If there was an abrupt and complete absence of light, you would likely notice it immediately. Humans are highly sensitive to changes in their visual environment, and the sudden absence of light would be quite noticeable.
Our eyes are designed to detect light and send signals to the brain, allowing us to perceive our surroundings. When light is present, it interacts with objects, and some of it is reflected into our eyes, forming an image. If all sources of light suddenly disappeared, the environment would become completely dark.
In such a scenario, you would immediately perceive the absence of light as a drastic change in your visual perception. The transition from a lit environment to complete darkness would be startling and noticeable, and you would likely be able to perceive the difference right away.
However, it's important to note that in some cases, the absence of light may not be immediately noticeable. For example, if you were in a very bright environment and the light slowly faded over time, it might take a little while for your eyes to adjust and for you to fully realize that the light had disappeared. But in general, if there was a sudden and complete absence of light, you would likely notice it immediately.