Electronic First-curtain Shutter
A hybrid shutter that begins the exposure electronically and ends it with a physical curtain.
Measured in
seconds
In depth
Starting electronically removes the vibration of a mechanical curtain accelerating from rest, which is the main cause of shutter shock in the 1/100 to 1/500 s range. Because the electronic start sweeps at a different rate from the mechanical finish, very fast shutter speeds can produce uneven exposure and truncated bokeh circles, so most cameras disable it above about 1/2000 s.
Examples in practice
Switching on electronic first curtain removes the faint doubling seen in 1/160 s handheld shots with a 100 mm macro.