How special effects are made in movies: from green screens to CGI

In 1993, viewers saw a live Brachiosaurus on screen for the first time — and half the audience stopped chewing popcorn. The secret of 'Jurassic Park' is that there are only about six minutes of computer-generated dinosaurs; the rest are giant animatronic puppets, hydraulics, and wet rubber. This is the main paradox: special effects in movies are almost never 'just one thing.' It's always a layered pie of plywood, smoke, green fabric, and mathematics. Let's break it down by layers.

Practical effects: when it's easier to blow something up for real

A practical effect is anything that actually happened in front of the camera. An explosion, rain from a sprinkler, makeup, a puppet, a stunt. Sounds archaic? Tell that to George Miller, who sent one hundred and fifty real cars into the Namibian desert for 'Mad Max: Fury Road' and wrecked most of them. Computer work was also involved — erasing cables, painting in the sky, and Charlize Theron's right arm — but the truck flip was a real flip of a real truck.

Why do directors still cling to this:

• Light behaves honestly. Real fire reflects on the actors' faces by itself — it's free and perfect.
• The actor has something to react to. Not everyone can play horror in front of a tennis ball on a stick.
• Physics doesn't require adjustment. Dust knows how to swirl by itself.
• It doesn't become outdated. Rewatch 'Alien' — Giger's rubber creature is still frightening.

Miniatures that are shot up close

A separate religion — 'bigatures': models the size of a garage. Rivendell and Minas Tirith in 'The Lord of the Rings' were built by hand, laying tiles one by one. Christopher Nolan also built ship models for 'Interstellar' and filmed them on film. The logic is simple: the camera believes in volume. A real shadow from a real object in real fog can be counted, but it's expensive and time-consuming.

Chroma key: why is the background green?

The actor stands in front of a neon green wall, waving their arms, and then finds themselves on the deck of a spaceship. The technology is called color keying or chroma keying: the software finds all pixels of a specified shade and makes them transparent. Green is chosen not for aesthetic reasons — there is almost no green pigment in human skin, so cutting it out is the safest option. Blue is used when there is a green costume or a lot of foliage in the shot.

Chroma key failures are almost always about light. If the background is unevenly lit, 'ragged' edges appear. If green reflects on the actor's cheek (this is called spill), the character glows like a cucumber. And if the operator filmed a person with soft diffused light, and then placed them in the desert at noon, the viewer's brain will scream 'fake' before it can understand why. Therefore, proper sets light according to the future background, not the other way around — and it becomes clear here, what to watch in the evening, to hunt for seams in the frame yourself.

CGI: computer graphics in cinema layers

CGI is not a 'make it pretty' button. The path of a single frame looks something like this: a modeler sculpts the geometry, a texture artist paints pores and scratches, a rigger inserts a digital skeleton, an animator sets the movement, shading describes how the material reacts to light, then rendering calculates the image, and a compositor combines everything with the live shot, adding film grain and a slight dirt on the lens. One frame of a blockbuster can easily take several hours of machine time — and there are twenty-four such frames in a film per second.

By the way, the engines that calculate this beauty have long moved to the neighboring industry: Unreal Engine powers both the virtual sets on the set of 'The Mandalorian' and what you play at home. The technology is the same — it just has time to think about the frame in cinema, while in a game it has thirty milliseconds. If the topic of visuals resonates with you not just on screen, we have party games — the same graphics work in real time.

Motion capture: the actor inside the monster

Mo-cap is not 'the computer drew the character.' It's a suit with markers, dozens of infrared cameras around the perimeter of the studio, and a live person performing. Andy Serkis as Gollum and Caesar from 'Planet of the Apes' performed everything: the back, the breath, the pauses. A separate camera on a boom in front of the face captures the facial expressions — this is how performance capture is born. The animator then cleans up the data and transfers it to the digital body, but the original emotion belongs to the artist. This is why mo-cap characters are more alive than pure animation: they retain the human micro-movements that no one can invent from scratch.

De-aging and digital faces

Rejuvenation is the most nerve-wracking territory. In 'The Irishman', Scorsese filmed De Niro with a special three-camera setup without markers on his face, so the system could reconstruct the volume and provide a younger version. The result is controversial: the face looks younger, but the gait of a sixty-year-old man remains. The viewer's brain catches such discrepancies and falls into the 'uncanny valley' — that feeling when it's almost like a person, but something is off. This also applies to stories about the digital resurrection of actors: technically possible, ethically a minefield, which is discussed in the section about cinema and stars debated with enviable regularity.

Why special effects in movies sometimes look plastic

Bad CGI is usually not about the artists' lack of skill, but about deadlines. The studio is revising the third act a month before release, leaving the team with weeks instead of six months — and an unfinished version makes it to the screen. Plus, typical troubles:

• Perfection. The real camera shakes, catches glare, and slightly blurs motion. The sterile clean computer object reads as foreign.
• Weight. The digital object often flies too easily: mass is felt through inertia, and it is forgotten.
• Light does not match. Shadows on the hero come from the left, while in the background they come from the right — you do not realize this, but you feel it.
• Too much of everything. When there are 400 digital beings in the frame, the eye has nothing to latch onto.

It is telling that the best visual effects are usually those you don't notice: erased wires, a digitally added floor of a building, a removed film crew from the shot. Space movies are champions of invisibility here — capturing vacuum, weightlessness, and scale is almost impossible, so the best space movies rely on effects in almost every frame, and the eye rarely stumbles.

How it works on set today

The main change in recent years is virtual production. Instead of a green wall, a curved LED screen as tall as a three-story building is set up, displaying a ready 3D world that moves in sync with the camera. The actor sees a sunset, not a cloth; the metal on their costume reflects the real sunset; the director watches the final picture right on set. This is how 'The Mandalorian' was filmed, and since then, such studios have been built all over the world.

But this is not a silver bullet: the screen falters on extreme close-ups, and the scene needs to be almost completely imagined before shooting. So the question of 'how films with effects are made' is still solved with a mix. The dust is real, the explosion is real, the dragon is digital, the wires are erased, the background is drawn. The magic is in the seam that you didn't see.