I don't think the two should be merged. The Disney Digital 3D page is misleading in that it suggests that Disney 3D is an exhibition format. It is a production format. It could be suggested that DD 3D co-opts the RealD brand- however- the real distinction is between a studio's production and a theater's exhibition technology. Napstergirl (talk) 18:26, 12 June 2008 (UTC)[reply]
This article should not be merged with the Disney article. Warner brothers also uses this technology (Journey to the Center of the Earth 3D). Several smaller studios have licensed RealD technology for IMAX films. Merging the articles would give the impression that this was a technology only available on Disney films and was, in some way, different from the technology in non-Disney films. Durnett (talk) 15:49, 23 September 2008 (UTC)Durnett[reply]
It seems as if the DD 3D article has more information on RealD than the RealD article. This information should be moved to the RealD article. There shouldn't be a merge, though, as the technology isn't Disney's. Johhny Ant (talk) 08:26, 2 October 2008 (UTC)[reply]
When I made the merger proposal, I proposed merging the Disney article into this one. Somebody has sneakily swapped the sense of the merger banners. Disney maybe? :-) --Farry (talk) 20:14, 15 October 2008 (UTC)[reply]
Real D is it's own company. "Disney Digital 3-D" is not a technology per se. It's just Disney's brand for their films that implement any digital 3d technology- for now and the forseeable future they're using Real D's technology. Other production companies use Real D as well. Merging would be inaccurate, discussion should be over. —Preceding unsigned comment added by 151.207.240.4 (talk) 23:52, 24 November 2008 (UTC)[reply]
I agree - do not merge, Disney 3D is not exclusively shown using realD format, the recent Bolt 3D release is screened in both realD and Dolby 3D.
FYI dolby 3D can utilise exisiting white screens, but the glasses are more expensive than tyhe realD glasses and are usually re-cycled, RealD requires the instalation of a specialised siver screen to maintain the polerisation, this screen cannot be used for standard 2D presentation. —Preceding unsigned comment added by 81.111.67.66 (talk) 14:43, 18 February 2009 (UTC)[reply]
I've picked this stuff up from blogs, so it's all horribly unsourced. Maybe somebody else would like to try their hand at finding some concrete sources?--Farry (talk) 00:05, 12 December 2007 (UTC)[reply]
RealD's new brand convention is that "RealD" be rendered as all one word in order to facilitate user searches for information on the technology. Napstergirl (talk) 18:28, 12 June 2008 (UTC)
I will do a move in a few days. —Preceding unsigned comment added by Napstergirl (talk • contribs) 18:51, 12 June 2008 (UTC)[reply]
The third paragraph of the Technology section is the heart of this article. Yet it doesn't have a link to an article explaining circular polarization and it does not state whether RealD requires glasses. Someone more knowledgeable on this subject than I should make improvements. David (talk) 13:10, 7 February 2009 (UTC)[reply]
Agreed, after reading this article I especially don't understand the difference between the two lenses of the glasses. The circular polarization article doesn't make it clear how a passive technique can distinguish between clockwise and counterclockwise polarizations. Meekohi (talk) 20:56, 16 February 2009 (UTC)[reply]
Thank you. I have put a note there similar to this.- The actual action of Real D spectacles does not correspond to that of the kind of spiralling waveform described there. Transmitting or blocking of light passed through two filters depends on the direction the light goes through the filters, not just their relative axial orientation, as in conventional polaristion, as if their action is analogous to that of a rectifying diode on direct current. It is not independent of their axial orientation, as it would be if the contrary-rotating spirals analogy were entirely appropriate.
--Hugh7 (talk) 00:57, 11 June 2012 (UTC)
Hugh7, If i understand you correctly, I believe you're mistaken. I wrote the circular polarizer section and unless its wrong, the orientation of the filter relative to the incoming light does not matter. Only the orientation of the initial half wave plate relative to the following linear polarizer matters. Dave3457 (talk) 18:53, 12 June 2012 (UTC)[reply]
There needs to be some sort of explaination as to why this technology hasn't been incorperated into Home DVD or Blue Rays disc of the same title.. —Preceding unsigned comment added by 216.48.130.33 (talk) 14:29, 10 February 2009 (UTC)[reply]
It's not that the technology hasn't been incorporated into the disc's -- the RealD circular polarization projection technology is fundamentally incompatible with today's television sets. The closest you can get to non-anaglyph 3D is using high-refresh CRT's or DLP monitors with active shutter eyewear. LCD monitors are completely not capable of rendering separate left and right images. Moreover, there is no infrastructure to actually deliver the video at the higher frame rate needed for 3D. The DVD/Bluray players don't support it, and the monitor's support for 3D is still not a plug-and-play experience.
A number of movies have been released in anaglyph (Hanna Montana 3D, for example) -- but that is a totally different process from RealD. I'm not sure that the RealD Cinema entry is the right place to discuss that...
The mention of frame rates is confusing, perhaps even misleading. Traditional film (35mm) does run at 24 frames per second, but digital projectors do too, even in 3D. Although there are 48 frames per second in digital 3D, they are in 24 pairs. Each eye still only sees 24. Each frame is flashed 3 times with each flash alternating with a flash of the corresponding frame for the other eye. There are not 72 frames per second, rather there are 72 flashes for each eye per second for 144 total flashes a second. It may also be useful to note that, although alternating flashes for each eye helps reduce problems such as eye strain, multiple flashes of each frame was used before digital or digital 3D. The shutter of a 35mm projector has two openings which flash each frame twice for 48 flashes per second. —Preceding unsigned comment added by 68.74.222.54 (talk) 07:22, 25 February 2009 (UTC)[reply]
-- I'm an edit-noob, so please forgive me when I don't know the customs around here (or how to sign my own comment), but the information contained in the paragraph right above me is exactly what I was missing in the article itself: the (im)possible home use of the exact same technology (i.e. RealD) viewers experience in theaters these days. IMO, this data should be included ASAP, and best in a seperate paragraph under the header "home use" or something like that. Thanks in advance and keep up the good work. -- Frank Kramer —Preceding unsigned comment added by 84.142.150.185 (talk) 11:27, 1 November 2009 (UTC)[reply]
The projector alternately projects the right-eye frame and left-eye frame, and circularly polarizes these frames, clockwise for the right eye and counterclockwise for the left eye.
There are two conventions with regard to the definition of clock-wise and counter clockwise. Refer to the article on circular polarization. Here are some quotes.
Circular polarization may be referred to as right or left, depending on the direction in which the electric field vector rotates. Unfortunately, two opposing historical conventions exist. In physics, astronomy, and optics, polarization is defined..........In electrical engineering, however, ..........To avoid confusion, it is good practice to specify "as seen from the receiver" (or transmitter) when discussing polarization matters.
I'm personally assuming it is from the view of the projector, but the sentence is not absolutely clear on it.
I tried Google searching for the original blog that I got the "clockwise for the right eye and counterclockwise for the left eye" from, but now I can't find it. There are other Real-D writeups on the net that also state that it's that way around, but they postdate my placing it in this Wikipedia article, and look suspiciously like a copy of my wording. --Farry (talk) 15:35, 25 July 2009 (UTC)[reply]
Their website (at [1] ) says "The Right Eye image is circularly polarized clockwise, matching the Right lens in the glasses ... " but the way the diagram is labelled R/L make it look as if the rotation is as viewed from the screen. This seems to be the opposite to the normal optical convention of describing it from the receiver (eye) POV. - Rod57 (talk) 12:37, 1 May 2017 (UTC)[reply]
A 3-slide series of pictures taken with and without a pair of masterImage 3D circularly polarized movie glasses of some dead European rose chafers (Cetonia aurata) whose shiny green color comes from left-polarized light. Note that without glasses both the beetles and their images have shiny color. The right-polarizer removes the color of the beetles but leaves the color of the images. The left-polarizer does the opposite showing reversal of handedness of the reflected light. This wonderful image sequence from circular polarization shows the sense of the MasterImage glasses. Does anyone have access to a European rose chafer beetle to see if the RealD glasses use the same convention ? or any other way to actually test them ? - Rod57 (talk) 12:55, 1 May 2017 (UTC)[reply]
For a while now this article reads like an advertisement. To improve on this I suggest some wikification. I mean links to other wikipedia articles. Some suggestions:
Why is it possible to double the frame rate of a digital projector? Was this option already planned into the device?
I know thin plastic polarization foil, but I do not know thin plastics quarter wave plates. So how much more expensive are these glasses having an additional quarter wave plate?
Digital_cinema#Stereo_3-D_images mentions a zscreen. Can we please specify which one of the two classes of liquid crystals are used. It seems it is the sort not used in notebook displays (nematic vs scemic or so). What does push-pull mean? Are these molecules polarized?
Notebook LCDs are slow when switching from completely black to white. Why is the zscreen so fast? I think it is switching from gray to gray, but so thick that "gray" means "quarter wave".
How did they get the metal screen to reflect equally towards the whole audience?
Thank you, now it is a nice article. Nice references
One reference says that the liquid crystal can be made sufficiently achromatic, I am satisfied.
Newport says:
For example, most plastics exhibit birefringence from stress applied in the manufacture. Plastic wave plate material is available in half- or quarter-wave retardation values in very large sheets. It is inexpensive, but not of the highest optical quality or durability.
One reference says that the residual crosstalk is compensated for electronically. (works if there is not full black or white involved).
--Arnero (talk) 12:02, 7 February 2010 (UTC)[reply]
It's not hard shooting 3D films, but it is hard rearranging the data so it is compliant with the various standards that are in place. And naturally, different standards are found in different patents.
The US Patent and Trademark Office maintains a website [2] for people scoping out patents, and helping them find out who the most recent patentholders, registrees, and transferees are.
The main article leaves out some really useful information, like (specifically) the patent numbers of the methods devised and registered by the patent holders. Rather than have the main article read like an advertisement, the main article would be improved considerably if someone would just go through the main article with a fine-toothed comb, and cite the specific patents being used in RealD Cinema, and put in the patent numbers. Dexter Nextnumber (talk) 01:44, 1 November 2009 (UTC)[reply]
This is an explanation of how circularly polarized light is used to separate left and right eye images.
Circularly polarized light is produced by passing linearly polarized light through a quarter-wave plate (see http://en.wiki.x.io/wiki/Quarter_wave_plate). If the angle of the linearly polarized incident light is at 45 degrees with the axes of birefringence, then the wave will be circularly polarized--any other angle produces elliptical polarization. When the circularly polarized wave passes through another quarter-wave plate the exiting wave is linearly polarized at either in the same or 180 degrees from the original incidental wave (depending on the orientation of the last plate's birefringence axes). If the right-eye and left-eye circularly polarized waves have opposite rotations, the angle of the final linear polarization will be 90 degrees apart. If the quarter-wave plate is backed by a linear polarizer aligned at 45 degrees to the birefringence axis of the plate, only light of one circular rotation direction will pass through. Therefore the right eye sees only the right-eye circular polarization, and the left eye sees only the left-eye circular polarization. The blocking of light depends only on the angle of the linear polarizer in the glasses with respect to the birefringence axes of the quarter wave plate in the glasses and not on the angle of the combination with respect to the incoming circularly polarized light.Gp4rts (talk) 09:58, 13 January 2010 (UTC)[reply]
Thank you, Gp4rts, for your explanation. My problem: I still can’t explain the effects you can get with two glasses. I’m speaking of the darkening effects, not the color preferences. OK: circular polarized light (of opposite rotations) comes in and is made to horizontally polarized light hitting the eye. This effect works in the direction 'outside to eye', not vice versa. Or? I think the filter is asymmetric, as the way the glasses are held matters. 1a. If you hold two glasses in normal position one after another, normal light comes out horizontally polarized after the first glass, which is ok for the second, as this second filter is hit at the normal 'circular' input side. Rotating the second glass just shows the slight variation in color filtering. 1b. If you oppose the second glasses (i.e. world > eye > eye > world sides), the horizontal light from the first can enter the second only if the second is held horizontally as well. If you turn the second filter at right angle, darkness! No matter with which eye. 2. If you stand before a mirror with glasses on, the light from your eye (behind the glass) passes through the filter and comes out circular. The mirror turns around this circularity (does it?), which then is blocked by just this same filter and let pass by the other eye’s filter. Right? It would be lovely, if someone could add something like 'experiments with Real-D-glasses' and explain the effects. All I could do is make the pictures at [[3]] --Fritz Jörn (talk) 07:46, 7 February 2010 (UTC)[reply]
The mirror changes circularity.
I would figuratively say, it saves the circularity, but changes the wave-vector direction. But since circularity is defined with respect to the wave vector, your statement is correct: It changes circularity.
Everything in this subsection seems correct to me. For personal comprehension: Play around with filters and quarter wave plates or do some math with Jones-Matrices. And take some more of your beautiful photos! Sadly we still need a reference for the glasses. None of the references below seem to cover this topic (or I cannot find it => improve inline citing!)
If the lenses cut out the 1/2 of the image that is intended for the other eye, why isn't the image twice as bright when you take off the glasses? For that matter, why is the apparent optical density of the lenses only about 10% when used outdoors? Sunlight has random polarization (for the most part) so if these lenses cut out the image intended for the other eye, they should cut off half the sunlight and make them about 50% density.
I assume the answer is that the polarization is only marginally applied, and that only a small amount is needed in order to provide the effect. But none of the articles on this topic mention this, and I find it confusing.
If you refer to reference (6) you will see that there is light lost from many factors. Only 15% of the light from the projector gets through each glass lens. Much of this is made up by using a high-gain screen. The glasses by themselves pass only 40% of randomly polarized light: 50% for polarization and 80% efficiency. However, a 60% reduction of light to the eye does not look like that much because of the non-linear intensity response of the eye. A 0.3ND filter cuts out half the light but is is very light gray. In the theater, taking off the glasses will increase the intensity by 20% because of glass transmission efficiency, and then a factor of 2 increase because the duty cycle for both eyes is 100%. Again, that will not look like that much to the eye.--Gp4rts (talk) 06:46, 20 January 2010 (UTC)[reply]
I can only speak from experience. When I saw Avatar in this 3D format, I noticed a distinct darkening of the image and apparent reduction of contrast when I wore the glasses. When I took the glasses off, the image restored to a beautiful (and correct) level of brightness and gamma. I never did get completely used to the darker image, so I was dissatisified, and would have preferred some sort of gamma shift in the render or brighter projector. I checked the glasses against a Zone System chart, and they underexpose by one stop. (I'm an ex-photographer, video editor, motion graphics designer and occasional colorist, so I'm used to evaluating images.) Podmonger (talk) 20:05, 1 February 2010 (UTC)[reply]
I just found two nice images (of the Real-D glasses) in the discussion of the German article
Are they a combination of QW retarder film and linear polariser ? Which one is nearest the eye ? For each eye which is the fast axis of the QWP, and the axis of the linear polariser ? Do they both have the linear axis at 45 degrees to the QWP fast axis ? Are the RD glasses using standard photographic circular Polarizing filters ? Photographic filters are used linear at the front, QWP at the back ? RealD glasses seem the other way round. Both eyes appear to have the linear filter passing horizontal pp light - Seems to be a coincidence - not needed for them to work in Real 3D cinema ? (as mentioned in some comments above - could add to article?) - Rod57 (talk) 12:45, 1 May 2017 (UTC)[reply]
With multiple RD glasses are the various optical effects explained by the axis of each component ? (eg rotate front to front (of opposite eyes) gives purple to v dark blue, rotate front against back varies from pale yellow to pale blue). Is this somehow explained by the yellow-green-blue German diagram to the right ? - Rod57 (talk) 17:20, 29 April 2017 (UTC)[reply]
"However, the disadvantage of RealD is that it halves the resolution of the projector.[7] For example, RealD's deployed 2K projectors for 2D (slightly better than standard 1080p HDTV resolution) only provide a resolution of 1K for 3D (close to 720p HDTV resolution).[2] Linear Polarization, such as that utilized by IMAX, does not suffer from this halving of resolution."
NOTE - Somebody apparently doesn't understand two things: 1) press releases can get it wrong and 2) DLP, LCD and SXRD imaging chips have frame rates higher than 144Hz. In the above paragraph about the disadvantage of RealD, all of it is based on Sony's PR hyping about their 4K projector. If Sony is being truthful, then it can only be truthful about their 2K SXRD projector and not 2K projector in general. LCD and DLP digital cinema projectors have a refresh rate of higher than 144Hz. Even the Panasonic PT-AE4000, a home theater projector that costs only US$2000, has a refresh rate of 200Hz. That is higher than RealD's 144Hz. So the statement above based on Sony's PR - that RealD halves the resolution of the projector - is simply not true. —Preceding unsigned comment added by Writesimply (talk • contribs) 04:43, 26 March 2010 (UTC)[reply]
I have personally seen Avatar in both Digital 3D in a RealD equipped cinema with one RealD-equipped projector, and also at an IMAX theatre with two projectors. While IMAX might carry better resolution, I found that they still use old horizontal/vertical polarizaton technology, so that you could not tilt your head or it gets fuzzy and out of focus, and secondly the 3D effect is diminished - not as crisp and popped.
On the other hand the Digital 3D in a cinema with RealD circular polarization was a vastly superior experience in that the 3D effect trully pops out and is sharp and crisp.
You may want to investigate that yourself, as this makes IMAX inferior suffering from older 3D technology, while Digital 3D despite the resolution issue (which is not really visible)
the RealD experience makes Digital 3D superior. Unless the IMAX theatre upgrades its projection to circular polarization, it suffers. I also suspect all IMAX are using horizontal/vertical polarization because of their two projection system. As far as I read, Real-D equips standard cinemas with a Real-D projection splitter.
People traveling to cinema or IMAX should be aware of the RealD glasses - because if they are given anything else, almost guaranteed it is not circular polarization, and their 3D moviegoing experience will leave then something to be desired. Sadly I have seen several comments from some people online saying they did not like the Avatar 3D, and I suspect they saw it at IMAX (for the above reasons).
See http://www.reald.com for more information and to find Digital 3D equipped cinemas.
In some parts of the article, it says that frames for each eye are projected alternately 72 times a second, functionally identical to RealD's old Z-Screen system, which (like all page-flipping systems) rapidly causes massive eyestrain due to the horrible flicker.
In other parts of the article, it says images for both eyes are projected onscreen simultaneously at all times, totally eliminating flicker.
I've removed the latter. Seems to be a load of stuff about the "Sony 3D" system, added by an IP traced to Sony employees, except said employees managed to turn the article into confusing self-contradictory garbage. Sony should fire them if that was indicative of their competence. If they want info about Sony 3D in Wikipedia, then they should create a separate article.--Farry (talk) 19:42, 25 August 2010 (UTC)[reply]
- I changed the image so that the page didn’t look like an advertisement. Note the image has in it the words “The premier digital 3D experience” and so was inappropriate. (It was initially put there by the sock puppet User:爆笑連合 which has since been blocked. (Moment in edit history it was added >> [4])
)
- moved information about the projector down into the technology section.
- moved the information about RealD’s relationship with Sony to the RealD inc. article where it seems to belong.
- edited the text that was left so that it sounded less like boasting.
- Only the note about its affordability and the following sentence which was deemed unnecessary for this article, was removed. “It requires only one projector, unlike older film-based stereoscopic 3D projection technology.”
As I just did a revert of a Sony employee a while back. I was thinking that it would be handy to have an all purpose section on this talk page that could be linked to from the edit summary when performing such a revert. The section would explain Wikipedia’s position and, while noting that their contributions are of course welcome, ask them to please explain the reason for their changes on the talk page.
I’ve created a ruff draft of the possible referral section below. I’d welcome any feedback on it as I’m hoping that others who wish to stem the tide of self-serving promotional edits on this article will feel comfortable linking to it as well.
The reason your edit was reverted (Initial draft)
This Wikipedia article has been the target of self promotional edits by employees connected to the RealD brand name. While employee contributions, especially those of technicians and others in non-sales like positions, have proven valuable for reasons of accuracy and so forth, your edit has been reverted because one or more of your changes, at first glance, seemed to be of a self-serving promotional type nature. As you might suspect, this behavior is frowned upon in Wikipedia. Please refer to this link for more guidance regarding self-promotion. If you do decide to undo the revert or modify your contribution, it is desired that you create a new section which explains your thinking. Note: It may only have been one of several changes which you made that seems suspect, but unfortunately it is a very time consuming process to sort out the good from the bad in situations like this and so it is preferred that you do this yourself.
Is it possible to get some pictures of a Z Screen and put them in the article? That would be good, so that people can see what a Z Screen looks like. --Klltr (talk) 06:57, 14 December 2010 (UTC)[reply]
This technique can't be used for direct-view televisions or monitors because they're incapable of emitting polarized light. It could be done using an old-style front projection television system because it'd be the same as the theater system, but smaller. It might also be possible to make it work with a rear projection TV, as long as the back projection screen doesn't foul up the polarization. A direct view flatscreen TV would need switchable polarization filters on every pixel instead of just the one at the projector. That would increase the cost of the TV but would eliminate all the disadvantages of shutter glasses. They're heavy, require batteries or power cords, the wearer has to keep the head level, they interfere with viewing other LCD screens and they're expensive. The polarized 3D glasses need no power, they're no heavier than cheap sunglasses, they're inexpensive, the wearer doesn't have to keep the head level and the glasses don't interfere with viewing other stuff, though the bag they're sealed in has a warning they're not safe for use as sunglasses. Bizzybody (talk) 08:05, 27 December 2010 (UTC)[reply]
After seeing TRON: Legacy, I'm pretty certain Disney's Captain E.O. show used this or a similar polarization system. The glasses were pink and didn't fold, and they had attendants to take the glasses back, but aside from that I recall the effect was much the same back in 1986 for Captain E.O. as it 2010 for TRON. It's like a full motion video ViewMaster, especially the trailer for the 4th Pirates of the Caribbean movie. Bizzybody (talk) 08:09, 27 December 2010 (UTC)[reply]
This Wikipedia article has been the target of self promotional edits by employees connected to the RealD brand name. While employee contributions, especially those of technicians and others in non-sales like positions, have proven valuable for reasons of accuracy and so forth, your edit has been reverted because one or more of your changes, at first glance, seemed to be of a self-serving promotional nature. As you might suspect, this behavior is frowned upon in Wikipedia. Please refer to this link for more guidance regarding self-promotion. If you do decide to undo the revert or modify your contribution, it is desired that you create a new section which explains your thinking. Note: It may only have been one of several changes which you made that seems suspect, but unfortunately it is a very time consuming process to sort out the good from the bad in situations like this and so it is preferred that you do this yourself.
The above is a general purpose section intended to be linked to when reverting potentially self-serving promotional type edits.Dave3457 (talk) 12:12, 8 January 2011 (UTC)[reply]
Could someone please link to a video of a lecture or documentation where it is explained in detail of how the system with circular polarized light works?--92.228.204.34 (talk) 18:57, 10 August 2011 (UTC)[reply]
I would recommend reading the lead and first section called General description in the Circular_polarization WP article and then following the suggested link to circular polarizer section. As it happens I've written both for people almost exactly like you and would be very appreciative of any feedback you might take the time to give me on my talk page. Of course you should already know about Stereoscopy. That being said, I'm not sure that's the kind of "detail" you are looking for. Dave3457 (talk) 20:32, 10 August 2011 (UTC)[reply]
Sony Reald and ZScreen used on dlp projectors have been I belive confused in the article. Sony projectors can't project in 48fps so they project a split screen image with two 2k images in 24fps that are then projected trough a special lens. So the following statement from the article The single projector solution also results in a halving of horizontal resolution is true but only for sony projectors. On DLP projectors a ZScreen is used to divide 48fps to 24fps per eye instead which is explained in the article but it doesn't mention that ZScreen is not used on sony projectors. — Preceding unsigned comment added by 80.221.45.135 (talk) 16:06, 15 September 2011 (UTC)[reply]
Thanks, I removed the claim. It wasn't properly referenced. Better safe than sorry. I copied it below in case anyone wants to re-include it with a reference.
The single projector solution also results in a halving of horizontal resolution. For example, Sony's 4K SXRD imaging device, which projects a 4K 2D image, will produce a 2K-per-eye 3D image.[1]
I removed the first sentence in the technology section because it was apparently out of context, referred to a photo that doesn't seem to exist, and was just generally unclear as to what it was talking about; now the first paragraph in that section actually starts to introduce the technology where before it just seemed to jump into the middle of an explanation that was missing a beginning.
I'm just pasting what I removed here in case someone knows more about what it meant and wants to fix it:
Looking into a mirror with just one eye will cause the lens over the open eye to appear darkly tinted in the reflection. In this photo[which?], a mirror is between the background and foreground images of the glasses.