Frank view about paintings put up (8)
I believe the answer is:
straight
'frank' is the definition.
(thesaurus)
'view about paintings put up' is the wordplay.
'view' becomes 'sight' ('sight' can be a synonym of 'view').
'about' indicates putting letters inside.
'paintings' becomes 'art' (I've seen this before).
'put up' says the letters should be written in reverse.
'art' back-to-front is 'tra'.
'sight' enclosing 'tra' is 'STRAIGHT'.
(Other definitions for straight that I've seen before include "Neat (of drinks)" , "Poker hand of 5 consecutive cards" , "Without deviations or curves" , "Honest - direct" , "Honourable" .)