How far can you shoot with a 100mm lens and still get a sharp photo?

There isn’t a fixed maximum distance for sharpness with a 100mm lens. If the subject is beyond the lens’s minimum focus distance, it can be in focus.

What really affects sharpness is:

• accurate focus
• shutter speed fast enough to stop motion and camera shake
• aperture and depth of field
• how large the subject appears in the frame

For basketball, subject motion is usually the bigger issue than distance. A fast shutter speed is important; one answer suggested at least 1/125s, though indoor sports often demand even more. In dim gyms, that can be difficult without a fast lens or flash.

Distance also affects framing: the farther away you are, the smaller the player appears, so they occupy fewer pixels and may look less detailed even if technically in focus. On the baseline or sideline, a 35mm or 50mm may suit nearby action, while roughly 80–150mm works better for longer-range shots depending on whether you want full-body or tighter compositions.

So: a 100mm lens can be sharp at many distances, but for basketball the practical limits are focus, motion blur, light, and whether the subject is large enough in the frame.