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back to article The terrifying tech behind this summer's zombie assault

So there you are in the cinema. Watching Titanic again for some reason. Kate Winslet has just saucily suggested to Leonardo Di Caprio that he paints her like one of his French girls. Then she leans over and pokes you in the eye. What happened there? You’ve got a fair idea how 3D films are made, and you’re pretty confident that …

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Sigh...

There's a damn good reason stereoscopic imagery is so painful for many people: we evolved (in all likelihood) from something that survived because it was capable of noticing the twitching tail of that tiger, and very quickly tracking it and focussing on it to decide whether it's going to bite us or not.

Until the 3-d directors (I'm looking at you, Cameron) can provide an image which is in focus at all depths, we're going to be stuck with moving elements on which the eye tries to track and focus and *can't*.

Eye tracking angle is only one of a list of cues the brain uses to position objects in space, and I'm not convinced it's even the most important one:

- relative size (this cow is small, but that cow is far away)

- absolute size (people are much the same size, so that smaller one must be further away; mountains are *huge* so if you can see it all it must be distant)

- relative colour (blue atmospheric haze, for example)

- occlusion (near objects hide far objects)

- similarity of view (seeing slightly different views of an object, and how different they are)

- focus

and of these it's probably focus that causes (literally) the most headaches. Stereoscopic projection requires that the eyes focus on the screen - effectively close to infinity, or at least the hyperfocal distance) while the tracking information insists that the object is nearer. Which is why it's less of a problem when the stereo field is beyond the screen, and why Cameron's floating thingies irritated all the way through the film.

In the 1890s, the 'American Pattern' stereograms were very popular, and they're still effective - largely I believe because the contact prints used had very good resolution. The image is at infinity (tilted lenses in the viewer) so every detail is sharp, wherever the viewer looks - and the main cue is the differing *view* rather than the eye tracking position.

But films have a grammar all of their own, and the directors pull the focus to guide the viewer's attention... and until that goes, we'll never get decent 3-d film.

The technology is fascinating, but the sooner this fad disappears for another twenty or thirty years, the better.

(http://stereo.nailed-barnacle.co.uk/#!album-10 for Victorian 3-d technology explained; http://stereo.nailed-barnacle.co.uk/#!album-0 for some American Pattern scanned images; http://stereo.nailed-barnacle.co.uk/#!album-9 for the same images a red-cyan anaglyphs.)

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Re: Sigh...

Slightly OT (though not entirely as 3D is in a number of new games these days), but focus issues irritate me in video games too, they're rendering everything in focus, then hiding stuff behind a depth-of-focus filter, and your eyes try to focus on these objects and fail. I'd rather put up with bad aliasing along edges than the supposed cinema-style depth-of-focus effects, you're not supposed to be playing a video game from behind a camera lens. (Don't get me started on bloom or lens flare...)

Luckily some PC games let you turn off depth-of-focus in graphics quality settings, but not all, and it's rarely an option on consoles.

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Boffin

Re: Sigh...

"Until the 3-d directors (I'm looking at you, Cameron) can provide an image which is in focus at all depths, we're going to be stuck with moving elements on which the eye tries to track and focus and *can't*."

Hits on a point about 3D that the article brazenly skips over - it's not all about eye position (or Columbo would have no idea about depth), but combines with visual cues and where your eye is focused. Similarly, if the picture was in focus at all depths, your eye would be baffled at switching relative position and *not* having to adjust focus.

This is pretty much the cause of people feeling nauseated and getting headaches.

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Re: Sigh...

But cant you see where this is in fact leading?

Multiple cameras at varying focal and physical positions capturing a scene where you don't even store it as a 'retinal image' of pixels, but bang it through some fast DSP stuff to construct an actual 3d rendered model of the scene 50 times a second, down to the last grass blade.

Or fractal representation thereof.

That is no worse than going from 2 track audio studio to a 48 track one, for example, and having the mixing done. Inverse ray tracing to decide not whatt point X looks like from point Y, but what the properties of point x are, given the points of view of positions A,B,C.D and E etc.

You now HAVE enough 3D info to reconstruct the scene from pretty much any angle over a fairly broad area.

The trick will be to actually somehow project that so that by leaning to the left you CAN see round the foreground objects and you DO have to refocus to capture different parts of the scene. That might mean one micro lens per thousand pixels..projecting a virtual image to a point in the auditorium..exept where that image would be blocked..by an object in front..

easier to do on a personal basis with 3D glasses of course.

Its all doable FSVO speed and hardware and computing power. And cash.

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Re: Sigh...

[4 Neil Barnes] Spot on with your comments about depth of field.

I was taken to see the "new" 3D re-rendering of Jurassic Park and though the 3D was stunning when it worked the immediate thing I noticed was that so much of the frame was out of focus.

This, of course, because the original 2D movie was made with standard compositional knowledge and practice built over nearly a century of making films: shoot the things you want people to look at in sharp focus and use depth of field to blur the unimportant stuff. Creatively increasing the depth of field mid-shot is also a boffo way of causing the viewer to understand that the POV character has just become aware of something, often something behind him/her (these days it is usually something that looks like it was sneezed out of Godzilla's nose that has dozens of sharp teeth and claws).

Unfortunately, the large amounts of blurry background that made up the majority of Jurassic Park were jarring in the 3D version, making for a partial fail.

What worked well (and worked well in Despicable Me 2 in which the makers showed admirable restraint until the credits) was the lack of forward-projecting imagery, which meant such imagery wouldn't get truncated abruptly at the screen edge causing a sharp dislocation in the viewer's perception of the action. Avatar suffered from this in spades.

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Butchering a film and paying more for the privilege

Most live action 3D films are just a 2D film going through the computer equivalent of vacuum forming. Someone produces a 3D model which corresponds to the scene in the 2D image and then drapes the image over the top of it to produce a depth map and then shoots left and right eye offsets of it. Then to compensate for the reduced light levels of polarized glasses they jack up the colours.

I'm sure the process has improved from the atrocious cutout dioramas of earlier films but IMO it's still akin to colourizing black and white - no matter how good it looks it still won't look as good as filming it in colour in the first place.

3D works best when it's filmed or rendered in 3D in the first instance. It also helps if the movie doesn't suffer rapid field of view / focus changes which induce the headaches. Keep it subtle and avoid stupid gimmicks (e.g. things flying at the audience)

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Blender

A few parallella boards and some imagination.

And a headset that recognises your head position. 3D will never catch on until you can sit in whatever position you want and get a proper 3D effect.

It is likely to be achieved by watching an animated computer model through a rendering engine rather than a rendered image that is fit for only one viewing position. This would reduce the data rate required too! Most US films could be compresses to about 2k of script and a few images (a flag) to wrap around the hero.

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It is all very clever, but the experience is still painful to be enjoyable. I'm holding out for proper 3D as depicted in "The Flipside of Dominick Hyde" (for thos of you with long memories).

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Now that brings back some memories!

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"3D films are increasingly becoming the standard"

No, they're not. That is a fad that is already starting to fade because

1) people are annoyed by the surcharge

2) people get headaches

3) people are wisening up to the fact that today's 3D is just glitter, bringing nothing to the plot

Historically speaking, we first had black & white films without sound. They were perfectly capable of telling a story. We added sound to the black and white films, and were capable of telling better stories. We then added color to the films, and the stories we told became more natural.

At no point did anyone point at the screen and laugh and say "it's all 2D !". Nobody cared. Immersion was sufficient.

Now the media industry is desperately trying to add 3D and make people believe that it is important, indeed, revolutionary. Except 3D does nothing to improve the telling of a story. On the contrary, it clashes with immersion, and most often jarringly brings home the fact that you are watching a film.

There may be a time coming when some genius filmmaker will find a way to make 3D relevant to the story - miracles can happen. At this point in time, all 3D is used for is the same trick as the very first black & white film that showed people a train coming head-on - and people fled from the theater.

That trick is old now, and people are getting tired of it already. I cannot count the times I've already heard friends and acquaintances talking about the latest film they saw in 3D and mentioning that the 3D was annoying more than anything else. I've had some friends state that they will no longer go to a 3D viewing at all. I know I won't.

So no, 3D is NOT on its way to becoming a standard.

Not by a long shot.

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Re: "3D films are increasingly becoming the standard"

Very true I've only been to one 3D film which was Prometheus and I'm not doing that ever again.

If nobody goes to see them at the theatres the studios might be hopeful of watch-at-home sales but 1.6TB per movie isn't going to make that easy.

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FAIL

Re: "3D films are increasingly becoming the standard"

I'm with you and Kermode on that one (2011 - http://www.theguardian.com/commentisfree/2010/apr/11/3d-avatar-hollywood)

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Trollface

Re: "3D films are increasingly becoming the standard"

> not doing that again

But was it "Prometheus" or the "3D" that did it?

Imma drinking my black oil now, thanks.

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Mushroom

Re: "3D films are increasingly becoming the standard"

and the BBC has indefinitely suspended any 3D broadcasts meanwhile 3D-TVs are stockpiled in the warehouses.

Yep... some standard.

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Great read

I find all this stuff fascinating, more plz.

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Rotoscoping

and no mention of the ring wraiths in the animated "Lord of the Rings" of the 70s ?

I recall at the time being very spooked by them ... such lifelike movement in a cartoon.

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Re: Rotoscoping

If I recall, by the end of the film it was actually most of the orcs, etc. too. Started to get a bit off-putting as I felt the movements were too realistic espcially in comparison next to the clearly still animated main characters. At the time I heard that doing the "crowd scenes" this way was cheaper as there were some financial difficulties (hence no part 2, etc.). Hiring a bunch of people to dress up a bit and run around some fields waving swords then hiring people who can trace over them is presumably cheaper than hiring a sufficient number of qualified animators.

Surprised that A Scanner Darkly didn't get mentioned in the context of rotoscoping. Whatever you thought of the story (or of Keanu!) I found it quite captivating the way that things appeared to become clearer even as they moved away and moved out of focus. Not sure I'd want every film to be like that but it worked for me in that film.

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Hmmmm

An article on 3D or a freebie advert for Sohonet?

I can't quite grasp the need for that 3rd page.......

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Anonymous Coward

Not All 3D Vision comes from Stereopsis

I remember reading in Simon Ings book, The Eye, that stereopsis only provides 3d vision for objects relatively close up. For objects at a distance, depth perception mainly comes from moving the head from side to side. Taking two offset pictures is never going to be able to replicate this.

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Re: Not All 3D Vision comes from Stereopsis

For most people, there are two forms of stereo vision; the objective and the subjective. The second is rarely discussed because it is , well, subjective, and hard to quantitize, and impossible to mass produce.

Objective: what eveyone is taught that stereo vision is, two images from different angles that are combined to form a 3D image. Almost everything with two eyes uses this.

Subjective: It is rare that both eyes focus equally. usually each eye has a different focus. for example, one eye can be 20/20 and the other 20/35, or any other combination.

The individual's brain then compares the difference in focus, and uses that along with the objective method to generate a 3D image of the enviroment. The advantage is that it enables a deeper field of 3D than objective stereo vision.

Most people don't realize that they use the subjective method because they've never heard of it, and really it doesn't matter until you try to watch a "3D" movie.

Then the brain borks out because the objective version is telling it one thing, and since the two frames are at a set distance and focused equally, the subjective is telling the brain something entirely different.

The result? Headaches, eyestrain, even nausea.

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How its called 3d is beyond me

At best its 2 and 1/2 D . Can you walk around it ? Nope. Can you look at it from above and below ? Nope . Just every now and then you get depth perception in one plane , and even then you have to wear special glasses . Fine if you dont already wear glasses but a pain if your a speccy like me . I was enthusiastic when the latest wave of 3D started but I have seen too many turkeys where the emphasis was style over substance. I generally opt for the 2D version .

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That Eye Poking

> Then she leans over and pokes you in the eye.

With what, exactly?

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Re: That Eye Poking

no idea... but at least she was poking you in the eye....

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Bandwidth

Why are these guys moving all the data around? Why not have one big datacentre and have everyone log in via VDI. The cost if 10gb/s connections is high and would support 10,000s of VDI connection. Typically only high frequency traders can justify international 10gb/s connections and they max them out 24/7. I bet these pipe are empty most of the time.

When you actually need to move the finished product around, send a person on a plane with hard disks - cheaper and probably as quick.

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Re: Bandwidth

simple answer. Computing power and bus bandwidth.

Actually working the data on and off the disks is already slow on a workstation, saharing the bandwidth from CPU to disk with other users would be intlolerable

Its the same reason its faster for me to download a graphic object from my server and edit it locally, then upload it, that try and edit it in place.

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Found a good 3D film

I'm totally against 3D films and whenever I take the wife to a film we always pick the 2D version .

I've seen about 6 films in 3D, largely because we used to live in a small town with only a 2 screen cinema and if you didnt grab some films in 3D then you had to wait and risk not seeing it until you got it on DVD.

Then we saw Dredd and , frankly it worked. The 3D actually added to the film, due to what they were trying to show. But even that was 3D or nothing, we couldnt find a 2D showing that weekend.

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Re: Found a good 3D film

I've seen a few where it worked, but it worked in the way that it only made the film more immersive, so I can't actually remember which films...

I can't stand it where they've clearly designed a scene to show that they have 3D - the natives chasing Kirk in the latest Star Trek, for instance.

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Local Cinema

Our local 2nd run cinema has options for 2d and 3d. Seeing how most people prefer 2d, most of their showing are in 2d.

The explanation by Rajat Roy explained it well, but he seems to think we are philistines because we expect 3d, and not their artistic interpretation. I do hope this is a fad and it goes away.

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@Gavin Park Weir

You are so cute when you are clueless. ;)

At my shop we have a 10gb/sec connection just for our corp traffic. Our dedicated backnet is also 10gb/sec, strictly for our operations traffic. Our front end is 30bg/sec if I am not mistaken. We aren't traders, just a SAaS business with average bandwidth needs. It is pretty common...

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Save the planet: stop the Hollywood movie machine!!

Hollywood is killing us all! Given the specs and usage described on page two and HP's own carbon footprint calculator, one production can produce almost 96,000 tons of carbon. And that doesn't take into account actual production during filming, food, transportation, networking, climate control in offices, and so on (see "I, Pencil.") With all the bombs produced this summer, it seems like we could put Global Climate Warming Change into a tail-spin by simply stopping, or at least putting the brakes on, Hollywood's incessant production of crap.

Sure, some people like that "crap," but there are bigger, more important things about which we must be concerned.

Call your MP, Congressman, EMP, whomever, and tell the to stop the Hollywood-industrial climate-killing machine, now, before there's still time!!

Paris, TOO LATE!

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Re: Save the planet: stop the Hollywood movie machine!!

Really? Anyone care to calculate the carbon footprint of the server farms currently hosting pictures of cats or moving peoples 140 character blither around the world?

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Astronomical storage requirement.

" Given that there are 24 such frames every second, you’re looking at an astronomical storage requirement: 288MB per second, 17.3GB per minute. Or 1.6TB for a 90-minute movie. "

1.6TB is not "an astronomical storage requirement".

Cheap SATA disks are areound 4TB last I looked.

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Re: Astronomical storage requirement.

Agreed, those numbers may not be trivial, but are workable with just-above-mainstream tech. Adding in versioning and all footage cut from the final edit will jack up the numbers significantly (and remember movies are often too long, at 2+hours, not 90 mins), but again, not crazy for a big-budget movie. 24 FPS is far too low, though. We need at least 48 FPS, which doubles the numbers.

The oil and gas industry probably laughs at these numbers.

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Two Things

1) The relative placement in our two eyes is only a small portion of how we perceive depth. This placement being out of whack with the many other factors is part of why 3D movies cause problems for something like half the population.

2) Are we really still pimping 3D tech? Shouldn't this article be about 4K or 48fps?

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Avatar

I really wanted to see Avatar because of the way James Cameron wanted to push forward the technology of cinema (and because I liked Abyss), but then I heard the plot revolved around a substance called Unobtanium and I vowed never to watch it. I had a near miss on New Year's Eve when some friends wanted to watch it, but thankfully sense prevailed and we watched Beethoven instead.

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