Suppose that you have a crucial emotional shot of Jennifer Connelly looking distressed while talking on a mobile phone. You were happy with her performance at the time, but in the context of the film, you realize she needs to take it to a whole new level of distress. If you were George Lucas or the lady that wrote Twilight, the solution would be pretty simple: you would just dub in a line where Jennifer Connelly states, "I am distressed! Very, very distressed!" Meanwhile, directors capable of understanding human emotions might dial that back a few notches and simply add a digital tear rolling down her cheek.
That's only the tip of the iceberg as far as performance alterations. As the linked article mentions, "Visual effects experts privately admit to changing actors' expressions: opening or closing eyes; making a limp more convincing; removing breathing signs; eradicating blinking eyelids from a lingering gaze; or splicing together different takes of an unsuccessful love scene to produce one in which both parties look like they are enjoying themselves."
In the future, if technology advances far enough, we could see a visual effects equivalent of the Auto-Tune, software that could add any emotion to any actor, possibly spelling the end of ironically enjoying Keanu Reeves performances, which would be a shame.
Superman's main features were always supposed to be his chiseled face, his spit-curl and the big S symbol on his chest, and not his genitals. During production of the Superman Returns movie, Brandon Routh's mighty package allegedly became a distraction.
Shape and size became vital issues within the costume department, and digital effects were considered to reduce the size of the package in post-production. After a great deal of discreet work, children everywhere were saved from learning that men and women are different. And that some men are way different.
There is no indication of what "inside source" originally leaked the "Superman's dong is just too huge" rumor, but in our minds we picture a shadowy, Brandon Routh-shaped informant.
On the side of equal opportunity, Lindsay Lohan's breast size was allegedly reduced in Herbie: Fully Loaded, preserving one audience segment while alienating another. Lending credence to that rumor is the fact that Lola VFX, a well-known digital cosmetic enhancement shop, worked on the film.
Music videos are also a lucrative area for post-production fixes, one of the most unfortunate being adding digital panties to Carmen Electra in a Li'l Kim video after an unintentional flash.
On the complete opposite end of the spectrum from the family-friendly modifications in Superman Returns and Herbie, we have Paul Verhoeven's Hollow Man, based on the classic H.G. Wells novel The Invisible Rapist. It attempts to answer the age-old question: What would you do if you were a huge jerk that was able to become invisible? It's an important philosophical question that apparently can't be answered without showing penis. Like, a lot.
Kevin Bacon gets to showcase his manhood in possibly more ways than any other film has ever showcased a wiener. Whether it be plain old nudity, or heat vision swinging dong...
... or skinless man dong...
... or underwater dong...
... or shaking-off-water dong...
... or dong passing through smoke.
Now, the dong passing through smoke is barely visible, but it's important to take note of, because Verhoeven very specifically instructed artists to ensure it was visible. It was vital to him that Kevin Bacon's invisible penis be apparent in as many shots as possible.
While the heat vision shot only involved taking regular footage of Kevin Bacon walking around naked and running it through a filter, the water shots and the smoke shots specifically required an entire CG Kevin Bacon to be built, with CG joints and controls on every part of the body, including the penis, all controllable by animators, allowing them to increase penis swing on the smoke shot, for example, if necessary. And Verhoeven felt it was necessary.
Rumors also indicate that Kevin Bacon himself, after viewing some of the shots, discreetly requested some modifications using the universal language of dong description: he nodded toward the dong, held his hands some distance apart and then increased the distance.
We can laugh, but what man reading this wouldn't have done the exact same thing?
And check out some movies where a little CG was desperately needed, in The 5 Most Half-Assed Monsters in Movie History. Or find out about Hollywood is using more than just CGI to rip you off, in 5 Innovative Ways Hollywood Is Screwing You Over.
And head over to Cracked.com's Top Picks to see evidence that we don't need CG effects to enhance our dongs.