Visual representation in viewing Raphael (5)
I believe the answer is:
graph
'visual representation' is the definition.
(I've seen this before)
'in viewing raphael' is the wordplay.
'in' says the answer is hidden in the clue.
'GRAPH' is hidden in the letters of 'viewing raphael'.
(Other definitions for graph that I've seen before include "Mathematical plot" , "Visual representation" , "Diagram showing relationships between things" , "Drawing showing quantities plotted on axes" , "Geometrical diagram" .)