Visible crew/equipment: As the General gets in his staff car and it leaves, the film crew and equipment are reflected on the sides.
Visible crew/equipment: As Schultz drives away from the boys, the camera crew and equipment is reflected in the window.
Visible crew/equipment: As Schultz looks at the prisoners after being told of the escape, the studio lighting rig is reflected on his monocle.
Visible crew/equipment: As the man gets in the passenger side of the car after the agreement is signed, the studio lighting rig is reflected in the glass.
Visible crew/equipment: As Klink and Schultz approach the barracks where Le Beau is "weightlifting", there is a cord or cable along the ground that would be for studio equipment.
Visible crew/equipment: As the car with the kidnapped Klink takes off, the Stalag 13 buildings are reflected in the windows, along with the camera equipment and lighting. (00:01:20)
Visible crew/equipment: As Klink's car pulls up, and Klink comes around the front of it, the shadow of the camera is visible.
Visible crew/equipment: As Hogan and Le Beau crawl through the car and shut the door, the camera rig, equipment, and cameraman are reflected in the window.
Visible crew/equipment: As Klink gives the info on the Tiger tanks, in the close ups, the studio light is reflected in his monocle.
The Informer - S1-E1
Visible crew/equipment: As Burkhalter looks down at the floor under the water tower, the studio lighting positions are distinguishable on the visor of his cap.
Visible crew/equipment: As the two German officers come out of Klink's office and approach the radar truck after Kinch leaves, the shadow of the cameraman, the camera, and the camera tripod are plainly visible on the left side of the scene on the ground.
Visible crew/equipment: When the radar truck comes into the camp, as it slows, you can see the lighting rigs for the cameras.
A Klink, a Bomb and a Short Fuse - S2-E8
Visible crew/equipment: When Burkhalter gets out and goes toward the office, as the camera pans to follow, you can see the shadows of the film crew and equipment.
Movies Are Your Best Escape - S1-E8
Visible crew/equipment: When the staff car is entering and coming to a stop in the compound, the reflection of the crew member, camera and lighting rig can be seen in the chrome of the radiator.
Go Light on the Heavy Water - S1-E9
Visible crew/equipment: When the staff car entering the compound stops, you can see a reflection of the crew member stopping the car, the light rig, and the camera in the chrome.
Happy Birthday, Adolf - S1-E17
Visible crew/equipment: When spying on a gun emplacement, LeBeau is dressed as a little old lady. When putting on his shawl before going back, you can see the studio lighting reflected on the glasses he wears.
Anchors Aweigh, Men of Stalag 13 - S1-E16
Visible crew/equipment: When in Klink's office, Hogan gives Klink the bum's rush, convincing him that he's tired. After Klink sits, the camera pans around. As it does so, you can see the shadow of the camera rig.
Will the Real Colonel Klink Please Stand Up Against the Wall? - S4-E13
Visible crew/equipment: When Hogan opens the window, there is a reflection of the studio lighting on the top pane.
Watch the Trains Go By - S4-E19
Visible crew/equipment: When Klink is by the fence acting busy and talking to Schultz, twice you can see the shadow of the camera on Klink's overcoat.
The Antique - S5-E12
Visible crew/equipment: When Burkhalter first comes into the office, the camera rolls a little closer. As it does, you can see the shadow of the camera on Burkhalter's arm.
Answer: It's a comedy, not a documentary.
stiiggy
Perhaps it was counterfeit. There are numerous episodes where they deal in counterfeit monies.