Continuity mistake: After both Dorothy and Scarecrow have oiled Tin Man's elbows, Dorothy pulls the Tin Man's arm down and we see her throw the apple that she's holding down behind him. In the next shot it reappears in her left hand. (00:41:55)
Continuity mistake: In the scene where the Wizard is about to bestow 'awards', the Scarecrow is lined up second from the left as the Wizard begins to speak. In the next shot while the Wizard is still speaking, the Scarecrow 'jumps' to the far right. (01:29:10)
Revealing mistake: As Dorothy is about to walk into the cyclorama (backdrop) as she leaves Munchkinland, Munchkins are blurred, including a Munchkin soldier on the very far right, who becomes transparent with the matted-in flowers. (00:33:40)
Continuity mistake: In the scene where the Wicked Witch in Munchkinland goes over to observe the ruby slippers on her dead sister's feet, when she is up close there's not much space between her and the slippers but when she turns around and says "they're gone," she's further away, then she's closer again in the next shot.
Visible crew/equipment: The seams in the floorboard under the Haunted Forest set can be seen several times under the leaves. The best is in the close-ups of Toto. (01:15:30 - 01:19:35)
Continuity mistake: The Tin Man starts chopping the Witch's door and it's not the same one we just saw three shots before. The wood is a different color and the dark metal brace has been polished in the close-up. (01:23:40)
Continuity mistake: When Dorothy is talking to the Scarecrow for the first time, the Scarecrow moves further down his pole between close up shots. (00:34:35)
Visible crew/equipment: There are multiple fragmented reflections of studio lights on Dorothy's bedroom window, as it rips off due to the twister. (00:16:20)
Character mistake: When Dorothy and the others enter the Haunted forest, the sign reads "Witches Castle One Mile." "Witches" is plural. To be grammatically correct, it should have said "Witch's Castle," if one witch, or "Witches' Castle" if more than one.
Suggested correction: Not necessarily. There was a time when apostrophes were not consistently used to indicate possession, and even today, usage varies. In earlier periods, the apostrophe was used more sparingly, and there was less standardisation in its application. Today, apostrophes aren't used on street names (e.g. Queens Road) and many pub names (e.g. The Bulls Head), etc.
Revealing mistake: When Toto reveals the Wizard by pulling the curtain aside, he doesn't use his mouth; the curtain is tied to the dog. Dorothy can even be seen later removing the rope.
Visible crew/equipment: Near the very beginning, when Dorothy is with Prof. Marvel, after she runs out of his trailer and the wind starts blowing, he follows her and goes towards his horse tied up outside. As he's walking towards the horse, you can see the shadow of a boom mic along his trailer. (00:14:55)
Continuity mistake: You see a Flying Monkey with Toto before he gets picked up. (01:15:30)
Revealing mistake: After the witch says "Hey scarecrow, wanna play ball" she throws a fireball at him. But you can see the ground catch on fire before the fireball hits the ground. (00:46:20)
Continuity mistake: At the start of the "lions and tigers and bears, oh my" sequence, Dorothy, the Scarecrow and Tin Man are all standing separately, then the shot cuts and they're suddenly arm in arm. (00:48:45)
Continuity mistake: Just before the Wicked Witch leaves Munchkinland she says to Dorothy, "just try to stay out of my way" and her broomstick is facing upwards. In the next shot it's facing downwards. (00:30:35)
Suggested correction: In between shots, in order to threaten Dorothy more, the Witch leaned down towards her more than in the first shot. Therefore, she had to lower the broom so she could do that without the broom getting in the way.
These shots are back-to-back. There's literally no time for her to have lowered the broom between shots. She would have had to have done it in 1/24th of a second... about 8 times faster than it takes you to blink your eyes once at normal speed. It's just not possible.
Continuity mistake: Glinda tells Dorothy, "Their magic must be very powerfulÂ…" and Dorothy has her left hand around Toto. In the next shot she's holding the flowers in front of her. (00:30:20)
Continuity mistake: When the Munchkins come out onto the Yellow Brick Road, one of them comes out of a sewer hatch on the yellow bricks. It's located on the ground in front of the first small white cottage with the thatched roof, right behind Dorothy's house. Throughout this scene, the dark hatch is visible whenever we see that specific location, such as when the Wicked Witch of the West asks, "Who killed my sister? Who killed the Witch of the East? Was it you?" but as Dorothy begins to "follow the yellow brick road", there is an overhead shot followed by a front shot and the dark hatch has disappeared.
Continuity mistake: There are two actresses playing Dorothy (and two dogs playing Toto) as she opens the door to Oz. The first is a stand-in wearing a dull colored dress in order to make it look black and white. After she opens the door and moves out of the way, Judy Garland is who we actually see walking through. Look at the different pleats on the two dresses. (00:19:25)
Continuity mistake: After the Tin man opens the door with his axe chopping its wood, Dorothy steps out and the door is totally fixed. One can see the unblemished door when the Lion removes his paw.
Visible crew/equipment: Studio lights are reflected in the Wicked Witch's large crystal ball, as Dorothy sits down and cries beside it, just before she sees her Auntie in it. (01:15:10)
