The title of the puzzle alludes to the fact that each of these is a picture with only one half reflected down the middle. This clues that each of these pictures represents a word or phrase that contains a palindrome. Below are all of the answers with the palindromes in capital letters.
Each palindrome has a central letter or repeated central letter, depending on if it is an odd- or even-length word. Reading the central letters of each palindrome in order, you get PALINDROMIC SEVEN LETTER AUTO which clues RACECAR or RACE CAR.