There's still plenty of silver bromide left over, though.

但仍有很多的溴化银存在。

When a photon hits a crystal of silver bromide on a film strip, for instance, it knocks an electron off a negatively-charged bromide ion to create an atom of bromine.

例如，光子撞击胶卷表面的溴化银晶体时，从带负电的溴离子上“敲掉”一个电子，生成一个溴原子。