Not subtle, but clear (7)
I believe the answer is:
obvious
I believe this clue is a double definition.
'not subtle' is the first definition.
(I've seen this before)
'clear' is the second definition.
(similar in meaning)
'but' is the link.
(Other definitions for obvious that I've seen before include "Perfectly plain and clear" , "Clear; easy to see" , "Plainly seen" , "Patent" , "Unmistakable" .)