I went back to the museum yesterday to document the banding effect at different shutter speeds. I kept the iso at 1600 when possible adjusting the f number to compensate and only in the last two increasing the iso to go all the way up -not linear, I think, but close-
I took the 1/50th speed reference given by Birna as starting point. Going slower didn´t make much difference so I stopped at 1/13th. Going in the other direction probed interesting so I went all the way to 1/6400th of a second. I think the reference of "like a bad synchronized high speed flash" is accurate.
From 1/100th the banding is subtle but cleary there and gets worse fast.
I think it shows the approach by Nikon to achieve high speed shutters with slower read-out.
I also added a picture of the lights and a mixed lighting situation.