No, the blue screen errors were visible in first run, because I think I know which shot Zap
is talking about without even checking the photo. I started reading about blue screen in the 1960s (even ordering a professional trade book), because I couldn't figure out how they got the Enterprise in space. I knew it wasn't on wires, I knew it wasn't a cartoon or stop-motion animation, but I didn't know anything about blue screen or optical printing in those days. Now we can do it in 5 seconds on home computers.
Things we now take for granted were closely guarded secrets back then.