Revealing mistake: When Zod takes the rifle out of the cop's hand the strings moving the rifle are seen, each by the side of the cop's cowboy hat when the rifle turns red.
Revealing mistake: The 3 villains break through the Daily Planet window and fly around the city. Before Zod stops by a beam, Non becomes transparent.
Revealing mistake: After the Marlboro truck scene, Superman throws Zod and he goes through an office window. The harness to make him fly is visible on his back.
Revealing mistake: When Ursa blows the helicopter away, the string holding it is visible.
Revealing mistake: When Non falls on Superman and breaks the concrete, the hole opens before Non falls on him.
Revealing mistake: When Non goes through the pavement, the hole reveals it's a foam made floor.
Revealing mistake: In the ice cave, when Superman makes himself invisible, watch Zod's head jumping slightly to the back, revealing where the scene was edited to achieve the effect.
Revealing mistake: In the ice cave, Superman throws a plastic S at Non. The wires moving it are visible.
Revealing mistake: During the big fight in Metropolis, the close-up of the pram shows its empty or with blatant bundled pieces of fabric to simulate some sort of baby.
Revealing mistake: When the Empire State antenna falls down the wires holding it are visible.
Revealing mistake: Near the end when Zod and his crew are blowing everybody away, there is a shot of two cars going into a department store and one flying right to left. There are also two "people" running away in this shot. They're dummies. One of the cars hits the person and he wobbles. Incredibly obvious. These aren't mannequins from the store either; they're on a track and follow a path from right to left.
Revealing mistake: When Zod picks up the guy in East Houston, you can see right through the guy. He's transparent.
Revealing mistake: When Superman is saying, "No, don't do it! The people!" you can see Christopher Reeve is trying his hardest not to laugh.
Revealing mistake: Right when the Metropolis fight is about to start, Superman flies to the Daily Planet and passes by a building. Check the pattern on the windows and you'll notice that the same small door on the left appears almost everywhere, revealing that a miniature was used.
Revealing mistake: The villains send cars flying through the air. This was achieved with detailed scale model cars in a scale model Metropolis. But in order to mimic the blown-away citizens they use cheap mannequins that move on some sort of conveyor belt. (01:43:50)
Revealing mistake: When the villains blow away the stuff in Metropolis, the fire hydrant falls down and reveals it wasn't fixed to the ground, a blatant prop.
Revealing mistake: At the Fortress, when the villains and Superman play the appearing/disappearing trick, there's a shot with 4 Supermen onscreen, a special effect which was achieved with stand-ins. The one in front of Zod, and especially the one next to Lois look nothing like Christopher Reeve.
Revealing mistake: When the phantom zone explodes it is a cheap pencil drawing animation.
Revealing mistake: When Luthor and Teschmaker are in the balloon, in the wide angle they both become coloured green due to the blue screen effect.
Revealing mistake: When Superman launches the Eiffel elevator in space and he flies back to earth, a white rectangle surrounds him where his image was superimposed to achieve the flying effects. (The Ultimate Collector´s Edition Box Set).
Answer: Superman was be able to kiss Lois in such a way that the heightened emotion wiped out her memory of his identity. To answer your second question, even though Lois promised not to tell anyone, Superman decided he does not want even her to know his secret identity.
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