An electronic camera includes: (a) a first imaging stage comprising a
first image sensor; a first lens for forming a first image on the first
image sensor; and a first lens focus adjuster for adjusting focus of the
first lens responsive to a first focus detection signal; and (b) a second
imaging stage comprising a second image sensor; a second lens for forming
a second image on the second image sensor; and a second lens focus
adjuster for adjusting focus of the second lens responsive to a second
focus detection signal. A processing stage (a) selects the sensor output
from the first imaging stage and uses the sensor output from the second
imaging stage to generate the first focus detection signal, (b) selects
the sensor output from the second imaging stage and uses the sensor
output from the first imaging stage to generate the second focus
detection signal.