The actor, 55, began filming his first series as The Doctor this week following a brief appearance in the Christmas Day edition.
In an interview with Doctor Who Magazine, Capaldi said: "People look at (the old shows) and, understandably, mock the bargain-basement monsters, and the accidents and collisions.
"But those old shows were only made to be watched once, on a flickering monochrome telly that smelled of valves and furniture polish. In that context, they succeeded immeasurably. They were triumphs of imagination."