High-impact quality keywords include: '4K,' '8K ultra HD,' 'hyper-detailed,' 'sharp focus,' 'photorealistic,' 'cinematic,' 'professional photography,' 'award-winning,' 'masterpiece,' 'high resolution,' 'intricate detail,' 'ray tracing,' 'subsurface scattering' (for skin), 'volumetric lighting,' 'depth of field,' 'shot on Canon EOS R5.' Stacking 3–5 of these at the end of your prompt consistently improves output quality. Avoid overloading with too many — pick the most relevant ones for your scene.