Popular TV, lesser picture? (5)
I believe the answer is:
inset
'lesser picture?' is the definition.
(small picture in an article)
'popular tv' is the wordplay.
'popular' becomes 'in' ('in' can mean trendy).
'tv' becomes 'set' (television set).
'in'+'set'='INSET'
(Other definitions for inset that I've seen before include "Piece sewn into a garment" , "It could be stuck between pages" , "Piece introduced" , "Something placed into another using tines" , "Minor figure" .)