"Small telescope"

This is a reversal clue - look for indicators like 'back', 'returned', 'up' (in down clues), or 'west' (in across clues)

Break down the clue into definition and wordplay parts

Answer: FINDER | Definition: 'Small telescope' | Wordplay: FINER=”of superior quality”, around the first letter/”cap” of D-[etachable]