Many people would be surprised how much info you can find on Reddit. Did you know how Hollywood makes their movies? Did you know that Reddit knows all about it? If you search Reddit on Movie Magic you can find tons of info. Using your google-fu skills you can find a great a lot more.
I am going to give you the movie magic from two threads. One is just called Movie Magic and the other is called Stunning movie magic from Stan Winston Studios. You can find the imgur links within the Reddit threads and there are lots of great comments with more links there too. To make your life easier I will just post the best images below with the title of the movie that the images are from.
Indiana Jones and the Raiders of the Lost Ark
Starwars The Empire Strikes Back
The Lord of the Rings
Terminator 2: Judgement Day