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Full Spectrum Lighting - Is it any better?

Posted by Cliff on from the as-long-as-it-works-with-a-prism dept.

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?

5 of 58 comments (clear)

  1. Great, but.... by cpuwizard · · Score: 3, Informative

    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).

  2. That may not be a coincidence.... by coyote-san · · Score: 5, Informative

    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.

    --
    For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
    1. Re:That may not be a coincidence.... by RobbieW · · Score: 3, Informative

      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.

  3. Re:Works for me by maetenloch · · Score: 3, Informative

    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. Also there's a nice comparison of different light sources here.

  4. What were you smoking? by dhartshorn · · Score: 4, Informative

    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.)