Editor's Note: Each Friday, High-Def Digest's own HD Advisor will answer a new round of questions from our readers. If you have home theater questions you need answered, send an email to HDanswers@gmail.com.
Answers by Joshua Zyber
Before we start this week, I felt it worth pointing out that I've recently made the editorial decision to use the spelling "3D" (no hyphen) when referring to three-dimensional cinema, rather than my previous preference for "3-D." For more on why I made this change, see this blog post.
Passive vs. Active Shutter 3D
Q: With the different offerings of 3D sets out there (passive and active shutter), will any 3D Blu-ray I buy work properly on either set? Could something change with current or upcoming TV technology that will not allow current 3D disc offerings to play properly?
A: The short answer here is yes. Blu-ray 3D will work with both types of 3D HDTV: those that require active shutter glasses or those that use passive glasses. The Blu-ray 3D signal is transmitted to either type of television as "packed" frames at a resolution of 1920x2205 (that's two 1080p pictures stacked one above the other). It's then up to the TV to separate out the left and right images and display them by whatever method the manufacturer has chosen.
TVs that use active shutter glasses will display each eye's view in an alternating series: left, right, left, right, etc. The shutter glasses will sync to the TV signal and only allow the appropriate image to hit the intended eye. On the other hand, televisions of the passive type will display both the left and right eye views simultaneously with polarized light. Some will display them side-by-side, while other may use top-to-bottom or a "checkerboard" pattern. The glasses you wear have polarized lenses that redirect the light to the designated eyes.
At the present time, the only way to get full 1080p imagery from both left and right eye views is to use a display with active shutter glasses. The passive displays, by necessity, reduce the resolution of each eye view in order to fit both into the same 1920x1080 pixel grid at the same time. In the future (perhaps even the near future), we may see higher resolution displays that have enough extra pixels to accommodate two full 1080p images side-by-side, but right now you'll have to compromise.
Q: I am in the market for a 3D Blu-ray player. I have as my TV the Panasonic Viera TC-P50VT25. I also received Panasonic 3D glasses that came with the TV. Does this mean I have to get a Panasonic 3D Blu-ray player to watch 3D movies? I was looking to purchase the OPPO BDP-95. Is this 3d player compatible?
A: You do not need to buy the same brand of Blu-ray player as your TV. Any Blu-ray 3D player will send the exact same signal to your 3D TV. The Blu-ray 3D spec requires universal compatibility in this regard.
The 3D glasses you wear are a different story. In most cases, you must use glasses that are specifically designed to sync with your TV. Toshiba glasses will probably not work with a Panasonic HDTV, for example. However, some companies have marketed universal 3D glasses that will work across all brands. XpanD is currently the leader in this product category.
Blu-ray 3D Backwards Compatibility
Q: When the Blu-ray 3D spec was announced, 3D discs were meant to be backwards compatible with 2D Blu-ray players and equipment. However, with the majority of 3D discs, this is not the case. Separate 2D Blu-rays discs are usually included instead. Why is this? Is it down to compatibility issues with older players, or because of space constraints trying to fit a 3D picture, lossless soundtrack and extra features on a 50GB disc?
A: A little over a month ago, I wrote up a blog post with the complete list of Blu-ray 3D titles available through the end of January of this year. (I'll try to update it with newer titles when I get a chance.) The list includes stats on whether and how each title is backwards compatible with 2D equipment.
Of the 38 titles available, 23 of them are compatible with both 3D and 2D on the same disc. (One of these also includes a separate 2D disc anyway.) 7 titles achieve backwards compatibility only through the inclusion of a separate 2D disc. 2 titles have no compatibility with 2D at all, and 6 are still to be determined. So, it would seem that the most popular option is to include both 3D and 2D on the same disc.
Those titles that require a separate 2D disc of course beg the question: Why? At least theoretically, this shouldn't be a disc storage space issue. A 3D image is created by displaying separate left eye and right eye views, each from a slightly different angle. To convert a 3D image to 2D, all the disc player has to do is turn off or ignore one of the views. The 2D version of the movie is already fully contained within the 3D version. It doesn't require a separate encode or more disc space.
It's possible that some studios have had trouble authoring discs that will play properly on all existing 2D-only players without compatibility issues, and so have elected to split the 3D and 2D versions to separate discs. Another possibility might be that this is simply a marketing decision. Keeping the versions separate helps to avoid consumer confusion about how to access each. It also gives studios an excuse to charge more if there are more discs in the case.
In almost all cases, the studios are going to author and release 2D-only copies of the movie anyway, so it could even be that this is simply a matter of laziness; they don't want to go to the effort or expense of programming and testing the 3D disc for 2D compatibility, and just decide to throw an already-existing 2D disc in the same case instead.
Is Anaglyph 3D Dead?
Q: I had a question regarding Blu-ray 3D. I think it's cool that they've been able to develop real 3D with fancy new TVs and such. But let's be honest, this is still a new technology and it's rather expensive for the average person (like me). I've noticed that ever since real Blu-ray 3D has been becoming more popular, 3D movies are being released in this new format and they're no longer releasing the cheesy red/blue 3D. Sure those cardboard glasses are kind of corny and the 3D doesn't look fantastic, but I really like it. Do you think they'll ever release any Blu-rays in this way anymore now that real 3D Blu-ray is becoming more popular? I like watching my 'Friday the 13th Part 3' and 'My Bloody Valentine' in corny red & blue 3D. I'd still like to watch other titles like 'Piranha' that way without having to spend $3,000 dollars.
A: The old form of 3D that required colored cardboard glasses (usually red & blue, though other color combinations have also been used) was called "anaglyph." With the advent of the new Blu-ray 3D format, I'd say that there's very little call for anaglyph anymore, other than for nostalgic reasons. I'm sure even you'd have to admit that it looks pretty crappy.
The advantages to anaglyph 3D are that it's compatible with any color television at all (no fancy equipment required) and it's cheap. I know of at least one upcoming Blu-ray title that will use anaglyph 3D: 'Scar 3D'. For the most part, however, it's going extinct – at least on Blu-ray.
If you watch Blu-rays on your computer, PowerDVD 10 has the ability to convert movies to anaglyph 3D.
The HD Advisor knows many things, but he doesn't know everything. Some questions are best answered with a consensus of opinions from our readers. If you can help to answer the following question, please post your response in our forum thread linked at the end of this article. Your advice and opinions matter too!
Blu-ray 3D Rentals
Q: I am trapped in an IFITL neighborhood that gets a maximum 1.5mbps connection, making HD streaming via Netflix/PSN/XBL/iTunes impossible. HD downloads take forever but are an option. Thankfully, I get Blu-ray discs via mail from both Netflix and Blockbuster. But we recently purchased a 3D TV and would like to watch some movies in 3D. Are there currently any services that either have 3D discs or 3D downloads (non streaming)? Or any services in the pipeline that may offer this service for people stuck in low-speed broadband areas? Buying 3D Blu-Rays are expensive!
Check back soon for another round of answers. Keep those questions coming.
Joshua Zyber's opinions are his own and do not necessarily reflect those of this site, its owners or employees.