In TV, one sees the smaller picture (5)
I believe the answer is:
inset
'the smaller picture' is the definition.
(I've seen this in another clue)
'in tv' is the wordplay.
'tv' becomes 'set' (television set).
'in'+'set'='INSET'
'one sees' is the link.
(Other definitions for inset that I've seen before include "Thing inserted" , "Reduced image" , "Something inserted" , "It could be stuck between pages" , "Magazine feature" .)