Basics: What Is Stereopsis?

The two eyes converge on the object of attention.

Dolphins love that humans can view them in 3-D

In Prain Engrish: The ability to view the world with two eyes pointing at the same subject.

Some animals use their two eyes to look at completely different things simultaneously [chameleons]. Some simply look around to get one eye to focus [deer, horses, and cows come to mind]. Predators such as wolves, lions, tigers, and bears [oh my], consistently use both eyes to calculate the distance from their current position to their prey. Humans are awesome, the proverbial freaking bees’ knees, so we have this ability too.


From the The 3-D Rebel’s Guide:

A shot is fusible if an audience member can merge the left and right eye streams in his brain. This is the point of 3-D production.

A shot is, or parts of it can become, infusible if the net separation is too wide. So, fusibility is not just how far you push stereo separation of the foreground or background separately, but how big the separation difference is between foreground and background together. In Prain Engrish again?



You can pop 3-D way out forward, or push it way out back, but you can’t do both at the same time in the same shot, unless you want people to leave the theater screaming, eyes bleeding as their heads catch on fire and explode.

There is a delicate balance for keeping your footage fusible, and this is probably the stickiest wicket in the 3-D game. Use your storyboards to plan for extreme pop or push, the big gimmicks of 3-D, if you must use them.

You can place an optical barrier plane in your shot like a door, a wall, a giant robot, or a clear blue sky. Or you can change your mind about having to pop the snot out of this particular sequence.

Remember those conversations that start with “Wouldn’t it be cool if-” that I warned you about? Well, you’ve now been doubly warned: If your shot isn’t fusible, there’s nothing remotely cool about it.

– -=Seth Estrada

Good 3-D, Bad 3-D

Real D glasses

Image via Wikipedia

What Makes A 3-D Film “Good”?

Great question! A number of things will increase the likelihood that audiences will enjoy your 3-D movie or short film. Here are a few influencing factors:

Pre-existing storytelling elements unaffected by 3-D

Story, story, story! If your audience already doesn’t care about the characters, locations, objects of interest, situations, acts, or themes of a 2D movie, will giving that movie the 3-D treatment somehow change it’s mind? Not. Bloody. Likely.

Implementation of 3-D:

So there are many ways to carry out 3-D, some of them great and forward-thinking, some very middle-of-the-road, while yet others are not-so-great and completely bass-ackwards. Here, in simple terms, are the only 3 ways to carry out 3-D so that you are warmly received by a discerning audience:

1. It’s innovative and groundbreaking, 3-D like no one has ever actually seen before [not just a marketing line, but genuinely so] For example:

you’re crossing the line, a 2D cinematic transgression, á lá 24 or Bourne Trilogy, but the entire audience forgives you because the action is so compelling that they are completely oriented anyway, from being riveted to your character’s every move; you’re playing with lateral movement and depth cues at a dizzying rate, but you still have clear narrative flow just behind each occlusion, á lá Speed Racer; or you’re jumping back and forth between ‘card-boarding’ [very flat, ‘cold’ 3-D] to maximum parallax [very voluminous, voluptuous 3-D] in the same scene, but it plays into the emotional/psychological implications of the character arc or narrative.

In each case you are innovating in 3-D, twisting and bending the rules, provided you are aware of them, and calculating a desired effect beforehand. So you can be a master and flex your 3-D muscles, or you can go a little less all-out and just be sure that, at any rate,

2. It’s transparent and seamlessly ‘immersive’,

Meaning that the 3-D draws no undue attention to itself, but feels at all times totally natural and unobtrusive. So no dizzying camera moves, depth cues, or brain-stretching parallax montage. The beauty of Avatar was that it mostly employed simple Mise en Scene [thoughtful staging of events in front of the camera]… but in 3-D. Last but not least if you are resolved to the fact that you’re no James Cameron be sure that, at least,

3. It’s at least not vomit-inducing [Do no harm, as Lenny Lipton would say].

Be able to understand at least when you’ve gone so far that your audience’s brains literally cannot ‘fuse’ the two images together: If your audience pukes when it’s not supposed to, you lose. Duh. However, you’d better have one hell of a narrative for the audience to overlook your total lack of skilled 3-D when you tack on a giant “in 3-D!!!” at the end of your movie/documentary/short film title!

The last ingredient is dumb luck – like every other 2D hit, of course.

Think of slightly more recent hits like Napoleon Dynamite and The Fast and The Furious… then think of Scott Pilgrim vs. The World. They all fared well on some level, but took very different routes to get there, and all completely unintentionally, and almost entirely dictated by luck.

What Makes A 3-D Movie/Short Film “Bad”?

See all the arguments above, flip them all into reverse, then add to it the shame of hyping up the garbage film by tacking on “in 3-D!” at the end of the title and talking it up like it’s the bees’ knees… That makes a 3-D film bad, mmkay? If you can’t ‘polish a turd’, as they say, with elbow grease, you certainly can’t polish it with baseless hype.

Of course, you will make an awesome film of exceptional value, both artistic and technical. But remember not to put the cart before the horse; 3-D is an important medium so use it, but don’t abuse it by making it self-important.

– -=Seth Estrada