The latest episode of the VFX artists reaction series takes a deep look at four very different shots, spanning from 1948 stop motion to a modern TV show's opening sequence. The artists break down how each effect was achieved, what worked, what didn't, and why some of the most impressive tricks are also the simplest.

The series, known for its forensic analysis of visual effects, brought in clips chosen by the team themselves. One shot in particular has been bugging one of the artists for his entire life: a scene from the 1948 film Mighty Joe Young.

The Serenetti switch and a young Ray Harryhausen

The Mighty Joe Young clip shows a stop motion gorilla interacting with a real lion inside a cage, with a moving river in the background. The artists immediately recognized the work of a young Ray Harryhausen, who was working as an assistant to Willis O'Brien on his first major motion picture.

The shot is a classic example of double exposed film. The lion was filmed first in a cage element with a black frame around it, leaving that part of the film unexposed. Then the stop motion gorilla was animated frame by frame, with the animators counting frames between the lion's actions to sync the gorilla's reactions.

But the complexity doesn't stop there. As the cage tips over, the artists noticed a flat gray screen appearing on the cage's surface. They identified it as a rear projection technique: a separate film of the lion was projected onto a screen built into the cage, allowing the stop motion gorilla to appear to interact with the lion in real time. The artists pointed out a tiny stationary dot in the bottom right of the cage, confirming it was a projection surface.

The team marveled at the frame by frame exposure process: expose the lion frame, cover the lens, expose the stop motion frame, cover again, advance to the next film frame. The result is a seamless composite that still holds up today. "This is a really clever and well executed shot, even by modern standards," one artist said.

The artists also noted how the floor plane changes angle during the tilt, indicating that the cage was actually being physically tilted. Then as the cage continues to tilt, the projection surface tilts with it, causing a slight parallax shift. It's a complicated magic trick, all done without any digital tools.

Congo's laser gun: a mix of practical and digital

Next up was a clip from the 1995 film Congo. The artists were genuinely impressed by the movie's representation of a laser gun. A character mines "monkey crystals" from a volcano, crafts a laser gun, and proceeds to zap attacking monkeys.

At first glance, the artists thought some of the effects might be practical. But on closer inspection, they determined that almost everything is digital. The lasers themselves are simple white strokes with an outer glow, straight out of Photoshop, with no motion blur. The sparks are basic comps. However, the rock explosion is real: a practical pyrotechnic charge that bursts on cue.

The team broke down the layers of the shot. Two monkeys in the foreground go down first, with digital head shots added. The rock has a real charge that bursts, casting a genuine shadow on the rock surface. Then the foreground monkey's chest erupts in fire, also practical. On top of that, the laser beam was masked to appear as if it passes through the monkeys, and some fire elements were added in front of the lens.

The artists praised the overall execution, noting that good camera motion and composited lighting can sell even a simple digital laser. "Basic techniques applied well hit just as hard," one artist said.

Limitless: the infinite zoom made simple

The opening credit sequence of the 2011 film Limitless features a trippy zoom through a city, appearing to travel forward through space without any parallax. The artists explained that the shot is actually a constant zoom in, not a forward push. The effect can be achieved by filming wide, medium, and tight versions of the same scene and stacking them in compositing software.

One artist mentioned that this technique is similar to a "Snider cam" rig used by Zack Snyder, where three cameras capture wide, medium, and tight simultaneously. By layering those clips, you multiply the resolution and can zoom much deeper than a single camera would allow.

But the undervalued aspect, according to the artists, is the amount of masking required to blend the clips seamlessly. Even with a three camera rig, there will be slight parallax differences between the shots. One artist recalled spending days on masking for a similar effect. The lesson: don't be intimidated by complex VFX. Basic techniques, when executed with care, produce results that look just as impressive.

The Pitt: why does that opening sequence look weird?

Finally, the artists tackled an opening sequence from the medical drama The Pitt, set in Pittsburgh. Viewers had sent the clip to the VFX team, asking why it looks off. The artists initially struggled to pinpoint the issue.

The sequence shows a doctor walking into a hospital, followed by a truck and motorcycle driving across a bridge. The team noticed that the actor looked slightly rotoscoped against the background. The motion blur on trees didn't match between left and right sides. The sky was clearly replaced.

Then they noticed the shadows. The truck's hood showed high noon sunlight shadows, yet the scene is supposed to be 7:00 AM. The artists theorized that the production filmed the shots at midday but needed to make it look like early morning. To achieve that, they replaced the sky and likely the entire road surface to eliminate unwanted shadows from trees.

One artist connected with a Redditor who works in the building shown in the shot. The real location does exist; the building is actually there. But the ground and shadows were digitally replaced. This explains why the truck looks oddly bright, with daytime reflections, while the environment is darkened.

The story gets more interesting: the production apparently filmed these shots without a full permit. They had a permit to location scout the bridge, but they went ahead and captured footage anyway. The city of Pittsburgh reportedly didn't object because they value the business.

The motorcycle clip on the bridge shows a CG road surface, with the bike appearing to float above it. The tire doesn't even spin. The artists concluded that the entire road was replaced to match the desired lighting and remove unwanted shadows, leaving only the truck and actor as real elements.

The takeaway from this shot is that even small inconsistencies, like a floating bike or mismatched shadows, can break the illusion. The VFX work was done to fix a production issue (wrong time of day) but introduced new artifacts that betray the effect.

What these shots teach us about VFX

Across all four examples, a common theme emerges: the best visual effects are often invisible, and the most memorable tricks rely on understanding the fundamentals of light, motion, and compositing. Whether it's a frame by frame double exposure from 1948 or a modern digital road replacement, the goal is the same: to make the audience believe what they see.

The artists also stressed that basic techniques, applied carefully, can produce results that rival big budget effects. The Limitless zoom is a simple scale and mask operation. The Congo laser is a white stroke with outer glow. The Mighty Joe Young shot is a clever use of rear projection and stop motion. None of these required cutting edge software; they required patience and an understanding of how the eye perceives reality.

For filmmakers and VFX artists alike, the lesson is to focus on the fundamentals. Don't be intimidated by flashy CGI. A well planned practical effect, a careful composite, and attention to detail will always trump a complex digital effect that isn't grounded in physical reality.