What is the difference between Auto Iris and
Direct Drive Lenses?
An Auto Iris lens is one that automatically adjusts its iris for
changes in the scene lighting levels. The motor that opens and closes the
iris is driven by an Amplifier that processes a small electronic signal
changing with the light level.
A Direct Drive 'DD' lens does not have this Amplifier and can only
operate with a camera fitted with one.
A camera specification will indicate the available output options.