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What Font Color Is Best For Eyes? 702

juraj writes "What font color and what background is best for the eyes, when you work for a long time? I have found various contradictory recommendations and I wonder if you know about any medical studies on this topic."
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What Font Color Is Best For Eyes?

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  • by JWSmythe ( 446288 ) * <jwsmytheNO@SPAMjwsmythe.com> on Tuesday April 08, 2008 @10:34PM (#23008062) Homepage Journal
    Yellow on red [jwsmythe.com] seems like a very popular high contrast color combination for several years.
    • by CastrTroy ( 595695 ) on Tuesday April 08, 2008 @10:38PM (#23008106) Homepage
      I remember that from Windows 3.1. I think they called it hotdog stand.
    • by JWSmythe ( 446288 ) * <jwsmytheNO@SPAMjwsmythe.com> on Tuesday April 08, 2008 @10:44PM (#23008168) Homepage Journal

      Ok, that post was for fun. :)

      For my shells, that I stare at for hours, I use:

      green on black

      yellow on black

      white on black

      It's usually green on black. I use yellow on black for special shells (like when I'm using a lot of shells with cssh). Putty defaults to white on black, so when I'm stuck in Windows land, that's it.

      Any shells that default to black on white, I switch immediately. It's not so bad in a web browser, but there's something about a shell and typing in it that hurts my eyes. It could be that I'm concentrating that much more on the text on the screen, since it's usually fast data. Like, tail logs on a busy server, or run top with a refresh of 1 or 0. I catch details that other people don't even notice on their machines.

      • by scum-e-bag ( 211846 ) on Tuesday April 08, 2008 @11:26PM (#23008546) Homepage Journal

        It's usually green on black.

        Any shells that default to black on white, I switch immediately. It's not so bad in a web browser, but there's something about a shell and typing in it that hurts my eyes.
        Same here. I think it may have something to do with green lying in the middle of the visible spectrum. Similar concept as police/emergency lights being red/blue at opposing ends of the visible spectrum allowing for maximum visibility under maximum conditions.
        • by arth1 ( 260657 ) on Tuesday April 08, 2008 @11:51PM (#23008714) Homepage Journal
          Our eyes don't work like that -- they don't scan the visible spectrum from low to high, and see blue as the opposite end of red. Instead, we have receptors for certain colours, and base our colour perception on how much each of those get triggered. This is why colour blindness hits red/green or yellow/blue, despite those colours not being adjacent on the spectrum.

          Our eyes can differentiate shades and hues of green better than any other colours -- this is an inherited survival trait from when it was important to see predators and distinguish ripe from almost-ripe. Blue, on the other hand, wasn't as important to survival, so we can't tell too many shades of blue apart, nor very far towards ultraviolet. We perceive indigo (the traditional indigo, not the "purple" that's called indigo these days) as a dark colour, for example, because it's at the edge of what we can see.
          • by enoz ( 1181117 ) on Tuesday April 08, 2008 @11:56PM (#23008734)

            this is an inherited survival trait from when it was important to see predators and distinguish ripe from almost-ripe.
            I know there is probably a very good reason for that, for example being able to distinguish a camouflaged predator in dense jungle.... but I just can't get the image of big green lizard predators out of my head.
          • Re: (Score:3, Interesting)

            by ganelo ( 1269780 )
            I was under the impression that there were two leading models of human color vision: opponent-process and trichromatic. Trichromatic stipulates that the there are three types of cones that register light at three different wavelengths corresponding to red, green, and blue. This theory is pretty well-supported in general. However, this theory does nothing to predict or explain afterimages (i.e. seeing a blob of purple in the shape of a bright [yellow] light after looking away from it, or seeing blue when
            • by Malekin ( 1079147 ) on Wednesday April 09, 2008 @03:02AM (#23009936)
              The three types of cones are generally referred to as L, M and S cones (for long, medium and short wavelength peak sensitivity) The S cones peak at what we call blue (~435nm), the M at green (~534nm) but the L do not peak at red. The L cones have a peak sensitivity at about yellow-green (~564nm).

              We use red because red is way out the end of the visible spectrum and red light excites the L cones but not the M cones. If we were to use yellow-green we'd be exciting the M cones too much. The average person has about twice as many M cones than L or S cones, (we're very sensitive to green light) so yellow-green ends up exciting the M cones more than the L cones. By adjusting the amount of red (L cone excitation), green (M cone excitation) and blue (S cone excitation) we can replicate in the eye the cone response any visible colour would generate.

              The human vision system is not like a camera - the cone response is only one part of a long and complex chain. Afterimages are somewhat a function of photo-pigment bleaching and later stages of visual processing in the nervous system and brain.

              Cone response references:
              Stockman, A. & Sharpe, L., "The spectral sensitivities of the middle- and long-wavelength-sensitive cone derived from measurements in observers of known genotype'', Vision Research, Volume 40, Issue 13, Pages 1711-1737, 16 June 2000

              http://cvision.ucsd.edu/cones.htm [ucsd.edu]
            • Re: (Score:3, Informative)

              by AaronW ( 33736 )
              Wikipedia [wikipedia.org] has a good article describing this and the fact that our eyes are actually sensitive to blue, green and greenish/yellow. Red is what you see when the greenish yellow receptor is active but not the green, hence why we aren't all that sensitive to red light but very sensitive to yellow and green. Similarly if only the blue receptor is active you see a deep violet like what you get from a black light.

              As far as monitors go, it's often easier on the eyes if you lower the color temperature to 6500K.
          • by dgatwood ( 11270 ) on Wednesday April 09, 2008 @01:17AM (#23009374) Homepage Journal

            Our eyes don't work like that -- they don't scan the visible spectrum from low to high, and see blue as the opposite end of red. Instead, we have receptors for certain colours, and base our colour perception on how much each of those get triggered. This is why colour blindness hits red/green or yellow/blue, despite those colours not being adjacent on the spectrum.

            Yeah. That's also why unless you are colorblind, light yellow on a very dark blue will probably be about as readable as it gets because it has both luma contrast (difference in rod response) and chroma contrast (the yellow hits the red and green cones hard with just a little on the blue cones, the blue hits the blue cones and barely registers on the others). Even if you're colorblind, the huge difference in contrast should be sufficient to make it reasonably readable.

            The absolute worst, IMHO, is white on medium green... you know... road sign colors. Unreadable until you get right up to the things, by which time you end up cutting off the guy in the next lane to slam your car into the exit lane that should have been marked 200 feet earlier.... :-D

            • by Sandbags ( 964742 ) on Wednesday April 09, 2008 @09:22AM (#23011870) Journal
              A lot of cities have started installing new road signs that are white on blue, or even a faint yellow on blue. They're also making the text paint reflective, but not the background blue. Unfortunately, the cost of replacing all the road signs is prohibitively expensive, but at least new ones going up are a lot easier to read.

              I still wish someone would start requiring road signs to be sized appropriately for the speed of the roads. Speed limit signs are required to be larger in places where drivers go faster to give them additional distance (time) to be able to recognize the sign. Road signes need to do the same.

              Additionally, we should have cross street hanging signs (the big ones hanging from traffic light wires) on every block in cities... Here in my city, it's hit and miss, some streets have them, others don't. if I'm in the left lane, there's little hope I can read a street sign, even when parked at a light. It's simply too far away to read 3" tall letters... especially on green backing.
          • by Solandri ( 704621 ) on Wednesday April 09, 2008 @02:59AM (#23009908)

            Our eyes can differentiate shades and hues of green better than any other colours -- this is an inherited survival trait from when it was important to see predators and distinguish ripe from almost-ripe
            Not quite. Our eyes are most sensitive to green simply because that's the frequency at which sunlight is strongest [nature.com]. Red is next most sensitive, while blue is least sensitive [gamesx.com]. Which matches exactly with the spectra strength of sunlight. (Actually, the red cones are most sensitive around yellow/orange [webexhibits.org], and the color red is extrapolated by your brain from a lack of response from the rods and green cones.)
          • by SnowZero ( 92219 ) on Wednesday April 09, 2008 @04:27AM (#23010320)
            Argh please don't mod this up so high, as people are going to read this and believe it without further research. I'm sure you meant well arth1, but it seems you weren't taught the whole story.

            Our eyes don't work like that -- they don't scan the visible spectrum from low to high, and see blue as the opposite end of red. Instead, we have receptors for certain colours, and base our colour perception on how much each of those get triggered. This is why colour blindness hits red/green or yellow/blue, despite those colours not being adjacent on the spectrum.

            Yes, we have different color sensors, but this is beside the GP's point. The green response curve overlaps significantly with red and blue. See the spectral response here [ed.ac.uk]. Red/Blue flashing lights will cause a significant color contrast as they alternately hit one type of cone and then the other. Even though the response to blue is low, it is still an effective color to use because the human eye's response is logarithmic wrt to brightness (i.e. take the graph I linked above and take the log the y dimension). Even that's a simplification when you add rods to the mix, but that's a subject for another post or later research.

            Our eyes can differentiate shades and hues of green better than any other colours -- this is an inherited survival trait from when it was important to see predators and distinguish ripe from almost-ripe. Blue, on the other hand, wasn't as important to survival, so we can't tell too many shades of blue apart, nor very far towards ultraviolet.

            This is wrong. We can identify more hues of blue than any other color, followed by red, while the intermediate hue discrimination can be quite low. Green sucks because that cone's frequency response is highly correlated with parts of the other two, and thus it forms somewhat of a degenerate basis for describing a hue with the 3 weights. Google "Hue-discrimination curve" for more info.

            The evolutionary argument for this has *no* good evidence supporting it, but has become a very vibrant meme (I won't call it a legend, since it is an unproven theory). Green is bright for a variety of potential reasons: (1) It's one of the easier pigments for synthesize biologically, (2) There's a lot of green light coming from the sun, (3) It's a good baseline from which to differentiate other colors (there's a lot of green in our environment), and (4) yeah maybe it could have to do with rotten/ripe fruit. I'd bank on the first two though, especially noting that our hue sensitivity in the green range sucks. Predators are best to detect via motion (primarily rods), and by non-green cones (predators are camouflaged best against rods, i.e. non color vision, i.e. luminance, which overlaps most with green). You can of course believe whatever theory you want, but please don't start speaking about one as being authoritatively true; I know some evolutionary biologists like to extrapolate really far from the evidence, but it always hurts when they are wrong on some theory that gets discounted, since it gives creationists a hammer to bludgeon all of biology and science with. Please don't give them that ammo, and label speculation as speculation until there's real concrete evidence to show. For evolution of these traits, that means sticking mostly to the "what" and "how", and not claiming "why" except in the most general and statistically supportable terms.

            We perceive indigo (the traditional indigo, not the "purple" that's called indigo these days) as a dark colour, for example, because it's at the edge of what we can see.

            It's not just that its near the edge, it's more complicated with several factors: (1) The blue cones are not that sensitive, (2) there is no additive luminance response due to the other cones frequency response falling off completely at violet, and (3) the rods don't even respond to it very well (last point only really matters for

          • by nahdude812 ( 88157 ) * on Wednesday April 09, 2008 @07:30AM (#23011032) Homepage
            Red, being the longest wavelength of visible light (that lines up with a color receptor), carries farther especially in foggy, snowy, rainy, or other inclement conditions. This is why stop lights, stop signs, and tail lights are all red.

            Blue, being the shortest wavelength of visible light (that lines up with a color receptor), is seen more vividly and in greater detail than other colors. "Ultra white" paper is actually tinted blue because of this, and many whitening laundry soaps are reactive on ultraviolet (which tickles the blue receptors without being visibly blue).

            If you use a color calibration sensor, such as professional printers use, you will find that paper which is truly white in the scientific sense (equal strength responsiveness across the spectrum) seems kind of yellowish and bland compared to this ultra white stuff with it's big blue and ultraviolet spike.

            I think this is why police lights are red and blue, red to carry in inclement conditions, blue to get your attention.
      • by SoupIsGood Food ( 1179 ) on Wednesday April 09, 2008 @12:34AM (#23009010)
        Green on black terminal windows are the way they are for the same reason old oscilloscopes and radar displays were green on black - it's more cost effective to make a cathode ray tube that glows green. For a long damn time, all terminals came green-on-black, simply because that was the cheapest way to pair a CRT with a keyboard, and hardware terminals were what they used back before PC's were popular. Or invented.

        The result of this was horrific eyestrain. Yes, some people can handle bright colored text on a black background. Most get eyestrain or worse, migraines. This is especially so if you switch from green-on-black to black-on-white (like a printed page).

        Typists and transcriptionists and grad students and pretty much anyone who needed to refer to a printed reference hated it. In the early '80s, color monitors were pretty much crap for text (too fuzzy, not enough resolution) so there was a boom in the production of "amber" monitors. These used monochrome CRTs that phosphoresced a muted yellow-orange. This wasn't quite as jarring to the eyes.

        Then someone came up with paper-white monochrome CRT's, and that was pretty much all she wrote for greenscreens.

        Geeks keep it alive, because of nostalgia and tradition. It's looks high-tech and cool, because there was a time when it was high-tech and cool - and because there is an association with Unix, and by extension, Linux. What's more Unix than a DEC vt100 terminal hooked up to a PDP-11? Nothing. That's about as close to the metal as you can get without a soldering iron.

        But, please, for the sake of your eyes and the eyes of others, don't pretend there is any inherent advantage to green-on-black for the vast majority of users.
        • Re: (Score:3, Interesting)

          by SharpFang ( 651121 )
          Double bullshit.

          First, what is more tiring, some glow, when most of the retina remains inactive picking 'dark', or a full blast from a CRT tube against your eyes?
          There are these who prefer bright background with dark letters over the opposite, but I assure you you'll find few of these amongst CRT screen users, and the choice of white on black for office applications was to make it all resemble paper, the old known metaphor for 'surface for writing'. Not because it's easier on eyes.

          Then - did you ev
        • Re: (Score:3, Interesting)

          by antek9 ( 305362 )

          The result of this was horrific eyestrain. Yes, some people can handle bright colored text on a black background. Most get eyestrain or worse, migraines. This is especially so if you switch from green-on-black to black-on-white (like a printed page).

          And it never occurred to you that this might be the fault of the colour scheme these people were switching to? I always have to turn down my brightness and contrast settings as low as possible to be even able to read Slashdot for more than a few minutes.

          But sur

        • Re: (Score:3, Interesting)

          by oPless ( 63249 )
          Honestly, what a load of hogwash.

          Green-on-black is perhaps the nicest thing to my eyes ever, though I am partial to Amber-on-black.

          White on black hurts after a while ... Black on White hurts more - I have a *MUCH* lower tolerance working with an IDE with a white paper colour than a black one. Of course, being a proper programmer, I use vi from a shell :)

          Yes I actually used serial terminals for years, usually in the higher column mode - just because I could read more :)

          I kinda miss hacking on the old CP/M bo
      • by Moraelin ( 679338 ) on Wednesday April 09, 2008 @05:47AM (#23010638) Journal
        ... if black on white hurts your eyes, there's probably something else wrong there too. Not saying that black on white is optimal anyway, but it shouldn't be enough by itself to give you a headache or tire your eyes.

        It generally boils down to: IMHO most people I've seen using computers are doing it wrong for their eyes.

        For starters make sure you use a large enough, and clear enough, font so you don't have to squint. If you absolutely need 80 lines on the screen when editing sources, that's usually your clue that there's something wrong with your programming style (and I suspect for some people the short term memory too.) You shouldn't have methods that run over that many lines, unless they're truly trivial stuff. (Like, say, a long switch statement where each line does no more than delegate to a method of its own. Arguably there are better ways there too, but I don't find it to be the end of the world either.)

        IDE's also offer a lot of tools to find the method you need, when you need it, and/or collaps/expand blocks so the don't take up screen estate when you don't need them. There's also stuff like showing you the parameters anyway, so you don't have to have a second window in which you look for the parameters to that method. And really lots of other stuff. Use those instead of cramming the absolute maximum lines of text on the screen.

        When I see a couple of co-workers squinting at their 6 point Illegible Roman font in VI and doing greps manually in another illegible tiled window, heh, I'm just itching to tell them to move out of the stone age already. We even discovered this funky thing called the "wheel" in the meantime, ya know?

        Clean your monitor regularly, especially if it's a CRT. CRT's have thick glass, and your eyes end up focusing back and forth between the dirt on the front side of it, and the letters on the back side of it. But it's distracting and tiresome on TFTs too. And if you need to squint because you're at the point of "is that a 'm' or a 'rn'? Or is it 'rh' behind that speck?" it's long overdue for a cleaning.

        Do turn your contrast up, but turn your brightness down to a comfortable level. The monitor is not supposed to be an AA searchlight. Staring into very bright stuff, especially in a dark room, _is_ tiresome. Here especially the TFT's are the biggest offenders. The manufacturers got stuck on bragging about the brightness of their monitors, as if that's something good, and pre-set them to insanely bright levels. Turn that down to where you can live with the white for hours.

        And it will be even more important when you have to focus on stuff that's the other way around: white on black. (Some websites love that scheme, for example.) On an ultra-bright monitors that will mean focusing on a mostly black screen, so your pupils are wide open, but some pieces of retina are getting to see some really bright letters. It's a recipe for a headache.

        As a side-note, I'm genuinely surprised at how many people do the exact opposite. I've seen too many monitors which are turned to abysmal contrast, and as bright as halogen headlights. I mean, WTF? Some things are barely legible in that configuration.

        Ok, so maybe it's good for PC games, where the average dev seems to think that every fucking thing must happen in nearly complete darkness. 'Cause, you know, we have 32 bit colours so we can display all the gamut of "black", "really dark", "dark grey", "room with a broken lightbulb" and "grey stone on a moonless night". But the brightness settings where you see in near dark in games, suck for work or even reading in a browser. If you use the same monitor for games, consider turning up the brightness or gamma up in those, instead of turning the monitor's brightness all the way to the right.

        If you're stuck with a CRT, make sure it's a good one and properly tuned. Staring into an unfocused image, especially with small unfocused fonts, is a recipe for a headache.

        Again, for CRT users, just because everything idiotically defaults to 60 Hz, is no
    • by RuBLed ( 995686 ) on Tuesday April 08, 2008 @10:49PM (#23008212)
      I'm using Zenburn-like themes for quite sometime now and I find it pleasant to look at. (on the screen and not on paper, I just apply another theme if I want to print preview it)
      http://slinky.imukuppi.org/zenburn/ [imukuppi.org]
      http://en.wikipedia.org/wiki/Zenburn [wikipedia.org]
  • by GMThomas ( 1115405 ) on Tuesday April 08, 2008 @10:34PM (#23008064) Homepage
    Background :#FFFFFF Text: #FFFF00
  • by NuclearKangaroo ( 768480 ) on Tuesday April 08, 2008 @10:35PM (#23008074)
    I've been saying this for years, but no-one's paying attention, apparently...
  • Colour? (Score:5, Insightful)

    by Anonymous Coward on Tuesday April 08, 2008 @10:36PM (#23008076)

    When you work with computers for long periods of time, the colour of the font is nothing compared with taking regular breaks. Look out the window. Go for a walk. Make some tea. Bump up the font size. Get a bigger monitor and put it further away.

    You are focusing on a tiny, tiny, tiny piece of the problem. There are almost certainly a ton of ways in which you could reduce eyestrain by gigantic amounts in comparison without bothering with something as trivial as font colour.

    • The parent is correct. Calibration of a monitor can help nicely too as described in this post: http://ask.slashdot.org/comments.pl?sid=21627&cid=2302809 [slashdot.org] as slashdot covered this exact topic quite a lont time ago: http://ask.slashdot.org/article.pl?sid=01/09/14/1516207 [slashdot.org]
    • Gray is a color, grey is a colour.
  • Easiest (Score:5, Funny)

    by kdogg73 ( 771674 ) on Tuesday April 08, 2008 @10:36PM (#23008086) Homepage
    Like my porn, it's black on white.
  • #000000 (Score:3, Insightful)

    by proverbialcow ( 177020 ) on Tuesday April 08, 2008 @10:37PM (#23008096) Journal
    Black background; font in black.

    You know what? Just turn the monitor off and go look at something with depth-of-field.
  • Not color (Score:5, Interesting)

    by Ironsides ( 739422 ) on Tuesday April 08, 2008 @10:39PM (#23008120) Homepage Journal
    Brightness is the best control for eye strain. I usually lower the brightness to it's minimum and adjust the contrast accordingly. Less light lowers the strain to me.
    • Re: (Score:3, Informative)

      by jthill ( 303417 )

      Seconded. Monitor at 50-60% bright, color temp at D50. Give your eyes a while to adjust (as in, give the cramps a while to subside), maybe a day or two.

      I've still got my decent CRT from ... 1998? 1998. Black-on-white for documents, green-on-black 10pt Courier for terminals, syntax coloring is ok mostly. I miss the layout tweaking I could do on Apple's Terminal; line- and letterspacing with sliders let me get my setup Just Exactly Right. It matters.

  • Why, Pink of course (Score:5, Interesting)

    by vivin ( 671928 ) <vivin@paliath.gmail@com> on Tuesday April 08, 2008 @10:41PM (#23008134) Homepage Journal
    Like here [userstyles.org].
  • Green on Black
    Green is right in the middle of our visible spectrum which makes it the easiest for our eyes to pick up.
    As for which is healthiest for the eyes, probably listening to an audio-book version of the same text...
  • by The Ancients ( 626689 ) on Tuesday April 08, 2008 @10:43PM (#23008156) Homepage

    There are so many variables to this.

    1. What medium are we referring to? CRT monitor, LCD monitor, printed matt page, Hi-gloss paper?
    2. How much ambient light is there?
    3. What type of ambient light is there? Incandescent, fluorescent, halogen...?
    4. What is 'a long time'?
    5. Who are we talking about? A 7 year old child, a 30 year old office worker, a 50 year old proof reader...?
    Answer those questions and we won't all be shooting in the dark.
  • i find bright red letters on a bright blue background to be quite soothing. try it sometime, i promise you will thank me
  • Personally I prefer a black background, large (14+ point) bold font, and syntax coloring with every color of the rainbow above #999999. The colors and contrast help keep my eyes interested on the average 11+ hours per day in front of the (LCD only) screen. The black background helps prevent eyestrain.
  • by DodgeRules ( 854165 ) on Tuesday April 08, 2008 @10:48PM (#23008204)
    ... then shake the monitor.
  • by BlueParrot ( 965239 ) on Tuesday April 08, 2008 @10:48PM (#23008206)
    What is "best" will clearly depend upon what criteria you consider. Are you talking about a combination that is teh least likely to lead to damage to the eyes, the combination which causes least pain while reading, or the combination that is most comfortable? Does psychological factors count? Is your userbase young, old, mixed? I would imagine the answer could differ depending on these cases.

    The only thing I can tell for certain is that the claim that looking at black on white text on a screen is like starring into a light bulb is complete nonsense, and it is very easily confirmed that the two are nowhere near the same by simply looking into a light bulb ( thou it is probably best to limit such experiments in order not to damage your eyes ). While your pupils can somewhat adjust for the incoming light, starring into a light bulb at short distance will almost certainly overwhelm your eyes with light, while looking at the computer screen does not.

    The fact that a computer screen emits light does not in itself mean it will be "brighter" than a paper. It can as an example be very difficult to read some LCD screens outdoors because the relatively faint light they emit is completely drowned by bright sunlight reflected off it's surface. Now, while it may or may not be true that it is "not good" to have all light coming from only one place in front of you (which would appears to suggest having a lit computer screen in a dark room is bad ), this could be easily avoided by simply adjusting the surrounding illumination and screen brightness, and I find it very doubtful that there is much a web designer can do to optimise his webpage for every single situation since users will change the brightness and contrast of their monitors.

    As a pure guess, I would imagine that weather your color scheme is familiar, if your font is large enough, and the reader's "taste" has a much greater impact than most physiological effects, and thus I would recommend a black on white color scheme with a clear simple font of sufficient size. Most people find it acceptable, and there is as far as I know little evidence that it should be troublesome.
  • by unfunk ( 804468 ) on Tuesday April 08, 2008 @10:49PM (#23008216) Journal
    The human eye is naturally lazy, and likes to look at things that do not cause it to send strong signals. To that end, a black background is essential for "easy on the eyes" formatting. From there, pretty much any light colour can be use for the text.
    When I was in uni, I used to buy special black paper "visual arts diaries" and write my class notes using a gold, silver, bronze, or plain white ink pen. This had the effect of making my pretty poor handwriting easier to read for most people, and also reducing the effects of my dyslexia; I would make less errors like inverting a series of numbers as I wrote them down and the like.
    • by tlhIngan ( 30335 ) <slashdot@nOSpam.worf.net> on Wednesday April 09, 2008 @12:02AM (#23008766)

      The human eye is naturally lazy, and likes to look at things that do not cause it to send strong signals. To that end, a black background is essential for "easy on the eyes" formatting.

      Actually, the problem is, people don't use light-on-dark properly, which makes it even harder on the eyes. If you use a thin font like Heveltica or Arial, white-on-black causes the letters to turn into a light grey. The thing is, the black "creeps" onto the lighter color. The general hints have been to either use bold, which fattens the letters enough to offset some of the creep, make the font size larger, or choose a fatter font. All of this helps offset the creep - it's only at the larger sizes does the effect of the creep become less noticeable. It's why I hate when Courier is used as a default font - it's damn hard to read on a black background. On Windows boxes, I much prefer the fat and easily read FixedSys.

      But there are tons of contrasty color combinations. White-black is generic and isn't eyecatching, but great for long sessions. Colors like Yellow-on-Blue are easily read, and the blue doesn't actually "creep" into the yellow too badly. Yellow-Red and Yellow-Green work well too. But yellow can be quite tiring to read.
  • For different working environment, e.g. with different "general background" color/brightness, you may need different color combination.

    Well, nothing could prevent the eyes' fatigue if you keep on looking at the screen too long.

  • by The Ancients ( 626689 ) on Tuesday April 08, 2008 @10:53PM (#23008264) Homepage

    ...because none of us have RTFA - as there isn't one.

    I have found various contradictory recommendations...

    Err, that's nice. Where's the links?

  • I have experimented with many color schemes on several websites I run, which tend to be very text-intensive. I've found I prefer black on light gray. Click the link in my sig for an example.

  • by neapolitan ( 1100101 ) * on Tuesday April 08, 2008 @10:54PM (#23008272)
    I'll chime in as a physician.

    I always wondered in medical school what causes eyestrain -- your mom probably told you "don't read in poor light," but since the photons are easily sufficient to give an image on your retina, this didn't make sense to me.

    It turns out that your eye muscles have a difficult time obtaining a rapid and precise focus with poor light, which gives less contrasts on the edges that are detected for sharp focus. In low light conditions, the eye muscles are rapidly focusing back and forth, and these micro-contractions can fatigue them similar to the other large muscles of your body. As an analogy, imagine walking on level ground versus on a balance beam. You are constantly contracting different adjustment muscles to walk on a balance beam, using more energy and promoting fatigue.

    So, in answer to your question, you would want a high-contrast color scheme to make it easy for your eyes to focus on the letters. "Duh," I hear you say.

    Next, I would recommend minimizing the difference in brightness between your monitor and the outside environment and its background. That is, in a dark office have a dark monitor, and in a bright office, a bright one. Why? Well, same reason -- your eye muscles have to dilate your pupil every time you look away from a bright monitor to a dark monitor. More contractions / adjustments -> more fatigue. Not only that, but the high brightness contrast will give ineffective normalization of light across the eye receptors and could cause headache.

    Regarding your study question -- difficult to fund, and difficult to accomplish. I guess you would have to divide several hundred office workers, and try to have them work the same hours under same conditions with different fonts, and then ask a subjective question regarding symptoms. It could be done, but I am not sure of any well-performed efforts that have addressed this question.

    In summary, I would just choose contrasting colors that you like or find subjectively pleasing, and then keep the brightness on your monitor appropriate for ambient lighting. Also, don't forget to focus on the numerous other ergonomic factors on your workstation. I see a *lot* of people with bad backs from the workplace, but there are a lot of 80 year old secretaries that are not blind.

    Cue the contempt for expertise from the anti-intellectual crowd now. :p
    • by skiingyac ( 262641 ) on Tuesday April 08, 2008 @11:30PM (#23008560)
      So, based on your medical expertise, you are saying if it hurts when I do X, I shouldn't do X?
    • by Skapare ( 16644 ) on Tuesday April 08, 2008 @11:54PM (#23008722) Homepage

      You are on the right track but there is more. Yes, higher contrast is better than lower contrast. But how this works with color is complicated.

      One big issue is that the eye is not perfect optically. It cannot focus all colors at the same focal plane. Just how well it does varies by individual and the optical conditions of their eyes, and the quality of corrective lenses (which usually make it worse with respect to the ability to simultaneously focus all colors).

      An important factor to consider here is which color or colors the difference is at the edge being focused on. For example in the "hot dog" pattern that has been mentioned in a reply here, the difference is actually in green. If the red level of the yellow part is exactly the same as the level of the pure red part, then all the difference is in green and this is an issue of green contrast. Yellow on red like this is essentially the same as green on black ... except that the extra red light with yellow on red causes the iris to close down more than the darker green on black would.

      I find blue to be the worst to focus with. That may be because my sources of blue light are not sufficiently narrow band in the spectrum. Being spread out over the spectrum, it basically comes in fuzzy. Blue is also lower in contrast.

      Green (be it green on black or yellow on red or even cyan on blue) is better.

      Red seems to be the best in terms of focusing a sharp defining edge. You get red contrast with red on black or yellow on green or magenta on blue.

      Unfortunately, effective contrast goes down when extra light is added in other colors. So you have to find a balance trading off the sharpness of the edge vs. the contrast. I've found a good compromise in orange on dark green (the level of green in the orange is the same value as the green background). Think of the orange in a neon sign on the green felt of a pool table. Then when I need to highlight something, I shift over to pink on cyan ... basically add the same level of some blue to both the orange and the dark green.

      A related issue is light quality when reading a book or newspaper. Usually we are stuck with black letters on white paper. The consideration is then what type of light. I find that incandescent light, or sunlight, works nearly best for me for long term reading. Fluorescent lighting is worse. Ironically, I find high pressure sodium vapor light is about as good as, and sometimes somewhat better than, incandescent light.

      To understand this, look at the spectrum. Incandescent light has a fairly even level through all light wavelengths. This makes those black on white edges a bit fuzzy. But fluorescent light has two narrowband peaks at a red and green wavelength (the blue is broader). This can make the text edge sharper ... twice. The eye ends up with two contrast edges. I believe this increases the eyestrain by causing the focus to be constantly jumping in and out to alternate the focus on the two different edges. It's a very small adjustment, but it is there at least for me. With incandescent light, it just settles in the middle of the fuzzy range and doesn't change much. And this is affected by how much light there is, which dictates how small the iris becomes. Higher light levels with a smaller iris won't change the effect from fluorescent as much as for incandescent, since with fluorescent the two contrast edges are already rather sharp due to the two narrowband spectral peaks. But for incandescent, the high light level helps (up to the point that intensity is too stressful).

      This is why I believe we still need to keep some incandescent lighting around for reading and other close/fine work for long periods of time. I get a headache when working on things I need to look at closely when doing so under fluorescent light. The onset is about 25 to 45 minutes. I don't get the headaches under incandescent. And I have verified that the flicker is not the cause. White LEDs

  • myspace (Score:5, Funny)

    by timmarhy ( 659436 ) on Tuesday April 08, 2008 @10:56PM (#23008296)
    Just look on myspace, then do the exact oppersite.
  • by ubernostrum ( 219442 ) on Tuesday April 08, 2008 @10:59PM (#23008326) Homepage

    There is no best set of "colors" for foreground/background, as evidenced by conflicting studies which tried to determine what that set was. Rather, what's important is contrast between the colors so that you can easily distinguish what you're seeing. So long as you maintain contrast, the choice of the specific colors is entirely subjective and up to you.

  • by Saeger ( 456549 ) <{moc.liamg} {ta} {jllerraf}> on Tuesday April 08, 2008 @11:01PM (#23008344) Homepage
    If you stare at text all day long, I've found that high contrast (black on white default) and high color saturation (brightly colored syntax highlighting) is very tiring. Turning both down a notch goes a long way for extending readability.

    My terminals all use a light white on dark grey scheme, and my preferred vim color scheme has been ps_color [vim.org] for quite a while. (here's a useful site for visually comparing a ton of color schemes (in iframes) all at once: http://www.cs.cmu.edu/~maverick/VimColorSchemeTest/ [cmu.edu]. )
  • by xixax ( 44677 ) on Tuesday April 08, 2008 @11:07PM (#23008404)
    ColorBrewer http://www.colorbrewer.org/ [colorbrewer.org] has some of the answers. It will tell you about how well human eyes will be able to discern a colour scheme on various devices. It won't say much about the effect of staring at a particular colour scheme for hours.

    I loved my 21" Eizo greyscale monitor. As a monochrome monitor, it had no colour gun registration issues and the text was razor sharp. It also supported 1600 x 1200 at a time when most people aspired to own a 1024 x 768 17" CRT. That is, the design and quality of the output device is also important for long term eye friendliness.
  • by Amigori ( 177092 ) * <eefranklin718.yahoo@com> on Tuesday April 08, 2008 @11:10PM (#23008426) Homepage
    I'm going to assume that you are looking for a referenced scientific/academic study which will tell you what's best for your eyes. And to that I have no answer. But I do have some anecdotal personal history and a few thoughts.

    Call me old, but I've always preferred Grey lettering on a Navy background ala Word Perfect 5.1. At least when working on documents where graphics and colors are unimportant. I still keep Word configured that way to today. People accustomed to Black on White think I'm weird(er) for using it that way.

    Or when I'm using a terminal, I usually setup a Green on Black color scheme, but Amber text would also be nostalgic. Even a shade of Grey on Black for an alternate nostalgia. SunOS was Black on Grey

    My question(s) to you, what are you working on? Is it code? In an IDE or xterm? Do you have multi-color themes, like in an IDE? Or graphic design with lots of colors at once, in which a medium grey is usually standard? Working in a brightly lit, fluorescent bulb cubicle, an office with natural light, a basement with incandescent lights, or a dark room lit only by the neon/led/ccd bulbs of your case mods? These variables could effect your decision as much as anything else.

    I think the best way for you to figure it out 'scientifically' is to come up with 5-10 combinations, try them each day at work for 1-2 weeks, and record your thoughts in a journal every hour or so. "Is this comfortable to look at? How's my eye strain? Can I reliably read what I'm doing? etc." Then pick your 2 favorites and try them each for a week straight, again making notes. Then decide on one. You can find what works for you over the long hours. I'm certain that my preference is different from yours. Obviously, you'll need to pick colors with higher contrast to each other, as Lime Green text on a Lemon Yellow background would probably be a difficult setting to get much done in.

  • by Ron Bennett ( 14590 ) on Tuesday April 08, 2008 @11:16PM (#23008480) Homepage
    When determining the "ideal" text colors for a website, one needs to take into account that many people have color blindless.

    Furthermore, simply choosing contrasting colors won't work - ie. red on green is bad, red on blue is bad, etc.

    With that said, some of the color combos mentioned, such as black/white or green/black often work well - easy to read by most all people.

  • x fonts/bg I use (Score:4, Interesting)

    by Wansu ( 846 ) on Tuesday April 08, 2008 @11:22PM (#23008526)
    For xterms,

    green on black
    black on wheat
    white on navy
    cyan on black
    orange on black

    I use white on navy for emacs.
  • by ip_freely_2000 ( 577249 ) on Tuesday April 08, 2008 @11:24PM (#23008538)
    That font usually sends me into an epileptic seizure resulting in a day off work.
  • by stewartjm ( 608296 ) on Tuesday April 08, 2008 @11:58PM (#23008740)
    Yellow on Dark Blue. Especially for terminals and editors.
    • Re: (Score:3, Insightful)

      by John Bayko ( 632961 )
      Before GUIs and the attempt to look like paper, this was pretty much universally accepted as the best colour combination. It's was used for WordPerfect, IDEs, BIOS configuration screens, custom applications, and others, and is the reason the Windows "Blue Screen of Death" is blue. Also partly why most VCR programming and setup screens are white on blue.

      I'm amazed that knowledge so well known at the time has so completely disappeared that it's as if it never existed. GUIs took on other colour schemes for o

  • by wrfelts ( 950027 ) on Wednesday April 09, 2008 @12:01AM (#23008760)
    After 24 years of this, the best answer is, "it depends." The common Black-on-white that is most prevalent these days stinks. The idea is to emulate paper, but with a radiating screen, that's a bad idea. Thus, e-paper. From the older interfaces, these combinations worked best:
    • - Bright yellow crisp mono spaced fonts on a dark blue background. This is great for long work hours without sucking your eyes out of the sockets.
    • - Bright white on dark blue. Same reasons. These two combinations, combined with white or yellow on black for highlights, make a good simple combination.
    • - For low-light conditions, such as an emap in a car, go with the traditional green on black or amber on black. Amber is prettier but harder to focus on quickly when glancing. Green is definately better. The current mapping systems with bright backgrounds are only good for daytime driving. The brightness of the screen causes temporary night-blindness when glancing back and forth at night.--very dangerous--
    • - For modern web and client app interfaces, good contrast without major glare is important.
    • - Bright blues are pretty, but are painful to a large percent of the population when exposed over long periods. It has something to do with the monitor focal point regarding blue light. Ask an expert on this.
    • - Use semi-bright backgrounds, but not glaring. Muted (not primary) pastels with a crisp font are good. Examples include "dusty" pinks/salmons or dusty greens, yellows, warm blue-grays serve as good majority backgrounds where whites (unless muted) should only be used for highlights.
    • - You need to make the fonts crisp and readable. Contrast the colors without causing the "spectral blur" that make it look like a "rainbow" on the edges. It may be a cool effect, but it causes eye strain.
    • - Compliment the colors with the expected environment spectrum. An office typically has cool (read cheep) fluorescent lighting and drab office colors. Use a warmer set here. For a home application, use cooler colors due to the typically warmer environment. The contrast is more appealing.
    • - Just as you contrast the colors with the environment, compliment the hue and brightness. A bright area should have a bright screen to match where a low light area should have a darker interface to reduce eye strain.
    Generally, it takes some practice and a lot of input. Some things are often overlooked. A good example is flashing colors, images, or fonts. Just don't do it. These cause huge eye strain and can even cause epileptic seizures. Layout, also is usually an afterthought. This was just as true back when all computers were dumb terminals attached to a mainframes. Most programmers just stink as designers. Clearly delineated layouts are ***ALMOST*** as important as the color scheme. Remember the old timers' rule of thumb. If a novice computer user who knows nothing of the business background for the application can easily explain to you what the application is for and how to use it, then, and only then, it's a good interface.
    • Re: (Score:3, Insightful)

      by elb ( 49623 ) *
      Homeskillet, you didn't cite any references. Why should we believe you? The OP asked for "medical" references, by which I'm sure s/he was hoping for actual journal articles or other peer-reviewed information.

      Clearly delineated layouts are ***ALMOST*** as important as the color scheme.

      It sounded like the OP was talking more about the effects of color & contrast on legibility. Which is not exactly the same as asking about color scheme (with its branding implications). I inferred that the poster was asking

  • by elb ( 49623 ) * on Wednesday April 09, 2008 @01:24AM (#23009418)
    I cunningly did a few searches through the ACM library and scholar.google.com. For example:

    Text - background polarity affects performance irrespective of ambient illumination and colour contrast. [nih.gov]

    In a series of experiments, proofreading performance was consistently better with positive polarity (dark text on light background) than with negative polarity displays (light text on dark background). This positive polarity advantage was independent of ambient lighting (darkness vs. typical office illumination) and of chromaticity (black and white vs. blue and yellow). A final experiment showed that colour contrast (red text on green background) could not compensate for a lack of luminance contrast. Physiological measures of effort and strain (breathing rate, heart rate, heart rate variability and skin conductance level) and self-reported mood, fatigue, arousal, eyestrain, headache, muscle strain and back pain did not vary as a function of any of the independent variables, suggesting that participants worked equally hard in all experimental conditions, so that the interpretation of the primary performance measure was unlikely to be contaminated by a performance-effort trade-off.


    A study of reading time and viewers' preferences for a variety of combinations of character-background chromaticity for small traditional Chinese characters. [nih.gov]

    The purpose of the experiment was to investigate the effects of chromaticity combination on reading speeds and subjective preference ratings for small Chinese characters. The experiment was 7 (text chromaticity) x 7 (background chromaticity) split-plot design. Analysis of variance showed that the text chromaticity was not significant, but background chromaticity was. The findings suggested that achromatic color was the most effective background chromaticity with lower reading time and had a higher preference rating; however, the highly saturated short-wavelength blue was least effective.

    but don't let me do all your clicking for you:
    http://scholar.google.com/scholar?hl=en&q=legibility+of+color+combinations+on+screen&spell=1 [google.com]
  • by multimediavt ( 965608 ) on Wednesday April 09, 2008 @10:58AM (#23012992)

    Readability and eyestrain are always at odds with each other. For readability purposes you want very high contrast between your foreground (text) and background colors. Obviously, white-on-black or black-on-white are the best choices for readability. The problem is over long periods of time high contrast viewing creates eye strain. This is why legal pads are yellow, for instance. The slightly lower contrast between a yellow background and a dark foreground reduces, but does not eliminate eye strain. The problem recurs at the other end of the spectrum if you have too low a contrast between your foreground and background. Your eyes strain to read the text and it makes things harder to read, period.

    As far as colors go, the bottom line depends on the individual. We all see things a little differently, literally! Our visual acuity and duration to eye strain are metrics that do not necessarily apply to everyone and you really have to experiment to find out what contrast level works best for you.

    The font issue is a little more defined. Proportional serif fonts (Times, Garamond, etc.) are good for print applications and are the most commonly used in printed publications. Proportional sans-serif fonts (Verdana, Arial, etc.) are best read on computer screens because of the dithering that often occurs to serif fonts. They are also easier to read on computer screens because the characters are more easily recognizable in the simpler, sans-serif form.

    That's about all I can share on the subject. There are some well established guidelines, but because every human being is a little different there aren't any real hard and fast rules.

In seeking the unattainable, simplicity only gets in the way. -- Epigrams in Programming, ACM SIGPLAN Sept. 1982