One of the earliest forms of stereoscopy that didn’t involve lenses, mirrors or crossed eyes (or looking at an actual 3D object) is the “anaglyph” approach, wherein colored filters are placed over the eyes in order to mask the portion of the image intended for the other eye. This works because human retinal cells are sensitive to red, green and blue, where other colors are some combination of those (yellow is red + green, etc.).
Additional 3D viewing technologies exist out there as well. There’s active shutter, which mechanically blocks one eye’s view at a time, very rapidly, and the display actually switches between the two eyes in sequence with perfect timing to the glasses. There’s the popular use of polarization that utilizes polarized filters’ ability to passively block polarized light, allowing for display of unaltered full-color images to each eye. And then of course there’s 3D displays like the one in the 3DS, where different images are visible depending on the viewing angle.
Of all the stereoscopic options out there, anaglyph continues to be one of the most successful–despite its intrinsic loss of color precision–for a very simple reason: it always works. Polarized glasses won’t work without a polarized image to look at. Shutter glasses won’t work without a rapidly-changing image. 3D displays are, well, displays, in addition to being hard to find and/or expensive. Anaglyph works with any display that can split color channels, and even works in printed material. It’s by far the most accessible, and therefore the most successful.
Anaglyph can use any combination of primary colors, but most commonly uses red for the left eye and cyan for the right eye. In the past, it was red and blue, or in some regions red and green. Red and cyan is preferred because it lets the most color information through to the eyes. Personally, I prefer magenta/green due to the way the eyes perceive relative brightness of the three primary colors, but when’s the last time you saw a pair of magenta/green anaglyph glasses? I’ve got a pair on order from Amazon, but they’re not very common.
I also ordered a pair of TriOviz Inficolor 3D glasses. These are touted as some fancy-pants highly-engineered special filters for true-color 3D gameplay. But the fact that they work with standard-issue displays tells me that they’re just glorified magenta/green glasses with some software processing to detect aligned image elements. I’ll have more information after they’re delivered tomorrow.
There’s a variation on anaglyph out there called Anachrome, but it’s hard to find information on it and I can’t cite any good sources because of that. I believe it was around 2002 when it became a thing. One of the “problems” it addresses is that photographic red/cyan anaglyphs can be disorienting because some subjects–like human lips–wind up being eliminated from one eye entirely and the brain can’t align the images very well in all contexts. The other “problem” was that a typical anaglyph prevents true-color perception as an artifact of how it works. As my sarcastic quotation marks probably gave away, the “solutions” to these “problems” caused some actual problems of their own…
Anachrome dictates that each colored filter lets through a small percentage of the image intended for the other eye. This gives the brain cues of how to align images when a color would otherwise be absent from one of the eyes. By extension, this also improves the color perception of the image because both eyes see at least some amount of all of the color in the original image. A byproduct of this approach of course necessitates that there be a smaller degree of stereo separation in the image, or else the other eye’s image would visibly overlap during viewing. On the other hand, less separation means a closer representation of the original colors when viewed without glasses, so Anachrome is a very appealing thing in context.
So what’s the problem? It’s the solution, of course: Anachrome glasses let through light intended for the other eye. When trying to view Virtual Boy images on a 2D display, this simply doesn’t work well. But since the 3D movie fad from a few years back raised such a demand for glasses that operate this way, it’s pretty much impossible to get a pair of true anaglyph glasses anymore. How’s a body supposed to emulate Virtual Boy now? )-:
A better way?
How can we view Virtual Boy images on a 2D display if 3D glasses don’t do the trick this day and age? Obviously the answer is to find a pair of actual-anaglyph 3D glasses, but where to look? I had three ideas, so I bought three kinds of 3D glasses to give it a go. The following links are to the exact products I purchased:
Infiview 3D – Even if this is just a glorified pair of anaglyph glasses, I’ve seen a ton of people give a ton of positive feedback on it. I’m sold on the idea that it works well, and I’d love to get my analytical eyeballs behind it so I can figure out what makes it tick. And who knows, maybe it really is the new best 3D viewer?
Magenta/Green – This exact pair is obviously of the “box of Cracker Jacks” variety intended for B-list movies, but I went for it in hopes that the magenta/green combination dodged the Anachrome bullet. Even if the glasses suck, they just might due a proper job of separating the light that reaches each eye, which would give it a big advantage over typical red/cyan pairs.
“No Ghosting” Red/Cyan – The way one image bleeds into the incorrect eye is referred to as “ghosting”. This was the only pair of red/cyan glasses I could find that claimed to have no ghosting. It actually looks like it’s a pretty solid design; I just hope the filters live up to the claim.
These will likely arrive in the order I’ve listed them, with the Infiview glasses coming tomorrow. As they come in, I’ll post replies to this thread with my findings and (if any) recommendations.
Anyone else have experience with finding the right 3D glasses? Which ones did you choose?
I simply use Mednafen in side-by-side mode and relax my eyes. Don’t need any fancy glasses. If for some reason I did, I’d use my Oculus Rift or Gear VR. 🙂
The TriOviz Inficolor 3D spec is clearly using the same approach as Anachrome. It uses green and magenta to help the eyes equalize perceived brightness, and lets through a crazy amount of all three primary colors through both filters. Games designed for use with it require such an infinitesimal separation between the eyes that it can be hard to tell that an image is even 3D at all. I don’t recommend it.
The run-of-the-mill green/magenta are showing a typical amount of ghosting like I’ve seen in red/cyan glasses. They’re pretty good, and no doubt work great with movies, but still visually jarring when looking at Virtual Boy renders.
Here’s hoping the “no ghosting” glasses are actually that. Of course, they have to ship them out before that can happen, and the order is still “Processing…”
Although I have an ASUS VG23AH passive 3D monitor, I’m still interested in the outcome of this thread. There are obviously many more 2D displays in the world than there are 3D-capable ones, and anaglyph is a good balance of trade-offs for displaying 3D on them (especially Green/Magenta, with its better luminance balance and lossy compression tolerance).
I still have a few pairs of anaglyph glasses I break out once in a while for the odd anaglyph-only website. One tech you seem to have left out of your roundup is the “Intru3D” amber/blue glasses cross-promoted by Intel and Dreamworks back when “Monsters vs. Aliens” came out. As usual, there’s a license fee associated with the “color preserving” part of the technology, but they also work fairly well with straight yellow/blue anaglyphs.
EDIT: Wait, I kinda got mixed up there… The InTru3D stuff is rendering technology, the paper glasses used for the Super Bowl ads was called “ColorCode 3D”. US pat. 6,687,003
Still hoping those “no ghosting” glasses do the trick. If they do, I sure as heck wouldn’t recommend paying extra for expedited shipping from Light in the Box. They said processing would be 1-4 business days, I bought it on February 15, and they’re estimating it will be shipped on March 1.
Let’s see if it’s worth the wait. (-:
So it took 11 days to process my 1-4 day processing order. On the other hand, DHL managed to get it here from China in three days over the weekend, so there’s that.
Putting on these no-ghosting 3D glasses and covering my left eye while looking at red things, they’re very visibly red. Like, not a tad red where I can make out what color they are, but rather a red object with a cyanish tint. The net effect when looking at an anaglyph? Ghosting.
bmo registered an account with Light in the Box because he was interested in buying some no-ghosting glasses, but wanted my feedback first. Even after unsubscribing from their e-mails, they continue to spam him. So the site earns the trifecta of poor customer service: unsolicited advertising, missed due dates and products that don’t match their descriptions.
Soooo, I’m still without a pair of anaglyph glasses that is capable of reducing ghosting to a negligible amount. I’m most pleased with these generic green/magenta ones, though. I think I’ll stick with them when I have the option of choosing which colors to look at.