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CGI verse models


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I helped build the model sets and shoot the following years ago;

 

 

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?version=3&feature=player_detailpage"><param name="allowFullScreen" value="true"><param name="allowScriptAccess" value="always"><embed src="
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I'm kind of curious, does anyone think it would look better today if done with CGI?

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Totally agree. I used to have discussions about how to emulate real world stuff during down time between takes. Eventually the conversation steered towards CGI. My friends were interns for Apple, and they were on the inside track of what was to come about (this was circa 1987). They were of the opinion that computers would do everything someday.

 

Where I believed that, I didn't think it a good thing. To me CGI looks like plastic. And now that it's gotten to be more expensive than shooting real actors/crowds/stunts, one wonders why it's used as often as it is.

 

I think CGI is excellent for smoke and water, but I prefer models or real actors for lots of other stuff.

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I'm currently working on a Dreamworks project - %100 1:1 scale animatronic creatures with pyro !

 

Zero CG apart from some projection effects

 

Pity its not a film dry.gif

Film - you know, I kind of shrug my shoulders at film verse digital. I mean, it's cheaper to store bits than to store film canisters, but every time I worked on a digital project the light's always organized differently. Like they said on another thread, you can get better diffusion with film than with chips.

 

One of the first thing eveybody noticed with digital cameras is the vertical light streaks shooting up and down the frame. You couldn't get regular diffused highlights anymore. I often wondered what our projects from the 80s and 90s would've looked like with digital cameras.

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Simply because I'm an unemployed former Stage Manager, AD, SFX assistant etc., and I like to name drop just to show I'm not a pathetic loser on this BBS by mining other peoples' past glories, even though I am :), I worked for the guys who did the following;

 

 

Would CGI have made this better?

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yip

 

but in saying that this sequence has a TRUCK LOAD of personal history wrapped around it for me...

 

Trying to watch it with fresh eyes I do note a bit of weird physics going on with the motion of the ships and a few slightly offset explosion and so on.

 

But then, you get that today even, so go figure ;)

Edited by Chris Millar
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I used to ask about filming that sequence, but the guy I used to work for would only take a drag on his cigarette, then throw it on the ground, and bitterly say "That f____ing thing." before walking off. Regardless of how difficult for him it might've seemed, it's a sterling piece of work.

 

To me CGI still looks like plastic animation. I saw the latest "John Carter" trailer about 20 minutes ago, and as impressive as the detail of art is, I think the motions and physics still make it look fake. With Jedi you accept that what you're looking at isn't real, but allow the action to sweep over you, convincing you it's real.

 

Just my take.

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Isn't that, strictly speaking, the version that CGI has made better?

 

A small proportion of of the original Star Wars trilogy had some pretty serious bluescreen extraction problems, especially in some of the pyro. The digital redo of all the compositing really did help in some cases.

 

Not that there's anything wrong with the original model work.

 

P

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Yeah, the travelling mattes really stood out in the original telecines for the home video market. Cleaning that up is a very effective use of digital technology. But the CGI models and motions, to me at least, look inferior to actual physical models.

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There's an interesting point regarding motion because the models used in that sequence were on motion control cranes that probably used very similar mathematics to produce interpolated motion as the computer programs that replace them. They also probably have far poorer lighting interaction with the surrounding objects, and of course there's the problem of adequately matting the whole thing together without leaving a big black outline around everything.

 

I think the only place the models really shine is in the surface textures, motion and lens effects, and lighting, which by definition are accurate to real world behaviour. There's always the danger of an enormous brush mark or glue line, of course, but computers are only now starting to become capable of rendering radiosity and other types of global illumniation (at least in reasonable time) that really gives things that last nudge into reality.

 

Certain things, like smoke, fire and other small particle effects, are still tricky.

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There's an interesting point regarding motion because the models used in that sequence were on motion control cranes that probably used very similar mathematics to produce interpolated motion as the computer programs that replace them. They also probably have far poorer lighting interaction with the surrounding objects, and of course there's the problem of adequately matting the whole thing together without leaving a big black outline around everything.

 

I think the only place the models really shine is in the surface textures, motion and lens effects, and lighting, which by definition are accurate to real world behaviour. There's always the danger of an enormous brush mark or glue line, of course, but computers are only now starting to become capable of rendering radiosity and other types of global illumniation (at least in reasonable time) that really gives things that last nudge into reality.

 

Certain things, like smoke, fire and other small particle effects, are still tricky.

I don't know what "radiosity" is, but it sounds like simulated sunlight; i.e. brightness and at what angle the rays hit the object.

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Radiosity is one of a group of terms used to refer to the lighting characteristics of a scene caused by light which is reflected from surfaces within the scene. A trivial example would be a red ball placed near a white wall and illuminated from above by a white light. Both the ball and the wall are illuminated and made visible by the light, but the red color of the ball will be visible as a reddish tint cast on the wall by light reflected by the ball, the intensity of that casting being proportional to the distance between them. Likewise, the side of the ball nearest the white wall will be more brightly illuminated because of white light reflected from the wall.

 

Needless to say, this effect is implicit in nature. 3D graphics software that is capable of simulating it is said to have a global illumination model, and the most accurate calculations can be done by treating a fine grid of points over the surface of all the surfaces in the scene as individual light sources, with their direction, colour and intensity based on the characteristics of the surface and the light that was already striking it. Even though most solutions ignore light that has gone more than three to five bounces off various objects, because it is too faint to matter by then, global illumination is time-consuming. A matt surface, for instance, is for this purpose one which is equally likely to bounce light off at any angle, which means that a very large number of virtual light rays must be calculated to adequately simulate the real world object. Usually techniques are applied to limit the number of rays to be calculated to the minimum required for an acceptable result, which generally means that the software will quickly produce a rather noisy, gritty image by randomly selecting rays to calculate. This solution is then refined by casting additional rays until some criteria for an acceptably noise-free image are met.

 

Even so, the technique is time-consuming, and it is by no means a foregone conclusion that all rendering for feature film effects would use it (at least right now). It is also less critical that global illumination is simulated in scenes where objects, or parts of objects, do not pass near one another, which arguably applies in cases such as the space battle we've been discussing, although that one in particular shows spacecraft in close proximity to a big grey space station which should properly be illuminating them to some extent - although it isn't, because they were probably shot as separate passes.

 

There are quicker ways to approximate some of the aspects of true global illumination, such as ambient occlusion, which darkens areas based only on their proximity to other objects - a digital version of painting darkness and grime into the crevices of a model. This technique, in one of its more rough and ready approximations, can even be fast enough for realtime rendering, and has been used in computer games.

 

Do a Google image search for "cornell box". It's a semi-standard test scene for global illumination renderers, and demonstrates the casting of coloured light by coloured objects onto other objects nearby.

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Wow, very interesting.

 

To me the Death Star surface chase/battle is impressive until the rebels steer into the portal. It all looks a little too dynamic, but you're caught up in the pace of the film. I don't know what it is, but there's something about the rebel fighters and Solo's Falcon turning into the Death Star's interior that blows the effect.

 

I'm trying to put my finger on it... I think it's the fact that the vessels during those particular frames are moving like model toys (which is what they are) as opposed to large fighter craft banking into massive structure. In essence those few frames seem unrealistically fast, regardless of the lighting. At that moment I think the illusion is blown, but the chase continues, and so the viewer forgets about it as the film's action continues to unfold.

 

It's all hindsight, but maybe a better shot might've been to show the fighters slowing some to adjust their path, and maybe showing the pilots themselves pulling G's as they try to slow and bank into the shaft. Then transition into a shot showing the fighters and Falcon rocketing into the Death Star's interior.

 

The downshot is that that would have slowed down the pace of the film, but it would reinforce the illusion.

 

More later... sleepy right now. :lol:

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While I've been doing this for a long time, it has been getting increasingly difficult to tell CGI from real no matter how practiced the eye. Of course, there is plenty of low-budget, low-end or unskilled CGI out there too, but there is also a lot of stuff that just gets accepted as real (especially when it is not some kind of wow-me move that gives it away).

 

Mars

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To me it seems like some CGI costs more than shooting the actual thing. I always hear about processor and rendering times, and then the cost to actually hire the army of artists to draw the models and paint the skins. It seems like, again this is just my opinion, that almost costs more to render some CGI than to actually build a set or hire an army extras and costume them for a shot.

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To me it seems like some CGI costs more than shooting the actual thing. I always hear about processor and rendering times, and then the cost to actually hire the army of artists to draw the models and paint the skins. It seems like, again this is just my opinion, that almost costs more to render some CGI than to actually build a set or hire an army extras and costume them for a shot.

 

I kept asking about that when I was doing a lot of vfx oriented articles in the late 90s. The vague answers all revolved around how much it cost to use the VFX house's motion control stage ... which never made any sense to me, since if they weren't using their stages, it would be more of a problem, right?

 

There are a handful of CG solutions that have succeeded like gangbusters (the SOLARIS remake had very credible space vessels), but I'd take a well built and properly shot miniature over it just about any time, assuming they didn't screw up the look by doing a scan that clipped the qualities that made the model look so good in the first place.

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