The kind of microphone you use for a piano depends on the genre and the tone.
Recording a punchy upright for a rock song? A pair of dynamic mics would work fine.
Recording a smooth grand piano for a ballad? A pair of condensers is your best friend. Whether you want them to be small or large diaphragm depends on how bassy or bright you want the piano to sound.
If you can’t figure out which to use, the rule of thumb for pianos is to lean on the side of condensers.
