Putting a piece of tape over half the sensor is a good way to decrease lift-off distance.
Verdict: False. While this technically works, it’s not a good idea, as it affects the sensor’s performance.
Lift-off distance is the point at which a mouse stops reading the surface below it. For a select group of gamers who play at low sensitivity settings (often in old games like Counter-Strike 1.6), low lift-off distance is important, because they’re often picking the mouse up and moving it to the other side of the pad. If lift-off distance is too high, the sensor will keep reading the surface as it’s being lifted, resulting in unwanted cursor movement. One homebrew solution is to place tape over part of the sensor.
Morier: “[The tape] is masking part of the light that comes from the LED. You are shortening the time when you lift that this LED will see a spot that is crossing the surface. If you put the tape … [the LED will reach that spot] much faster and provide the lift early. Then you have the feeling that, ‘Yay, I improved the lift!’ But in fact you improved the lift but degrade the maximum speed very often. Because having only half of the matrix or part of the matrix that is correctly illuminated will prevent you from having good high speed tracking. It will not that much affect the low speed but it will clearly kill the high speed on some surfaces. It’s a trade-off. If the guys are happy with that, maybe they’re not a very high speed player and can bear with this. But really it’s a trade-off.”
Today, several mouse companies offer surface calibration features that adjust the mouse to the surface below it, and then offer an adjustable lift-off distance. Using that feature is better than using a piece of tape, because it preserves high speed tracking performance. And high-lift off distances are typically the result of mouse makers having to choose a generic setting that will preserve sensor reading on a variety of surface colors and textures. With surface calibration, there’s no need for that generic setting, often allowing for very low custom-set lift-off distances.