After George Reeves' death, producers considered continuing the series with Jimmy Olsen becoming the main character and including stock footage of Reeves as Superman. Jack Larson, however, rejected the idea.
It is now common knowledge that Clark Kent's Earth parents were named Jonathan and Martha. However, in the first episode, Adventures of Superman: Superman on Earth (1952), Kent's parents were named Eben and Sarah. This is because the comics themselves were inconsistent with the Kents' given names until the characters became major players in "Superboy" comics stories at about this same time. The names Sarah and Eben were first used in the novel "The Adventures of Superman" (1942) and in the first Superman serial.
In the early episodes, George Reeves wore glasses without lenses in them when he played Clark Kent. As he got older Reeves eventually needed a real prescription for eyeglasses, so he began wearing his own glasses, as can be seen in many later episodes when you can see the stage lights being reflected off the lenses.
In the early seasons wire work was used to create some of the flying scenes. During the course of this work there had been some minor mishaps, but on one occasion the support wires snapped, causing George Reeves to be dropped to the floor. He refused to do anymore wire work. This is why episodes in the early seasons would show Superman taking off in flight within the frame, but in later seasons he would run toward the camera, hit a springboard hidden below frame and leap out of frame.
John Hamilton, who played Perry White, had trouble remembering his lines. The solution was to film him sitting at his desk, with the desk littered with papers--including the script--so he could glance down to be prompted for his next line.
When the series was filmed in black and white during its first two seasons, George Reeves wore a brown for red, gray for blue and white for yellow costume. When the show began filming in color in 1954, he switched to the trademark red and blue suit.
George Reeves wanted to quit the series after the third season. Kirk Alyn, who played Superman in the 1940s film serials, was offered the chance to replace Reeves but turned it down. Reeves tried to produce his own series titled "Port of Entry", but when he was not able to secure financing, he returned to "Superman" with an increase in salary.
For the first season of the series, the E. Clem Wilson Building in Los Angeles was used for the exterior shots of the Daily Planet. Throughout the rest of the series, the building seen as the Daily Planet Building is really Los Angeles City Hall. The rest of the buildings that stand in for "Metropolis" in street scenes were back-lot facades at the old RKO Forty Acres lot in Culver City, which earlier had been Atlanta for Gone with the Wind (1939), and would later serve as Mayberry for The Andy Griffith Show (1960).
Because of a limited budget, all episodes were filmed out of sequence, with all scenes in Perry White's office, for example, being done at one time. This explains why the actors always seemed to wear the same clothes in every episode.
When the series was picked up by Kellogg's, the breakfast cereal manufacturer, some of the cast members were able to make extra money by appearing in Kellogg's commercials. This did not include Phyllis Coates or Noel Neill. It was felt that Lois Lane having breakfast with Clark Kent was too suggestive.
An often talked-about mistake in the show is that Superman would duck when a thug would throw his empty gun at him. While this is often attributed to George Reeves not wanting to be hit by a prop gun, it was actually his stunt double Dale Van Sickel who ducked. This mistake only happened once, in Adventures of Superman: The Mind Machine (1952)). If you watch the fight scene closely, you can see that a stunt double is used some of the time and that it is that double who ducked. The fan group for the Adventures of Superman (The Adventures Continue) has published more details about Van Sickle making this mistake.
George Reeves was 44 years old during the filming of the sixth and final season, making him the oldest actor to have ever played Clark Kent / Superman in live-action. Photos exist of Reeves at that age with almost completely gray hair.
The Superman costume was padded to make it appear that George Reeves had greater bulk. However, Reeves himself did most of the stunts, which required impressive athletic ability including jumping from substantial heights (to simulate Superman landing in the frame), hitting a springboard with sufficient force to propel him out of frame (to simulate Superman taking off in flight), swinging through windows, and hours spent doing wire work and being in a body support platform to create the scenes of Superman flying.
The series was honored on its 50th anniversary when the Los Angeles County Board of Supervisors proclaimed July 10-16, 2001, as "Superman Week." A proclamation was presented to Paul Levitz of DC Comics in a ceremony that was also attended by Jack Larson, Noel Neill, Mrs. Robert Shayne, Mrs. Jerome Siegel, Robert Rockwell, Jeff Corey and Walter Walbrecht, vice president of Warner Brothers. Season 3, Number 4 was named "Superman Week" honoring the Man of Steel and was first broadcast on 14 May 1955.
George Reeves was suspended by cables when he appeared to be flying during the first two seasons. In subsequent seasons he was positioned on a molded platform contoured to fit his body, and wore his costume over it. Exterior landing scenes were accomplished by having Reeves jump off of a ladder. When he came through the window, he would jump and swing in from a bar positioned outside the window.
In every episode where Superman enters Perry White's office through the window (presumably after first landing on an undisclosed ledge or small balcony), Superman sidles in between the windows' large tilted louvers. There is never any suggestion that he must first open a window or sliding glass door to come through the window.
In the first season, when Phyllis Coates played Lois Lane, she got star billing along with George Reeves. When Noel Neill took over the role in the second season, her character was reduced to featured billing.
The train seen in the opening sequence for the first two seasons is a streamline steam locomotive. Starting with the third season, which was filmed in color, a modern diesel locomotive was seen instead.
After the deaths of John Hamilton (Perry White) and series star George Reeves (Clark Kent/Superman) in 1958 and 1959 respectively, the producers had planned to cast Kirk Alyn as Kent/Superman and Pierre Watkin as Editor White, as they had originated the roles in the two Columbia Pictures serials. Instead, the series was cancelled.