Impressive electronic image (4)
I believe the answer is:
epic
'impressive' is the definition.
(epic can mean grand or impressive)
'electronic image' is the wordplay.
'electronic' becomes 'e' (as in e-mail or e-books).
'image' becomes 'pic' (short for picture).
'e'+'pic'='EPIC'
(Other definitions for epic that I've seen before include "Heroic; saga" , "Vast in scale" , "Colossal" , "Tale of heroic deeds" , "A long poem or book with adventurous theme" .)