Sarah Clay tunes a grand piano Thursday at Highland Baptist Church. Clay, who has a music degree from Mississippi State University, learned to tune pianos after meeting Ken Raymond, owner of The Piano Man in Jackson, and has been his assistant for over two years. Pianos fall out of tune naturally and temperature changes and humidity are especially hard on them, she said. It takes about an hour to tune a piano that receives annual tuneups but can take half a day or longer on one that has set over a period of time. Piano tuners still use their ear but are greatly assisted by new digital technology that makes the job of tuning over 200 strings easier and faster.