Optical Illusions and Glossy Displays

| Analysis

I have a theory, now, that the reason some people don't object to the glossy screen on modern displays, including Apple's, is because they have the mental ability to block or filter out reflections, much like the shift in appearance with some optical illusions. I don't have a any scientific evidence for this, but I did notice the other day that I can block out or bring in the reflections myself at will. Perhaps that's why I don't mind, and fact prefer, glossy screens. Apocryphal evidence also supports the theory.

At Macworld yesterday I was chatting with Rob Griffiths who mentioned that a friend of his just doesn't "see" the reflections. He wonders what the problem is that others complain about. On the other hand, Rob himself sees every tiny light bulb reflected in the display, and it drives him crazy.

As soon as he started chatting about it, I realized that the reflections of the overhead fluorescents snapped into view for me. Then I made them go away, without affecting my view of the content on the screen.

"Aha, I thought. It's the same process that allows some people to switch the view of optical illusions that can be seen both ways." For example, in the cube below, is it a cube floating in space with a chunk out of the corner? Or is it a cube resting in the corner of a three sided backdrop? With practice, you can force the illusion to change back and forth.

Illusion Cube

I haven't explored this any further or spoken with any scientists who specialize in human vision. For now, it just a theory that some people, like me, can enjoy what a glossy screen does in low light yet not object when there are reflections. Can you make the glossy screen reflections go away and reappear at will? Let me know, and I'll see if I can find an expert who can shed some, um, light on all this.

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As an optical physicist, I’ll make a scientific wild a** guess or SWAG.  You tend to only notice items to which your eyes are focused.  Good focus does not just come from your ability to read with one eye, it also comes from the stereoscopic vision coming from two eyes.  Since reflections are usually in the background, they are on the order of 6 feet or more away from the screen where you are usually focusing on something only around 18inches away.  Not only is the reflection blurry, but is is a double image when merged from the two eyes together, and the brain prefers the two images that line up (being the screen at which you are looking).  As a result, when you focus on the reflected object, you quit noticing (or have less notice of) the text or object on the screen.


I love optical illusions, there are lots to see on the web, my favorite site is Akiyoshi’s illusion pages

Maybe all that mind trickery is why the glossy screen on my iMac doesn’t bother me. I’ve trained myself to be able to ignore it? No, most would say I’m too dumb to notice it, but like you, if I want to, I can check myself out in the display.

I used to do color perception research and I would chuckle when another researcher would sit down to do some visual experiments wearing a bright red or yellow shirt. They should know better, that shirt will effect the results. But they don’t notice it.

I’ve seen the same thing happen in a color-controlled graphic-arts setting. They’ve calibrated their monitors, they are judging proofs under controlled lighting and reducing the other ambient lighting in the room, and then they wear some loud color!

But, they don’t see it. Their mind neutralizes the color shift (until of course they change lighting conditions and look at their completed work and blame the printer calibration or profile!).

But, point it out to them, and some people then can’t help but see it all the time. Then it drives them crazy.

So my anecdotal evidence agrees with yours Mr. Martellaro. The unconscious brain can do wonderful things to alter perception, but the conscious mind can ruin it too.

Free your mind, and the gloss will follow!


I don’t mind glossy screens at all, perhaps due to:
1) They have been the norm for high-quality, color-accurate display ever since there were computers.
2) Working in graphic design, I am very used to them.

For me, switching from a high-end CRT to a glossy flat screen was a very small change indeed.


well my eyesight is so bad, if I don’t wear specs (I don’t when using a screen) everything in reflections is one big blur, so glossy works for me!!

D Baddorf

Or is it a little cube balanced on the point of a bigger cube?

James Bailey

Are you suggesting that some people can’t make the cube perspective change at will and that those people also can’t mask out the reflections?

If so, that is an interesting hypothesis that should be easy to check online with a simple poll.

I for one can switch the cube perspective at will and I don’t find the high-gloss MacBook screen to be a problem. As a matter of fact, I love the MacBook screen. I don’t see reflections unless I want to.


Well, we’ve been watching glossy television screens for years. I know I block out all but the most egregious glare.


I have a theory that glossy displays are the worst thing for people who push pixels for a living, which is shameful since Macs have always been the de facto for the print industry.

Having to block out the reflections (or not being able to) is bad, but not as destructive to color accuracy - as a monitor that displays over-saturated hues.

Or is it a little cube balanced on the point of a bigger cube?

I had to do a double take since you mentioned, but no. Look at the shadow in relation to the luminosity on the sides of the cubes.


There is nothing fancy going on here, John. You are able to “filter out” the glare because you are focusing on the SCREEN, which is closer to you than the lights that are reflecting off the screen, which are FURTHER AWAY than said screen (and which are therefore out of focus and not so noticeable.) QED.


Even the old CRTs had anti-glare screens, so RonReed is simply wrong that “They have been the norm for high-quality, color-accurate display ever since there were computers”.

Moreover, high-end editors and graphics professionals use a hood on their display to completely remove ANY glare whatsoever.  This is standard practice (but apparently not for Ron) for achieving color fidelity on calibrated displays.

xmattingly is correct that the glossy displays over-saturate hues and that having to block out glare is a bad thing.  We should not have to resort to mind tricks to get around glaring (pun intended) inadequacies in displays.  Hardware calibration will help with the saturation problem, but a hood is absolutely necessary to remove glare when doing critical work.  Unless you purchase a third-party matte display of course.


OMG!!  I’ve got a glossy screen!

OMG! OMG!  I’ve been using it for over a year!!



Oh and bye the way, did anybody happen to notice that the entire Apple area at MacWorld had the florescent lights turned off so that the area was semi-dim, with spot lighting only over the area where people were standing and looking at the Macs.  This of course made the glare problem on the displays much less noticeable, but is hardly a real-world lighting situation.

Those displays are great for home use, but terrible for professionals, despite what some claim.

Lee Dronick

First of all the shape is a hexagonal rivet head with a inverted three sided pyramidal dimple in the center, However, I too can change what I see there, including various cube arrangements.s

I have a one of the new iMacs with the glossy screen and so far glare has not been a problem. However, at my desk I have my back to a wall with the room lighting in front of Mac, the screen only gets diffused light. If I change my angle of view to the screen then I notice the glare. There are reflections on the screen, but as with John I have been filtering them out.


I have a glossy 24” and 95% of the reflections don’t bother me.  I have considered this issue also, and I know you are correct.  If I look for the reflections, I will see them.  If I don’t, I won’t.

It like talking to someone at a cocktail party.  You hear the person you are talking to, and you’re vaguely aware of the party noise, but it doesn’t impinge on your space at the level of hearing all the other conversations.  Unless you want it to, or unless something unexpected happens to change your focus.


The problem with glossy for color / creative work is not the reflection, it’s the change in color gradation from bottom to top. For basic daily surfing and such it doesn’t matter, but big projects that need accurate tones suffer without the matte.


The explanation for this phenomenon is that the intended screen image is effectively quite close to the observer. The reflections appear to come from far behind the screen… as far behind the screen as the actual source is in front of the screen! Therefore, when one focuses his eyes on the screen, the reflections (which appear far behind the screen) are out of focus…

This ability to essentially eliminate screen reflections diminishes as the screen is moved farther from the observer (not usually the case with PCs).  However, glossy TV screens can become problematic when the viewing distance is often much greater.

Neil Anderson

“...but a hood is absolutely necessary to remove glare when doing critical work.”

And don’t forget to dress in black. Ninja photo editor reporting for duty.


@KEITH:  “The explanation for this phenomenon is that the intended screen image is effectively quite close to the observer. The reflections appear to come from far behind the screen?” 

The phenomenon is Depth of Field, same as in using a camera, and you described it quite well.  Those of us using video to make movies are obsessed with reducing the DoF in order to partially emulate the look of real film cameras.  Since the eye is analogous to a camera, this got me thinking. 

One of the things we can do to reduce the Dof , and make stuff in the background (real or reflected) blurry, is to open up the iris.  Sometimes we have to reduce the amount of light on the subject to make opening the iris possible, without completely blowing out the whole scene.  We often do this with the addition of filters in front of the lens, and/or by reducing the amount od light.

Since the human eye is always set on automatic, the only way to do this is reduce the amount of light coming from the monitor.  Although you can use the Displays Preference, I have been using the app, “Shades” to do this and to control the color temperature to some extent.  I installed this because the new iMacs are VERY bright. This may also be the reason I have no complaints about the glass reflections.

I suspect that all those who have trouble with the reflections are the same people who complain about the brightness.  Except for image Pros, I suggest lowering the brightness, and doing it via Shades, which can also give you control over which colors are most prominent.  And remember, as your screen gets dimmer, you irises will open up to compensate, which in turn, will reduce the DoF, and those annoying reflections.

Give it a try for a day or so, and let us know if this works.  I for one would be very interested in the results.



I am puzzled as to why it’s believed that glossy screens produce poor colour. Once you’ve run a calibrator on it to get the response curves there should be no issues. Even when I had CRTs I used a hood from time to time. I’ve not come across the issue with my matte or glossy screens I’ve used and I’ve not had a problem with colour at press time. Years ago with video production all the SONY Trinitrons we used were glossy (so we could see our perceptive blacks). Mind you we sat in booths with as much low and indirect light as possible but we were perfectly capable of getting things fine with hue/colour/saturation.


I am puzzled as to why it?s believed that glossy screens produce poor colour.

Not poor color. Oversaturated color. Color that is impossible to produce through offset printing. No amount of calibration will compensate for that on a glossy display.

Carlos Z.

Un poco m?s de investigaci?n!! eso es psicolog?a b?sica, se?ores.

La habilidad de bloquear reflejos no tiene absolutamente nada que ver con el (problema del) exceso de contraste de una pantalla glossy. Cualquier dise?ador gr?fico sabe eso; por ejemplo, incluso los monitores CRT profesionales de dise?o gr?fico ven?an en el pasado con una capa de anti-reflex sobre el vidrio de la pantalla, Para un profesional (es decir el p?blico objetivo de las Macbook Pro) la exactitud del color est? muy por encima del gran contraste de una pantalla glossy, porque no vamos a comprar esa computadora para ver una pel?cula, sino para trabajar artes, d?jenle el uso ligero a los usuarios de las MacBook, y hagan que las MacBook Pro sirvan para los pros.

Si quieren hablar de gustos y preferencias, me parece muy bien. Pero no los justifiquen con evidencias que nada tienen que ver, menos a?n con ejemplos que nada tienen que ver con estas ?ltimas. Cojan un libro sobre dise?o gr?fico, otro sobre psicolog?a y aprendan un poco.




Let me get this straight.  You actually think that an identical (raw) panel suddenly produces ‘oversaturated color’ because someone put clear glass in front of it, instead of a matte piece of plastic?

It’s more likely that you were first exposed to *cheap* panels in glossy form, and have drawn your conclusions from there.

A good, quality panel will produce good color saturation *regardless* of whether the material put in front of it is shiny glass or matte plastic.  A cheap panel will not.

Saying ‘matte good, shiny bad’ is about as accurate as saying ‘15” CRT is bigger than a 14” CRT’ back in the mid 90s.  (In case you haven’t been into computers for that long, I’ll give you a hint.  CRTs *used* to be measured by the diagonal of the *tube*, not the visible or even *usable* screen surface.  My first 15” monitor had a usable diagonal of 13.2”.  My first 14” had a usable diagonal of 13.9”.)


@ Vocal Vomit:

It’s more likely that you’re reading into what I said, and adding your own invective. I never said glossy’s are “suddenly” worse than matte displays; they ARE worse at giving you an accurate projection for printing. No display is ever going to be reliable at reproducing CMYK color, but for those of us in the business, the latest trend is a step backward.

Do some research on the CMYK and RGB color models, get a clue about the physics of light reflection, and quit running your mouth off like an ass.


Fully saturated colors are colors that have no admixture of “white.” If you want to lower the saturation of your reds, you do that by dialing up green and blue. If the results are too bright, reduce total brightness. There’s a lot more to color reproduction than that, of course, but no reason in principle why a display can’t be color-accurate without pushing light through a diffuser—which is what an anti-glare coating is.

About perceived reflections: I am oblivious to them, too; or, I can make myself notice them at will. I don’t think this is quite like the Necker Cube illusion. Since we’re guessing freely, I would bet this is more like my ability to go all day long without ever “seeing” my own nose or the frames of my eyeglasses, even though both are in my visual field every moment my eyes are open.

It still matters whether the glare is there. If you have reflections on your screen, they will change your perception to some degree, whether you notice it happening or not. It would seem like that could be fatiguing if uncontrolled.



Wow.  You said, glossy screens give over-saturated color.  I said, poor quality screens give over-saturated color.  You answer a simple statement of fact, and a supposition that you are likely judging an entire class of displays by the low-grade displays that lead the pack, by calling me ‘Vocal Vomit’, and ‘an ass’.

Seriously, who crapped on your keyboard this morning?

Yes, the RGB and CMYK color spaces display both cover overlapping (but different) ranges of colors.  Yes, too much reflection will limit your ability to properly calibrate your monitor.  Neither of those are limited to LCD displays, however.  For *years*, industry wisdom said “You can’t properly color calibrate an LCD!”  Then, decent quality LCDs were produced, and eventually they became the norm in most stuff below the bottom of the barrel.  Currently, top-quality LCDs produce *better* color than CRTs.  Early glossy LCD displays had the low-end panels, and pulled the matte finish to compensate for their low brightness and contrast.  Currently, glossy LCD displays are made with the entire range of panel quality.

Gloss/matte has no *direct* input on color reproduction.  The same raw panel will produce the same quality color whether it has a glossy or matte front.  Poor and/or inconsistent lighting conditions, on the other hand, will have a *huge* impact on color reproduction.

Just a nit, but technically, your nose isn’t in your field of vision unless you cross your eyes (or have an unusually large nose).


@ Verbal Diarrhea:

The condescension and misappropriation of my comment were plainly there in what you wrote. That’s the usual approach of an attention-starved troll: then wow, you act surprised at the response you get. If you don’t want a sharp retort, don’t post like an ass. Grow up.

Glossy displays produce over-saturated color: that is FACT, and has less to do with the quality of the display than the nature of how it projects color or the quantifiable physics of specular light reflection/scattering. Visit an electronics store, or research some articles on the internet for a comparison of glossy/matte displays of identical make & quality. You’re going to find that I’m right: glossy’s do in fact produce higher color saturation than an equivalent matte, and you don’t know what you’re talking about.



Actually, the ‘condescension and misappropriation’ were all coming from your end, xmattingly.  Not too surprising from someone who argues without the ability to resort to the facts.

As a lawyer friend of mine says, “When you the facts are against you, pound on the law.  When the law is against you pound on the facts.  When both are against you, pound on the table.”  You’re doing some mighty fine table pounding there.

The matte surface of a non-glossy LCD is, in most cases, simply a diffusion filter.  (Sometimes, rarely, it also includes a polarization filter.)  That diffusion filter scatters the incoming light to reduce (you’ll note that I didn’t say ‘eliminate’) the reflections from outside light sources.  On the other hand, as a side-effect, it also scatters the light coming from *inside* the display reducing the effective brightness of the panel.

An identical panel with a glossy surface will produce brighter, crisper colors, and have a *greater* range of adjustment for color calibration.

There was a time in the industry that people said ‘computer monitors produce poor color’.  Since then, monitors have improved, changed, and improved again several times over.

Let me say it again.  The glossy/matte quality of a display has *zero* impact on the color produced by the display itself.  A matte display sacrifices some color brighness in exchange for reducing the effects of outside light sources.  A glossy display gives you the full color capabilities of the technology in exchange for having to be more careful about where you position the display in relation to surrounding light sources.

Of course, you’ll come back and call me some more names, and insist (again) that two identical LCD panels, one put into a glossy display, and the other put into a matte display will result in a glossy display that gives you ‘bad color’, and a matte display that will give you ‘good color’.


@ Voice of Unaccountability:

Oh, so the LAW is against me now? Ha! If you want to wax philosophical by proxy of your “lawyer friend”, then I’ll state the obvious: the burden of proof goes to the one who cries fowl. You started this tug of war, my little nugget: since you’re only here to run your mouth off, show everyone how smart you are and find some of these so-called “facts” that a glossy display can be calibrated down to matte-quality saturation of hues. Obviously you’re happy enough talking smack without anything to back it up. Like I said: you’re an attention-starved troll.

Your 2nd to last paragraph goes to show your lack of depth: glossy or matte coating has EVERYTHING to do with the quality of display color, because light has to pass through it and - depending on ambient light - reflect off it… DUH! The case you’re trying to make is fundamentally flawed—the issue isn’t the quality of projected color, it’s the perception of color, and by nature, what you see is affected by the covering and/or coating on your monitor.

Also note that I never said “bad color” or “good color”—I’ve only used the phrase “over-saturated for print”. And again, you twist my words around in a lame attempt to prove a point, for which you have absolutely no reference other than what’s rattling around in your own head. Am I being condescending? You bet I am now—but the misappropriation was entirely yours from the get go.

Of course, you will come back empty handed, and insist that you’re right and everyone else is wrong based on… you guessed! Nothing at all.



“Your 2nd to last paragraph goes to show your lack of depth: glossy or matte coating has EVERYTHING to do with the quality of display color…”

“...you?re trying to make is fundamentally flawed?the issue isn?t the quality of projected color, it?s the perception of color…” 

First, you said it has EVERYTHING to do with quality, then you said quality isn’t the issue.  Which is it?

”...by nature, what you see is affected by the covering and/or coating on your monitor.”

Citation?  Any reference at all?


@  iJack:

This was an argument started by someone else; pick your own battles. I’m also not going to give you a lesson on the physics of light—figure it out for yourself. And reread my posts if you have to: obviously the context flew right over your head.


So, is color that is ‘over-saturated for print’ good or bad?

You’re correct when you say, “the burden of proof goes to the one who cries fowl”.  Oddly, though, *you* are the one who cried fowl when you said, “... Color that is impossible to produce through offset printing. No amount of calibration will compensate for that on a glossy display.”

The burden of proof is upon you.  Produce the evidence.


Oh, and if you could do it without resorting to name-calling that would be nice.  (You’ll note I’m not expecting you’ll be able to.)


@ xmattingly
This is an open forum, bud.  I’ll pick whatever battles I choose.  And I really don’t need a lesson on the physics of light - I am an engineer and a cinematographer, and have a pretty good grasp of the subject. 

What I asked for was some proof of your bold, and somewhat contradictory statements.


@ Shifter of Blame:

Exactly as I predicted: you came back with ZERO reference that glossy supposedly DOES NOT affect color saturation. Thanks for proving me right!

My comment was made long before you showed up. You called it bunk, so YOU are the one crying fowl: therefore the burden of proof lies with you. Obviously, you have no ammo for your point of view, so the best you can come up with is a lame attempt to shift obligation to me. How weak. The ball is in your court and it’s been motionless for a long time now, bubby.

If you have no idea whether over-saturated color is good or bad for print, you never had a clue to begin with. I’d start with learning the difference between the CMYK and RGB color gamuts, what exactly is meant when we say “color saturation”, and why too much of it is impossible to reproduce in a subtractive color model.

Next time you tell someone they’re wrong, why don’t you grow a pair and be prepared to demonstrate WHY they’re wrong, instead of running off at the mouth with nothing to show for it?


What I asked for was some proof of your bold, and somewhat contradictory statements.

Like I said, you failed to follow the context of my post(s). If your grasp of light physics are similar to your comprehension of the English language, then nothing’s going to get through, buddy boy.


I support a print shop that uses intel iMacs with glossy screens.  They have no problems at all calibrating the displays to accurately represent what they get out of their offset press, though they do have to manually calibrate each pre-press station.  And each station is slightly different because the angle of the lights, etc. is different for each one.

The lead prepress technician says the real problem with portables is the changes in ambient light from location to location can alter the perceived color balance of a computer display - far more than the difference between matte or glass. According to him, it is simply unreasonable to expect to be able to start a project at home using incandescent lighting, and finish up at work under florescent lights without expecting to do some serious tweaking on the color balance before sending it to press.

Anyway, he says gloss or matte makes no difference in the end result.  As long as ambient light is constant, any display can be calibrated as needed.


You made the original claim that glossy LCDs cannot be calibrated.  Since then, in support of your position, you have resorted to name-calling, accusations of trolling, and apparent arguing from a (supposed) position of authority.

You have most definitley *not* provided any data or evidence of any sort to back up your claim.  On the other hand: mathue, robofly, iJack, zewazir, and myself *have* provided data and/or evidence which supports our position.

Let’s go over this one last time.
Original claim made by: xmattingly
Explanations why claim is mistaken given by: mathue, robofly, iJack, zewazir, and Voice
Support for original claim provided by xmattingly?: No


@Hypocritical Troll:

Dude, you ARE being a troll - suck it up and own it!

First of all, you’re out of your tree: no one has supplied any of this “evidence” that you’re demanding of me - other than here-say and conjecture, aside from iJack’s reference to a utility that doesn’t do much more than what’s already built into Mac OS.

Second: you took a shot at me—you are the plaintiff (ask your “lawyer buddy” what that means). The ball is in your court, and since you’re too incompetent to pick it up, you can only come back with some ridiculous claims that everyone in this thread has referenced well and cited their sources… except me of course. Hah ha ha… CLEARLY an act of desperation on your part.

Third: according to you, now I’m claiming that “glossy LCD’s can’t be calibrated” at all. Since you can’t follow the bouncing ball, I’m starting to understand why it’s just sitting there on your side of the court.

Fourth: they make pills for your little OCD problem, there.

The biggest hypocritical dweebs demand everyone who contradicts any minutia of their views report a detailed thesis of their POV rather than subscribe to any amount of common sense or logic, OR THE FACT THAT PEOPLE JUST DISAGREE SOMETIMES. And of course, are not obligated to justify themselves by any measure.


@xmattingly and @Voice

The expression is “cry foul” not “cry fowl”, (see http://dictionary.cambridge.org/define.asp?dict=CALD&key=18740 for at least one source).

And would you please drop the insults and disparaging comments and say something meaningful in a calm and respectful way? I am very interested in opinions on glossy vs. matte but don’t care to wade through childish spats to find them.


rjackb said: The expression is ?cry foul? not ?cry fowl?...

Whoops - I don’t know how I overlooked that, but I’ll take credit for it - my bad. For what it’s worth, there HAVE been a lot of bird brained comments floating around here lately. smile

I would prefer to keep threads as an exchange of opinions as well, but I’ll certainly respond to someone who takes a dig at my own. Having said that, there really hasn’t been much discussion here in the vain of what you’re looking for, anyway.

You would probably benefit more from researching articles that compare glossy to matte directly, rather than the reflectivity of glossy screens. Good luck.


Yes, it is indeed ‘foul’, not ‘fowl’.  I quoted xmattingly, and then fluffed it up myself just a couple words later.

I asked, quite simply, if you were seriously claiming what you appeared to be claiming.  (You have since insisted that you are.)  You answered back with insults and invective.  With that in mind I’ll ask a quick question…

What, exactly, did you find rude or insulting about my original post?

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