Shutter __, Press This Button to Take a Photo

This page is the CodyCross answer for the clue below from La Bella Roma, Group 420, Puzzle 5 (Augustus Caesar).

Question is: Shutter __, Press This Button to Take a Photo

and the answer is: RELEASE

Word Meaning:

RELEASE — The event of setting (someone or something) free (e.g. hostages, slaves, prisoners, caged animals, hooked or stuck mechanisms).

Definitions from Wiktionary.