February 19, 2026
From saltwater to saltiness
Old School Visual Effects: The Cloud Tank (2010)
Ink-in-water movie magic sparks nostalgia—and a spicy roast
TLDR: Old-school cloud tanks make movie clouds by layering saltwater and freshwater and injecting paint, seen in classics like Close Encounters and Raiders. Commenters swooned over tactile magic, shared recs like Roman De Giuli’s Emitter and Light & Magic, and roasted the author’s film taste.
Forget soulless CGI—today’s star is the cloud tank, a gigantic glass aquarium where filmmakers layer salty water below and fresh water above, then inject paint to bloom into stormy, otherworldly clouds. It powered the eerie skies of Close Encounters, the wrath in Raiders, and even a tornado in Poltergeist—and yes, someone literally jumped on a drain hose to part the “clouds” like movie Moses.
Hacker News went full nostalgia. xfeeefeee cheered and pointed to ink-in-water artists, hyping Roman De Giuli’s Emitter. mgot loved the piece, then threw shade at the author’s “Single Minded Movie Blog,” calling it some of the worst movie takes they’ve seen—cue popcorn. BoredPositron chimed in with homework: watch the Light & Magic doc on early visual effects. Side quests included Corridor Crew recommendations and “ink over pixels” memes.
The vibe? A tug-of-war between practical magic and digital convenience, with the crowd swooning for messy, unpredictable wizardry over sterile computer perfection. The biggest laugh: cloud tank chaos is uncontrollable, but so are the comments. Today’s forecast: 100% chance of drama, with scattered recommendations and one very salty roast.
Key Points
- •A cloud tank is a practical VFX technique using layered salt and fresh water to create cloud-like effects by injecting paint at the density interface.
- •Lighting, camera speed, and other variables shape the resulting imagery, which is inherently unpredictable and often requires extensive shooting.
- •Cloud tank elements are composited with live-action or model photography, with additional animation and lighting effects added in post or during capture.
- •Scott Squires devised the specific Close Encounters setup (per Douglas Trumbull); ILM used the same tank and approach on Raiders of the Lost Ark.
- •Notable examples include Close Encounters’ alien-cloud sequences, Raiders’ Well of Souls and Ark opening (including Gary Platek’s hose trick), and Poltergeist’s storm and tornado shots.