VFX, SFX, CGI, FX and special effects are often used as if they mean the same thing. They don’t. Each describes a different way of creating the impossible on screen, and each leads to a different career. Here is the plain-language difference.
The short answer
| Term | What it is | When it happens | Example |
|---|---|---|---|
| SFX (special effects) | Physical, practical effects created for real on set | During filming | A controlled explosion, rain machines, smoke, prosthetic make-up, a car flipped on a rig |
| VFX (visual effects) | Digital changes made to filmed footage | After filming, in post-production | Removing safety wires, adding a city skyline, multiplying a crowd, combining actors with a digital creature |
| CGI (computer-generated imagery) | Any image created in 3D software | In production or post-production | A digital dragon, an animated film, a product render, a game character |
| FX | Shorthand for effects; in studios, “FX” usually means simulations | In post-production | Fire, smoke, water, destruction and particles built in software such as Houdini |
“Special effects” and “SFX” are the same thing. Note that in sound departments, SFX can also mean sound effects; on a film set it means practical effects.
SFX: real effects on set
Special effects are created physically in front of the camera: pyrotechnics, wind and rain machines, breakaway glass, animatronics and prosthetics. Their advantage is that actors react to something real and the camera captures real light and physics. They need specialist technicians, careful safety planning and often licences, which is why SFX is a smaller, more specialised field.
VFX: changing the footage afterwards
Visual effects work with what was filmed. Artists remove what shouldn’t be there (wires, rigs, modern signs in a period film), add what couldn’t be filmed (a crowd, a monster, a collapsing building) and combine everything into a believable shot. The main VFX jobs are rotoscoping, paint and clean-up, matchmove and tracking, compositing, FX simulation and matte painting.
CGI: images made in a computer
CGI is a tool rather than a stage. Most modern VFX uses CGI, for example a 3D creature composited into live footage, but not all VFX is CGI: wire removal or combining two filmed takes uses no 3D at all. And not all CGI is VFX: fully animated films, product visualisation and game art are CGI without any filmed footage.
How they work together on one shot
Take a car explosion in an action film. The SFX team stages a real, controlled blast with a stand-in car. The VFX team removes the rig that flipped it and extends the fire and debris. An FX artist simulates extra smoke and sparks, and a CGI model of the car is used for an angle that would be too dangerous to film. The audience sees one seamless moment.
Software used
- VFX and compositing: Nuke, After Effects, Silhouette and Mocha for roto and tracking
- CGI and 3D: Maya, Blender, 3ds Max, ZBrush, Substance
- FX simulations: Houdini, plus Blender and Maya tools
- SFX: mostly physical equipment rather than software
How AI is changing effects work
AI now speeds up rotoscoping, clean-up, upscaling and set extensions, and can generate background elements from a prompt. It hasn’t replaced the judgement needed to make a shot look real: matching light, grain and motion. Read what AI changes in animation, VFX and design.
Which should you learn?
- Interested in film shots and realism? Start with VFX: compositing, roto and tracking. See our VFX Pro course or the Certificate in Video Editing and VFX.
- Prefer building creatures, objects and worlds? Start with CGI and 3D: see the CGI Diploma or the Diploma in 3D Animation.
- Want to do both? The Advanced Diploma in Animation and VFX Prime covers animation and VFX together.
Read more about careers in VFX and 3D animation, or book a free demo class.
Common questions
Is CGI the same as VFX?
No. CGI is imagery made in a computer; VFX is the process of altering filmed footage. Most VFX uses CGI, but VFX also includes work like wire removal and compositing that uses no 3D at all.
Is SFX the same as special effects?
Yes, on a film set SFX means special (practical) effects. In audio, SFX can also mean sound effects.
Which pays more, VFX or CGI?
They overlap heavily, and pay depends more on your specialisation, studio and showreel than on the label. Compositors, FX artists and lighting artists with strong reels are in steady demand.