You arrive at the venue shortly before the match starts. Outside there is daylight; inside there is artificial lighting. The table is ready, the balls look the same, and nothing seems “wrong”.
Yet something does not feel right from the first few shots.
Distances are not clear. Thin cuts feel more demanding. Execution is slightly unstable, without an identifiable technical error.
This is not anxiety or a concentration issue. The visual system needs time to adapt to changes in brightness and type of light. Until that adjustment is complete, depth and contrast perception are reduced, even if you feel you can “see perfectly well”. Visual physiology describes this as light adaptation, a phenomenon systematically studied as early as the nineteenth century by Jan Evangelista Purkyně and a basic principle of visual neurophysiology.
The body is present. The eyes are not there yet.
That is why being at the venue about half an hour before the match is not a warm-up. It is not analysis or work on your game. It is time for the visual system to synchronise with the venue's lighting before you ask it for precision.
When you start playing after that adaptation is complete, execution does not improve because you “tried harder”. It becomes clearer because the system doing the seeing arrived at the match in time.
If you find this useful, keep it. If not, move on.