Two features in green type of camera (7)
I believe the answer is:
pinhole
'type of camera' is the definition.
(pinhole camera)
'two features in green' is the wordplay.
I cannot really understand how this works, but
'in' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for pinhole that I've seen before include "little gap" , "This may let in a chink of light" , "Small puncture" , "Tiny aperture" .)