Visible crew/equipment: While Dr. Mike is unsuccessfully trying to make supper Olive returns with the children, and after Olive says goodbye to them, when Dr. Mike closes the door a white T-mark is visible on the porch. (00:08:55)
The Great American Medicine Show - S1-E8
Visible crew/equipment: After Sully and Dr. Mike bring drunk Franklin into the clinic Sully leaves, and when Dr. Mike passes the partition as she walks toward Horace, the blue, yellow, and red chalk T-marks are visible on the floor. (00:10:25)
The Great American Medicine Show - S1-E8
Visible crew/equipment: While Myra is lying on the table before her surgery Dr. Mike tells her she's almost ready to begin, then just as Horace is about to stand up the orange T-mark is visible on the floor. (00:38:30)
Revealing mistake: When Rankin is gored by the white buffalo, in his last closeup the wood plank is visible at the back of the animal head prop, at the right side of the screen. (00:44:30)
Visible crew/equipment: The tip of the boom is visible every couple of seconds as Daniel shares a 'Sully story' during lunch at Grace's Cafe. (00:13:35)
Visible crew/equipment: When Kid Cole removes the noose from Jon's neck and helps him off the horse, in the next overhead shot there are multiple T-marks visible on the ground before the shot fades out. (00:37:50)
Answer: A Cooper was someone who made various things out of wood including wooden caskets and even barrels.