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Full Spectrum Lighting - Is it any better? 58

lennon asms: "Lighting in my apartment sucks. I am giving some thought to full-spectrum lighting fixtures, like the the Vita-lite. Some places say it's not any better than regular lighting, others say it's just great. What do you think?" I find the quality of lighting in my work environment to be very important. Would lights such as these be better than your standard soft-white or flourescent bulbs?
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Full Spectrum Lighting - Is it any better?

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  • by Anonymous Coward on Wednesday January 02, 2002 @02:11AM (#2772736)
    IT people don't need lights! we are trolls (like this post). Lighting like that will give us the same problem real sunlight does -- Turn us to stone!!!!
  • ...And that is you! It is fortunately not uncommon that different people have different preferences. That's why asking others will often result in different people giving you different answers.

    Whether you prefer "full spectrum lighting", "blacklight", normal lightbulbs, "warm" lightbulbs, darkness, daylight through the window, stroboscope, or any other form of lighting is up to you.

    If you think "full spectrum lighting" will make you happy, try it, and see what you think. End of story.

    • Agreed - you'll just have to try it. I recently replaced all my "normal" bulbs with GE "Reveal" bulbs. The great part? They're extremely cheap right now (I think I found them on sale for *less* than the price of normal bulbs). The bad? They (the cheap ones at least) don't put out as many lumens per watt as a normal bulb. It appears that the cheapo incandescent ones I got merely filter out most of the yellow, so therefore you get a more complete but also more dim light. They're not too much more dim - 15%-20% if I remember correctly.
  • Bounce the light (Score:3, Interesting)

    by Usquebaugh ( 230216 ) on Wednesday January 02, 2002 @02:36AM (#2772776)
    I really like soft diffused light, I have 40watt bulbs that I bounce off my walls and ceiling the reflected light is much softer.

    If you have to do a lot of paper reading then this is not the best solution but for staring at a TV or monitor it works well for me.

    Of course the other solution is not to do any work after dark!
  • Works for me (Score:4, Interesting)

    by maetenloch ( 181291 ) on Wednesday January 02, 2002 @02:39AM (#2772779)
    I put full spectrum bulbs in my office several months ago, and so far I've been very happy with them. I have a private office, but unfortunately without any windows so the only light sources are fluorescent lights. I got the full spectrum lights from Home Depot for only about $6 (GE I think). There are some other specialized manufacturers that charge $40+ for their bulbs, but as far as I can tell, they're essentially the same as the ones i got at Home Depot.

    The difference is quite amazing - I never realized how sickly yellow the old lights were. The new lights have much more blue in them, and really do seem more like natural sunlight. Now I feel like I have skylights in the ceiling.

    I can't tell if changing the lighting improved my performance, but it did make feel more comfortable and alert in my office. My co-workers like to keep their office dim except for their monitors - not me, I find that a dark room strains my eyes and makes me sleepy. I may be an exception since a lot of programmers like a dim room setup, and in our main office the engineering wing has no fluorescent lights on at all. Still I find that I do my best work in a naturally lighted environment. Without windows, full spectrums lights are as close as I can get.
    • Re:Works for me (Score:3, Interesting)

      by Judg3 ( 88435 )
      I believe he's talking about the GE Reveal [gereveal.com] bulbs. And I'd have to agree. A few months both bulbs in my office went out, so I ran down to the store and picked up a four pack of the 100 watt Reveal bulbs (only 2.99$). Brought em home, pulled one out - saw the weird pinkish coloring (could be pink, i dunno - im colorblind), decided to give em a try anway... And I was amazed.

      The colors now are crisp and clear, and the price is just pennies or so above the normal cost of a 4 pack of regular bulbs. I went out and switched most of my house over, and will never go back! I used to think the headaches I got from staring at my PC all day was eyestrain, after I put these bulbs in they went away.

      Amazing what a 30 cent change in lighting does, eh?
      • <kidding>
        Wait a minute - how can we take the advice on coloration of lighting from someone who's colorblind?
        </kidding>

        heh heh heh... Seriously, though, I agree that the GE Reveal bulbs make a world of difference. (For the record, the glass in the bulbs is a bluish-purple color ;)
      • Re:Works for me (Score:3, Informative)

        by maetenloch ( 181291 )
        Now that I'm back at my office, I checked and actually I'm using GE Chroma 50 (AKA GE Sunshine) bulbs (CRI 91, 5000 Deg.). You can get more information at the GE FAQ [gelighting.com]. Also there's a nice comparison of different light sources here [www.dph.nl].
      • Definitely amazed.

        I cross-stitch; lighting is extremely important - it lets you see your colors, how the floss lies, etc. Anyways, a friend of mine was looking at Ott-Lites, which are ~$40 full-spectrum compact flourescent bulbs.

        This seemed a little steep to me; so I picked up a package of the GE Reveal bulbs and changed my front room bulbs (where I do most of my stitching). Even at $2.50 a package, I won't go back. Simply amazing difference.

        -misao
    • Re:Works for me (Score:2, Interesting)

      by billn ( 5184 )
      As normally diurnal creatures, natural sunlight stimulates hormone releases that support wakefulness in humans. Adding full spectrum lighting likely trips the same response.
    • Re:Works for me (Score:2, Interesting)

      I've found that the intensity of the light is almost more important than the color ballance. Good color ballence is esential for some tasks, but most interior lighting is just way to dim. I'm a strong beliver in full spectrum lighting but it isn't everything. I light my appartment with number of full spectrum fluorescent lights and regular ones. Right now I have 4 tubes on. I can turn on as many as 12 at one time. They are all reflected off the ceiling and provide a very even light level all over my appartment.

      • Yes, brightness is important. There's few things that can drain my energy faster than a measly 60w ceiling bulb. But that many flourescentes would drive me crazy.


        I once tried an Ott light [ott-lite.com] (supposedly a full-spectrum flourescent). It's a great, *bright*, white light, and sure the contrast is amazing with it, but there's so much glare, I couldn't even read a book printed on white paper by it!


        For computer use specifically, playing with monitor colour and temperature is a must. Jacking up the reds works wonders for my eyes, especially in blue flourescent light. Oddly enough, I noticed almost no reflection when I made this change at work; with the default blue monitor setting, the monitor was almost unusable in the default position.

    • by coyote-san ( 38515 ) on Wednesday January 02, 2002 @10:58AM (#2773691)
      Hmm... on the one hand you have large rooms lit by the standard el cheapo fluorescent tubes. On the other hand you have a bunch of educated people prefering darkness to bad illumination.

      Think it's just a coincidence?

      Now toss in the fact that most monitor's (and all TVs) are "hot" - they're far more blue than they should be since it's a cheap way for the manufacturer to make them look "bright." (That's also why rooms with TVs look blue from outside.) Better monitors allow you to adjust the "color temperature", but most people don't know about this control or find a cooler temperature "dull."

      This means that people who work in front of a screen are getting hit with excess blue, and the overhead fluorescent lights also have excess blue.

      Still think it's just a coincidence?

      Personally, I wouldn't mind seeing OSHA mandates that overhead lights be full-spectrum and monitors be adjustable to the natural temperature (6500K?). It takes a few days to get used to it, but it's a lot more comfortable.
      • I come from a commercial printing background. In that industry lighting is a BIG DEAL

        Natural Sunlight on an average clear day is around 6500K. The industry standardized on 5000K based on some french research. It's been a while and I don't remember the details of the CIE study that produced the information. Mostly it was about the standard observer. Most of your calibrated light tables and viewing boxes are 5000K.

        We switched over to 5000K flourescent tubes in our office a few years ago to make it easier to judge color proofs and the difference was amazing. These tubes have illuminants that provide 91% of the full spectrum. They're about $5/per tube, but they last longer than your standard el-cheapo brand.

        If you are a light-sensitive person give these a try, you'll probably be pleasantly surprised and it may improve your mood, particularly during the winter.

        YMMV and unfortunately I don't remember the exact details of the bulbs. I believe they are functionally equivalent to the other full-spectrum bulbs available but we purchased them through our graphic arts supplier so I know they could be gotten cheaper elsewhere.

        I went back into programming and now all my illumination comes from halogen desk lamps.
      • This means that people who work in front of a screen are getting hit with excess blue, and the overhead fluorescent lights also have excess blue.

        You may be correct about the monitors, but fluorescent lighting is heavy in the yellow, since that's the part of the spectrum we see best. As a check, you can expose some "daylight" film in fluorescent lighting and note the yellow cast. Or ask a lighting specialist for the spectrum.
      • > Now toss in the fact that most monitor's (and all TVs) are "hot" - they're far more blue than they should be since it's a
        cheap way for the manufacturer to make them look "bright.


        OK, that's true. But as one who doesn't normally use lighting other than what's on the monitor, I find anything less than 9300K to look horribly yellowed-out and sickly.


        I, too, saw a pack GE Reveal bulbs on sale at my local hardware store. Unsure if compact fluorescents would fit in the fittings I had, I tried a pack of Reveals. Side-by-side with the regular incandescents, the difference is like night and day. For those of us that like high color temperatures (hey, for me, the light of the monitor is more "natural" than sunlight ;-), Reveals rock.

    • Without windows, full spectrums lights are as close as I can get.

      Humm, watch out here. Are you understating that better lighting applications exists under Windows ?

      I can hear the /. crowd hitting at your door from here...

      Olivier
  • Great, but.... (Score:3, Informative)

    by cpuwizard ( 171248 ) on Wednesday January 02, 2002 @03:43AM (#2772864)
    Having put them in my office a few years ago, I must say I love them. The only problem is that you must do it to EVERY room. Otherwise, other rooms become obviously yellow (or pink or green if you have fluorescent).
  • by Stillman ( 185591 ) on Wednesday January 02, 2002 @04:57AM (#2772963) Homepage
    We had FS lighting installed in our offices at the beginning of erm...last year.

    I could not go back. I used to get headaches on a fairly regular basis that I just put down to tiredness/stress/whatever. They went away after about two weeks with the new lights.

    I find I can work longer hours with no problems - except an annoyed wife!

    I also find I can concentrate a lot better.

    My cow-orkers have all noticed similar benefits - we were discussing it at our christmas function.

    So, yeah, on the whole...get those bad boys! :)
  • Borders Book Store (Score:1, Interesting)

    by Perdo ( 151843 )
    They have natural full spectrum lighting. My red headed girlfriend worked there. She was always very carefull in the sun. She hould come home burnt every day. We went on vacation and she lost her burn. Back to work and she got burnt again. She mentioned it to her boss and was "let go" for "administrative reasons".
    • by Anonymous Coward
      That sucks. You should have reported this to OSHA. That way, when she was "let go" you could try to go after them. Boarders Book Store is a very horrible place. There was an article a few months ago on /. about how they were going to place face-recognition software in their stores to compare with their own list of shoplifters. If you do some searching in google, you will find out that they are VERY VERY anti-union. So far as to close up shop once when the employees were going to join a union. I boycott the store, and I now have all of my friends and family boycotting them too. I know thats not a big acheivment, but its a start :)
      • Unfortunately, the other major chain (Barnes & Nobel) has decided that constant mass mailings aren't really spamming, not even after I have repeatedly asked them to stop and threatened to boycott them if they don't, since I bought a book from them online once.

        So no more Barnes & Nobel. If I'm in the area I'll hit the Tattered Cover (which is a far better bookstore than either of the other two), but it's too inconvenient for routine use.

        So do I choose the chain that sh*ts on its employees, or sh*ts on its customers? What a choice....
      • by Anonymous Coward
        Funny, I shop them *because* they stand up to the union. C'mon, Borders isn't a career. There's no need for a union. Quit. Work at McDonald's and double your pay. I can't imagine them staying in business if they were forced to give in to the demands of a union. The margins are too small. Just witness the price differential between US cars (unionized labor) and Japanese cars built in the US (nonunion).
      • I prefer Borders to B&N but still dislike both of them since they're corporate monoliths. (btw I prefer Borders since they have no problem with their cafe section mingling with the perusing section.) But now that you have told me they are anti-union then that is another plus for Borders!

        t.

    • Sunburn is actually a radiation burn from several types of powerful radiation from the Sun. The largest contributor being photons in the UV light range, not in the visible spectrum. Full Spectrum lighting is simply running hotter, with a modified phosphor to achieve a more complete light spectrum. Yes, they usually produce more UVA and UVB than a standard bulb, but UV makes up a tiny % of total emissions(~1%), the energy levels produced don't cause them to travel far(24"), and the production drops off 3x faster than than the visible spectrum drops off over the life of the lamp. So, unless your girlfriend is so sensitive that 5 minutes uncovered in direct sunlight causes a bad burn, she might have some other condition she is reacting to. Check out this site on Full Spectrum lighting with pet birds: http://www.users.mis.net/~pthrush/lighting/spectru m.html
  • I find full spectrum light incredibly harsh and cold. I did a project years ago in a lab that was lit by full spectrum lights and it made my head hurt. Maybe things have improved in the last 10 year, I don't know.

    The best lighting is indirect incandescent, or from things like candles and oil lamps (although that's too dim to read by). Indirect Halogen (OK, so Halogen is a kind of incandescent..) lighting is OK too. Fluorescent lighting is evil and must be stopped, but every office in the universe uses it for cost reasons.

    I notice that there's a new and extra-bright kind of headlight in production with a slight bluish tint. That's pretty unpleasant too - I think they are metal halide based, but no-ones trying to light a room with them yet as far as I know.

    Old yellow sodium lighting is disgusting too unless you go for that deserted carpark feel.

    I was walking through Hyde park last night an noticing how nice gaslight is....
  • by stinkydog ( 191778 ) <.sd. .at. .strangedog.net.> on Wednesday January 02, 2002 @10:44AM (#2773637) Homepage
    The quality of flouresenct light is affected by many factors:

    Color Temperature
    Bulb Quality (you get whast you pay for)
    Power and Ballast quality (Flicker)

    For some other thoughts check this out [inlandreef.com]. It is about lighting fish tanks and not cubes but it is still applicable. I supplement my flouresents with an incandescent bulb for better quality of light. More information on lighting theory is available here [gamonline.com].

    Try some of this [gamonline.com] if you want a different color.
  • by gully42 ( 212724 )
    You will find that full spectum does provide a nice psychologial effect, especially if you are in and out of the sun alot. your eyes gradually adapt to lousy light (like older fluorescents), but the difference can be rather striking. Nothing beats real sunlight though. Full spectrum lighting is essential in locations where you must carry out color-sensitive tasks (retail, hospitals, electronics assembly). But it is also nice in home environments, good for skin tones and fabrics. I suggest newer (Tri-phosphor) fluoresecnt lights, they provide a very broad spectrum and efficient output.

    • Its also great for fish tanks and raising aquarium plants. I'd imagine that it would be good for indoor plants as well.

      I'd recommend multiple bulbs of different spectrums or a full spectrum bulb. Vita lite makes florescent bulbs and you can get red, blue and green colors I believe as well as white. They also have full spectrum bulbs. At least this is what I know they make for the aquariums and there is no reason that you cannot use these bulbs in a home or office. The drawback is that they are florescent, which means that they flicker at about 60hz or the cycle of the power coming out of your sockets.

  • light mood (Score:1, Informative)

    by Anonymous Coward
    The guy who wrote the book (Winter Blues) on
    how light affects mood is Dr. Norman Rosenthal
    (http://www.normanrosenthal.com)
  • I believe there was a study in either JAMA or NEJM regarding whether it was the spectrum or the intensity of the light which decreased the incidence of Seasonal Affective Disorder. I think the study showed an improvement did occur with both, but better results with the increase brightness. I'd personally get a corner office in a sunny local.
  • Full Spectrum or ? (Score:2, Informative)

    by gordguide ( 307383 )
    First of all, I want to go on record as saying I have tested/tried FS lighting and I am supportive. For me, it worked very well.

    Fleuroescent lights, by their nature, are mixtures of gases which approximate "real" light. Generally you could think of it as similar to theatre light; add the 3 colors and you get white.
    However, FL gases are not a smooth dim-to-bright-to-dim spectrum type of light. There are always areas of the spectrum that are missing, and it is the careful (or haphazard) choice of gas that determines how close it can get to white light.
    Incandescents are continuous spectrum, with typically blue missing (hence the yellow cast in photos). But, and this is a big but; they are continuous from the "first" color to the last color they can display. FL lights will have gaps (some of the colors of the rainbow are missing entirely).
    Thus, FL "full spectrum" lights have more attention paid to haveing all colors represented, but to do it like sunlight, candlelight or incandescent light is pretty much impossible. There will still be areas of the visible spectrum with little or no output. That's why they cost more than "regular" FL's (some of the gases cost more) but they still may be unsatisfactory to sensitive individuals or for critical color matching.

    Incandescent Full Spectrum are available; the drawback is cost and overall life. In other words, you probably won't see them in the IT department of MegaCorp. FL Full Spectrum are then still a compromise; it is possible for some individuals to get headaches from them (as they can from all FL lighting).

    Having said all that, Full Spectrum are usually better than regular "el cheapo" FLs if that't the kind of light you're stuck with. Just as with regular FLs, brand and product differences exist, so some experimentation may be necessary.
    • by dhartshorn ( 456906 ) on Thursday January 03, 2002 @04:07AM (#2777817)
      when you wrote that? Have you ever looked at a spectral analysis of a fluorescent light? The ones I'm looking at (Illuminating Engineering Society Lighting handbook, Reference Volume) show a continuous distribution with four spikes that are present in all bulbs classified (Cool White, Warm White, White, Deluxe Cool White, Deluxe Warm White, and Daylight).

      Your theory of gas mixtures affecting color is also incorrect. Fluorescent lights are the product of an electrical discharge in a low pressure mercury vapor. Some trace gases are added to improve startup, but not color. Color is determined by the phosphor coating on the glass, in exactly the same manner color is determined in CRTs. Change phospors, change colors.

      Observing the spectra of the different classes of fluorescent bulbs shows that Cool White (most typical) differs from Daylight by a reduction in the red (slight) and yellow (significant)and an increase in the green (slight) and blue (significant). Cool White has a yellow component peak that is approximately double the value of the peak that straddles blue and green. In the Daylight bulb, the peaks are relatively the same. The two of the four spikes (yellow, green, blue, and indigo) are also affected, with yellow reduced and indigo boosted.

      Incandescent (tungsten filament) lamps are stronger radiators in red than blue, following a somewhat straight line that gives us a red luminace that is approximately 4 to 5 times greater than blue. Yellow comes in at about 3x blue.

      Sunlight has a strong peak in the blue-green and decays to about half power in the red. Continuous, but not uniform. And it clearly demonstrates why Daylight bulbs boost the blue component (while still leaving at least 1.5X the "natural" yellow component).

      (This clearly shows that six pictures and some graphs are worth a couple hundred words.)
      • "... Full-Spectrum Fluorescent Lamps in Context
        There are two broad classes of electric light sources available for interior lighting; incandescent light sources and discharge light sources. Incandescent light sources produce light by heating a filament, the spectrum of the light being determined by the temperature of the filament.
        Discharge light sources produce light by passing an electric current through an ionized gas; the spectrum of the light being determined by the gas used, the gas pressure, the other elements in the discharge and the presence or absence of a phosphor coating. Full-spectrum fluorescent lamps are low pressure, mercury discharge lamps with a phosphor coating. The discharge in the mercury atmosphere produces mainly ultra-violet radiation. This ultra-violet radiation is largely absorbed by the phosphor coating lining the walls of the discharge tube and reradiated as light. Incandescent lamps have a continuous spectrum in the visible region, dominated by the long wavelengths (see Figure 1).
        Discharge lamps typically have a spectrum consisting of strong single wavelengths amongst a continuous background ... "

        From:
        Is Full-Spectrum Lighting Special?
        Peter R. Boyce, Ph.D.
        Lighting Research Center
        Rensselaer Polytechnic Institute
        Troy, NY 12180-3590 U.S.A.

        Okay, I stand corrected. After all, when you look at graphs of FL lighting, there is a "continuous spectrum" of light, typically 100 times less bright than the spikes. So, technically, you're right. In layman's terms, I stand by my assertation that the light emitted is dominated by a few bands of color separated by nearly no light output in other colors.
        The type of gas used can and does affect the light specrum. Phosphor coatings are not present on all types of FL tubes; it depends (again) on the desired lighing qualities, including spectrum.

        100W Incandescent: less than 10 mw/nm at approx 450nm, rising steadily to 50mw/nm at 800nm.

        65W FL: Less than 10mw/nm at: 300-400 nm but with a narrow spike of 35mw/nm at about 370nm; approx 25mw/nm at 400-500 nm but with narrow spikes of 75 and 200 at approx 410 and 430nm; medium width spike at approx 570nm of between 50 and 150 mw/mn.

        90 W Low Pressure Sodium (isn't that a different gas?): virtually no output (no measurable output on the graph, could be some at 10mw/nm or less) except for a 3300mw/nm spike at about 590 nm.

        400W Metal Halide Mercury: Spikes of 1000 mw/nm at approx 300, 350 and 400nm; spikes of 1500 mw/nm at approx 550 + 580; one spike at about 620nm of about 800mw/nm. Output at all other wavelengths less than 30mw/nm, some not showing on the graph at all (could be zero?).

        Now, a graph is a funny thing to base your info on (easily fudged and "prettied up"); these are from a submitted paper. However, feel free to read the whole thing (and more) at:
        http://www.nrc.ca/irc/fulltext/ir659/contents.ht ml

        The quoted paper is available PDF on that page, as are others.
        • Phosphors are present on all fluorescent tubes. Low pressure mercury vapor emits in the UV. The only visible light emitted from a fluorescent tube is from the phosphor coating. The spectrum of a fluorescent light is continuous and not "typically" 1/100 the peak values.

          Your description of an incandescent is correct, matches mine, and has never been at issue. The only thing I disagreed with in your previous comment is the premise that continuous spectrum sources are better than fluorescent. Incandescent tungsten lighting doesn't match solar spectra any better than the worst fluorescent.

          Your fluorescent description is approximately correct, but it's worth noting that we don't see wavelengths less than 370nm. Starting at 400nm, your description accounts for an 8X difference in intensity, not the 100X you claimed. Which of your answers is correct? The IES chart shows the base level as greater, and is the standard of the lighting industry. I'll stick with that data.

          Low pressure sodium is _not fluorescent_ and would be encountered indoors only when hell freezes (or some such approximation of never). You've likely seen it as the orange lighting in a parking lot. Its companion, High Pressure Sodium lighting, appears amber and is also normally used outdoors. Occasionally, HPS lamps are used indoors with Metal Halide lamps to produce an economical and relatively color accurate light.

          Metal halide is _not fluorescent_ and is commonly used in industrial settings indoors, and as the most accurate color source for outdoor area lighting.
          • "... The only thing I disagreed with in your previous comment is the premise that continuous spectrum sources are better than fluorescent. Incandescent tungsten lighting doesn't match solar spectra any better than the worst fluorescent. ..."

            That statement is simply laughable. I hope you don't read by the light of the "worst fluorescent".
            • Wow, pick one unimportant nugget and run with it. Can I presume that you now understand the errors in your other comments?

              I do read by the "worst" fluorescent and have no difficulty doing so. Black on white text is easily handled by a cool white bulb. If it weren't, we wouldn't be using them nearly universally in professional and commercial space. Or will you now point to some vast right wing conspiracy to deprive us of a proper environment?

              With regard to my "laughable" statement, feel free to compare the spectra and show me up. Given the accuracy of your previous statements, I suppose I can safely let this thread die.

              Or not. Read your own source and note what a full spectrum fluorescent adds that cool white and others lack. Blue. What else lacks blue? Your continuous spectrum darling, the tungsten incandescent.

              Look at the roll off of the longer wavelengths in the solar spectrum and the cool white and contrast that with the nearly linear increase of the incandescent.

              You discuss our attempts to create "real light", which I take to be sunlight. If that's the case, cool white beats tungsten incandescent.
  • I'm working from home these days, and noticed that the regular incandescent bulbs weren't making feel too productive. I switched over to the flourescent and it's so much more of an improvement. As for the benefits of a VItalite, you may not get them because you would have to be within the effective range of the bulb, which is typically 12-18 inches, so go outside once in awhile.

    Unfortunately I had to give the light back to my turtles. ;=-)
  • I replaced my overhead fluorescents with full spectrum tubes bought at Home Depot, makes a big difference in cube land!

    GE also sells Reveal [gereveal.com] incadescent bulbs that are cheaper than compact fluorescents and are great for reading lamps.

    The next step is "tune-able" light bulbs Solux Lightbulbs [wiko.com]why should your stereo have an equalizer, but not your lightbulbs?
  • "fluorescent" is spelt thus. It's not that hard.

    Thank you for your attention.
  • I can say that full spectrum bulbs give your pot plants the best yield over ordinary flourescent bulbs.

    Effect shouldn't be that different on humans.

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