Does the L50 get confused holding it to close to the ceiling. ie; looking for studs above a window close to the ceilling?

Hello Keith. The reason the L50 may be getting erratic readings above a window is because in residential building there is usually a solid piece of wood called a header above windows and door ways and StudSensors cannot calibrate through solid surfaces deeper than 1 1/2". Headers are usually made of 4"x12" wood. Hope this answers your question. Thank you.