About twenty minutes into the movie, Marion has returned to her apartment with the $40,000 and is deciding whether to take the money and flee to California. As she looks at the money lying on the bed the camera zooms in to the envelope containing the cash. Notice the shadow of the camera on the bed as it nears the money.
Although letterbox allows you to see the whole picture, the overall screen image size is reduced, thus reducing the resolution of the video image, obscuring detail.
I noticed this too. It's quite a large blooper considering what a perfectionist Mister Hitchcock was. They said they made the remake to match his 1960 version exactly but I didn't notice any camera man shadow on the bed.