Artist's image equally small and ordinary (7)
I believe the answer is:
picasso
'artist's' is the definition.
(Picasso is an example)
'image equally small and ordinary' is the wordplay.
'image' becomes 'pic' (I've seen this before).
'equally' becomes 'as' (synonyms).
'small' becomes 's' (abbreviation - e.g. clothes size).
'and' is a charade indicator (letters next to each other).
'ordinary' becomes 'O' (abbreviation e.g. O-Levels).
'pic'+'as'+'s'+'o'='PICASSO'
(Other definitions for picasso that I've seen before include "So aspic is out for the Spanish artist" , "Pablo ,,,,,,,, great late Spanish artist" , "Spanish painter and sculptor" , "Spanish painter, d. 1973" , "Cubist artist" .)