Use prompts that specify professional photography terms: 'portrait photography, studio lighting, sharp focus, symmetrical face, high detail.' Add camera details like '85mm lens, f/2.0 aperture' to signal a portrait shot. Avoid extreme angles or unusual perspectives for faces. If distortion persists, try adding 'professional headshot, editorial quality, no distortion' and use the Nano Banana Pro model for higher fidelity facial rendering.