just make those 40ft brighter-it will not make the light go 80ft

so they amplify the space they are in, but each bulb has a maximum reach, space them out and you will cover more area with same energy (cept where they cross beams), put them together and the light will be brighter in that smaller area

Everyone is saying the same basic thing, but arguing over slight semantics. Basically, the farther from the light, the less energy the plants receive, the higher lumens generally means you can basically keep your light at a farther distance to give them same energy (you really have to because of heat) again tho, lumens arent worth much to plants so it makes little difference.

I would much rather have my HID higher up covering all plants and use HO T-5's, CFL's and or LED on the sides to help cross light beams and make sure everything is getting ample light. a light meter is nice to have too-not too expensive, relatively speaking of course lol. camera shops have nice ones for cheap

Basically though, get these old ideas out of your head, I have had great results with LED's, but only as supplemental because of the narrowed spectrum-but combining them with HID is amazing, uses less energy and not as toxic to mother nature as CFL, and fills the gaps of most HID spectrum.

Personally my fave setup for an all in 1 tent (veg n flower if u need)if you can beat the heat, is 1-1000w Hortilux BLUE MH (want a 600w but not available n 400 is too weak for my area's) 3-HO T-5's along each side of tent (hang vertically on walls at lower nodes), and depending on the $$ some LED's from the top, prob i have is them shading the HID some, but i keep them in the corners mostly and they stay outta way since the HID usually has weakest energy in corners, 1 heavy exhaust w/ can fan, 2 wall mount fans and you can get an easy QP off a plant. my temp stays 60-75F (15degree drop at night)

http://www.eyehortilux.com/blue.html check this bulb out - not trying to plug it, but best spectrum i have seen on an HID and results are impressive

 

[Nubby Tubbs]

hes full of poopoo bigv. if you have 2 100 watt bulbs you have 200 watts of light. double the lumens. thats why its twice as bright. think about it.

 

[bigv1976]

Can someone link a youtube vid on the subject maybe? I have seen a test where the guy had a light meter and I think I remember that lumens did go up when bulbs where added but not by double. I wanna say that it worked like 1 5000 lumen bulb was 5000 lumens but 2 was like 7200.

 

[VividDane]

Ok so if lumens dont add up the all the people growing with 26 watt CFLs are only giving there plants however many lumens come from 1 bulb?

Correct, inorder to increase the PAR (where chlorophyll a & b is being stimulated) there has to be an increase in the intensity of the light, not the volume of it. A CFL emits more PAR per watt then a HPS does, but the most powerful CFL I've come upon is a 300 Watt 9U. The intensity of this CFL is claimed as an alternative to a 600 Watt HPS, but i wouldn't count on it. I might buy a quantum-meter that can directly measure the PAR-levels at any given point of a grow-room (or lamp) and compare this and other bulbs to a 600W HPS. I own quite a collection and I don't seem to be able to find other people who has done this, other then lamp/led-lamp producers, and their word just isn't good enough IMO, since they could easily give a fair reference or suggestion to these values in the product datasheet/description. Most lamp-producers doesn't give any other info then watts consumed and lumens emitted at the very outer tip of the bulb-glass.

SOURCE
Photosynthetically active radiation (PAR), measuring radiance in watts, is much better than photopic units (lumens or lux) or radiometric units (watts or watts/m^2). PAR is a mesaure of lamp output in the spectrum that is actually useful to the plants. However, this data is only available for a small number of lamp models. An additional limitation is that the PAR watt treats all wavelengths between 400 and 700nm equally, but all wavelengths within that range are not equially effective for plant growth. Despite these limitations, PAR efficacy (PAR watts emitted/watts consumed) is a decent indication of efficiency for horticultural lamps. PAR irradiance can be measured using a spectroradiometer (not cheap!).

 

[VividDane]

Can someone link a youtube vid on the subject maybe? I have seen a test where the guy had a light meter and I think I remember that lumens did go up when bulbs where added but not by double. I wanna say that it worked like 1 5000 lumen bulb was 5000 lumens but 2 was like 7200.

doesn't matter if the lumens goes up, this would only apply to office-lighting etc. _NOT_ grow-lighting. Lumens is a measure of light that stimulates our brain through our eyes. Plants needs a different kind of light emitted at a different wavelength in order for chlorophyll a & b to be stimulated into photosynthesis. Lumens is BS in growlighting.

 

[VividDane]

a CFL with low lumens level most often has a higher emission of PAR then a similar CFL of equal watts and higher lumens output. This is because most CFL's are produced and tuned for a higher lumens level. This is also the reason why expensive CFL-lamps for plant-growing tends to have a lower lumens-output then similar noname or cheaper types.

 

[marti221]

Hello.

From the info that I have gathered while researching light and how its used by plants I can say I do know a quite a bit. However I wouldnt dare call myself an expert.... Not yet at least. hehe. First, we are going to start off with the basics. I think we all know that light is needed throughout the entire lifespan of cannabis (at least I hope I think that most of us here are interested in getting the most massive, dense, stinky bud we can while trying to stay cost efficient. (I feel like not enough people take cost into effect when giving their responses and opinions, and seeing how this is pretty much the main reasons we are all asking these questions, you would think people would think before posting simple high priced solutions. " Do two or 3 $30, 150w hps lights accomplish as much as a 250w or 400w HPS (costing usually minimum $100-$150)? UUUUUUGGGG JUST GO BUY A 600W HPS $300.... <---- Not a helpful response, if i had money to drop on a nice new hps ballast, then I probably wouldnt be asking if $30 lights would work, Thank you haha).

Anyway... Most of us also can agree that the specific kinds of light (wavelengths in nanometers-nm and specific colors-red,blue,green..., color temperature in degrees Kelvin-K) needed at the different stages of development are also widely accepted. Knowing the wavelengths of light needed for both vegetation stage and flowering is one of the many keys to a successful grow. Cannabis like other plants uses primarily blue light (apprx 450nm, or 5500-6000k) with little red during vegetation, and red light (apprx 650nm, or 2200K) with little blue during the flowering stage. Now that we know the kinds of light needed, lets discuss the light sources that will create these ever so important wavelengths. First, lets discuss cfls, though they are sufficient and even preferred in many cases for veg, they are not optimal during the flowering stages due to the lack of "intensity." While I have always been told (and constantly see in posts) that more light equals bigger yeild and thicker, denser buds. This brings me to my main question... What is "more light"?

The general unit of measurement you are going to see advertised by light bulb companies are called Lumens. Lumens, in short, measure the amount of light seen by the human eye. As you can imagine, this isnt the best way, or even a good way to measure light for plants. Why you ask?...We "see" or use in the plants case, light differently than what the plant uses for photosynthesis. The human eye is much more sensitive to some colors of light (different colors are caused by different wavelengths of light, red= apprx 650 nm, blue=apprx 450nm), primarily yellow. Plants dont even use the green light viewed by us. This is how plants get there green color, because they are reflecting the unused green light . For example... We now know plants dont use green light, they use or absorb blue and red light predominantly. This means that any light source giving off green light, yellow light remember because the human eye is more sensitive to yellow light (though plants do absorb little yellow/orange light for photosynthesis) or any other color not being absorbed by the plant, is still represented in the "total lumen output" on the light package. So when a light bulb claims to have a certain amount of lumens, only a small percent is actually being used by the plant. This is also why you may see multiple cfl bulbs of the same wattage but with different Kelvin temperatures (another way of representing light, 2200k=red light for budding, 5500k=blue light for veg) with names like "soft while "or" cool blue,"have quite a big descrepancy in total lumens.

PAR is a much more effective way of measuring light because basically, (without all the scientific lingo) it measures the amount of light actually useful to the plant (as I said, red and blue light predominantly). As for " adding light," from what I have read you cannot technically add lumens or PAR (basically you cannot increase the intensity of the light by adding wattage). Which does make sense if you think about it. Two 250w hps lights will not be giving your plants twice the intensity, just twice the light. However the one thing that I havn't really seen people talk about is photons. Don't get me wrong, I am no scientist. I have taken a few chem, bio, cell bio courses for my major but i no way am I an expert. Anyway... photons. Photons are the individual "particles" of light that are given off by lamp or any other source of light. Plants use the light energy (photons) and convert it into chemical energy through chlorophyll via photosysthesis (Im sure we all remember this from elementary school).So this got me thinking... We do know that neither lumens or PAR can be "added" together to form higher intensity light. My theory is that plants even when flowering may not necessarily need this increased intensity, but just more photons. This is where I need to do some more research but my thoughts are that though PAR cannot be added, photons seem like they should. I dont see how adding 2 lights closely together wouldnt increase the amount of total photons absorbed and/or present. Like I said I am no expert. Increased intensity in light may increase the amount of photons in a given space leading to larger and denser buds, but I dont know. I havent really come across any posts explaining the million dollar question... WHY DOES INCREASE IN LIGHT INTENSITY LEAD TO LARGER DENSER BUDS???? or is it even the "Intensity" that causes this? or What technically is light intensity?