低调光胡须男性肖像

生成一张 4:5 竖版低调光胡须男性肖像。中国 40 岁左右留短胡须男性，穿黑色粗针织毛衣，站在纯黑背景前的窄光区，身体侧向右方，脸部三分之二侧面，双手自然握着一只无字黑色陶杯。主光是一条从右侧切入的窄条形硬光，只照亮鼻梁、胡须边缘、手部和杯口，另一侧落入深阴影但保留轮廓。真实低调棚拍摄影，90mm 镜头，胸像构图，皮肤与胡须纹理清晰，人物比例真实。画面内不要出现任何可读文字、logo、水印、杯身标记或品牌标识。

Create a 4:5 vertical low-key bearded male portrait. A Chinese man around 40 with a short beard wears a black chunky knit sweater and stands in a narrow pool of light against a pure black background. His body turns to the right with a three-quarter side profile, and both hands naturally hold a blank black ceramic cup. The key light is a narrow hard strip from the right, illuminating only the bridge of the nose, beard edge, hands, and cup rim, while the other side falls into deep shadow with a retained outline. Real low-key studio photography, 90mm lens, bust composition, clear skin and beard texture, realistic proportions. No readable text, logo, watermark, cup mark, or brand mark anywhere in the image.