Back in the mid-1950s, if you wanted to make a giant monster you worked with a basic toolkit: Stock footage, dim lighting, and editing tricks. And yet somehow this mega-spider from 1955’s Tarantula is more convincing than today’s CGI mega-whatevers.
Maybe it’s just because tarantulas move in such a creepy way that they can’t help but seem scary when enlarged and unleashed on cows. Or maybe it’s been scientifically proven that tarantulas fill our brains with fear.
https://gizmodo.com/scientific-proof-that-the-scariest-thing-imaginable-is-5686525
https://www.youtube.com/watch?v=PIgU22nr2wg
If you like Syfy Movies of the Week, you need to check out Tarantula to see how it was done old school.
Tarantula via IMDB