It is fairly difficult to convey the responsiveness and precision of mice due to the complex nature of measuring the true arbitrary values and how they may are manipulated with onboard processing or software. Responsiveness can be effected by various things such as the sensor type, refresh/polling rate, but also by the connection interface (older/lower end systems can suffer from overloaded USB ports or USB interference), software/firmware, and what type of MCU (micro-controller unit) is being used. Mice that feature a micro-controller can sometimes muddy the water as they can potentially have a positive or negative effect depending on how fast it can calculate or predict the motion being input. Though, in most scenarios, mice using the same sensor tend to perform within a fair margin of each other. Though there are times this can be called into question depending on how various aspects surrounding the sensor are implemented (firmeware/software/MCU.
There are some other observable issues that can be easier to explain in a visual manner.
Stutter
This is often caused by a faulty MCU, firmware and/or USB interference. What happens is, there are random lockups/freezes in the reporting of the mouse causing stuttering. This can range from mild to extreme and is usually a sign of a faulty mouse, or a bug within the firmware.
This image displays a fairly mild stutter which was caused a buggy pre-release firmware where the memory cache of the mouse's MCU wasn't dumping/refreshing correctly. By scribbling circles in MS Paint, the point when there was a stutter/freeze you can notice an angular/ unnatural change in direction (there are more instances observed than highlighted, but the point remains the same).
Jitter
Jitter is something we have been looking at a fair bit and any FPS fan may experience the jitters at some point once they pick up that sniper rifle. Why did the mouse move up a pixel, or even worse, LEFT when you moved right? So what is Jitter? The best thing to compare it to would be 'noise' in photography. Let's assume that you wish to draw a line from left to right, the sensor will effectively try to predict the best line of travel from A to B. Along the way, the sensor will pick up imperfections in the travel either because the sensor is either too sensitive, or not sensitive enough, and thus it will then fill in the difference by choosing which pixel next best represents the most likely path. An increase in sensitivity may cause an increase in 'noise' causing the mouse cursor to jump in an undesired direction and is often visualised by 'staircasing' in MS Paint. A small amount of jitter can be expected in most sensors and it tends to increase with a higher resolution (DPI), especially if the sensor is interpolated (a method to expand the DPI artificially).
This image here shows a side by side comparison of a Corsair mouse that was experiencing a problem with its interpolation vs the Razer Mamba TE. From left to right the DPI settings were each at 9000/6000/4000/1800/800. For the faulty Corsair mouse, the reasonable level of jitter would be from 4000DPI and less, though ideally, none at all is preferred. It is worth mentioning that jitter can have a much stronger effect on low resolution screens where movement from pixel to pixel would be much more noticeable as there would be an amplification of the inaccuracy caused by the jitter.
Jitter isn't only a sensor specific issue, but can also be caused by the sensor lens, the MCU, the firmware/software drivers and overall implementation. A good example of this would be the comparison of the recently viewed Cooler Master Mastermouse PRO L and the Speedlink OMNIVI, both of which are using the Pixart 3360 optical sensor.
As you can see, the CM MM PRO L features a steady amount of jitter throughout its entire DPI range, getting rather unreasonable at 12K DPI, while the Speedlink OMNIVI that features the same sensor only starts displaying a small amount of jitter at its maximum DPI and so judging a mouse on sensor alone isn't always the best idea.
There are some other problems that mice experience such as 'lag' which is often caused by a system with saturated memory, or a game that isn't dumping memory properly, though if there is no explainable cause for it, then the mouse is likely just faulty.
Sensor Types
There are two main types of sensors in use today, each using a similar kind of technology. They shine a light and track the movement. Some use laser others use LEDs. Lasers are renowned for their high precision, high acceleration, and often have the advantage of being able to track no matter the surface. LEDs (often referred to as optical) historically struggled on various surfaces and often moved rather sluggishly. People often debate which is better between laser and optical sensors, but the truth is, lasers have a technical advantage, but tend to be too much for the needs of a mouse and suffer from 'hardware acceleration' which translates to 'the faster you move your mouse, the farther the cursor will travel'. Even when you manually set acceleration to be OFF on your laser mouse, there is still around 5% acceleration in effect, while optical sensors can have 0 acceleration, providing higher reliability, predictability and in-game accuracy. Optical sensors also have come leaps and bounds in that past few years with the 3360/3366 sensors leading the way, it seems laser sensors may take a backseat for a while with exception to the Phillips TwinEye lasers used by Razer.
Regardless of sensor type, both kinds can suffer from the above listed problems.
There are some other observable issues that can be easier to explain in a visual manner.
Stutter
This is often caused by a faulty MCU, firmware and/or USB interference. What happens is, there are random lockups/freezes in the reporting of the mouse causing stuttering. This can range from mild to extreme and is usually a sign of a faulty mouse, or a bug within the firmware.
This image displays a fairly mild stutter which was caused a buggy pre-release firmware where the memory cache of the mouse's MCU wasn't dumping/refreshing correctly. By scribbling circles in MS Paint, the point when there was a stutter/freeze you can notice an angular/ unnatural change in direction (there are more instances observed than highlighted, but the point remains the same).
Jitter
Jitter is something we have been looking at a fair bit and any FPS fan may experience the jitters at some point once they pick up that sniper rifle. Why did the mouse move up a pixel, or even worse, LEFT when you moved right? So what is Jitter? The best thing to compare it to would be 'noise' in photography. Let's assume that you wish to draw a line from left to right, the sensor will effectively try to predict the best line of travel from A to B. Along the way, the sensor will pick up imperfections in the travel either because the sensor is either too sensitive, or not sensitive enough, and thus it will then fill in the difference by choosing which pixel next best represents the most likely path. An increase in sensitivity may cause an increase in 'noise' causing the mouse cursor to jump in an undesired direction and is often visualised by 'staircasing' in MS Paint. A small amount of jitter can be expected in most sensors and it tends to increase with a higher resolution (DPI), especially if the sensor is interpolated (a method to expand the DPI artificially).
This image here shows a side by side comparison of a Corsair mouse that was experiencing a problem with its interpolation vs the Razer Mamba TE. From left to right the DPI settings were each at 9000/6000/4000/1800/800. For the faulty Corsair mouse, the reasonable level of jitter would be from 4000DPI and less, though ideally, none at all is preferred. It is worth mentioning that jitter can have a much stronger effect on low resolution screens where movement from pixel to pixel would be much more noticeable as there would be an amplification of the inaccuracy caused by the jitter.
Jitter isn't only a sensor specific issue, but can also be caused by the sensor lens, the MCU, the firmware/software drivers and overall implementation. A good example of this would be the comparison of the recently viewed Cooler Master Mastermouse PRO L and the Speedlink OMNIVI, both of which are using the Pixart 3360 optical sensor.
As you can see, the CM MM PRO L features a steady amount of jitter throughout its entire DPI range, getting rather unreasonable at 12K DPI, while the Speedlink OMNIVI that features the same sensor only starts displaying a small amount of jitter at its maximum DPI and so judging a mouse on sensor alone isn't always the best idea.
There are some other problems that mice experience such as 'lag' which is often caused by a system with saturated memory, or a game that isn't dumping memory properly, though if there is no explainable cause for it, then the mouse is likely just faulty.
Sensor Types
There are two main types of sensors in use today, each using a similar kind of technology. They shine a light and track the movement. Some use laser others use LEDs. Lasers are renowned for their high precision, high acceleration, and often have the advantage of being able to track no matter the surface. LEDs (often referred to as optical) historically struggled on various surfaces and often moved rather sluggishly. People often debate which is better between laser and optical sensors, but the truth is, lasers have a technical advantage, but tend to be too much for the needs of a mouse and suffer from 'hardware acceleration' which translates to 'the faster you move your mouse, the farther the cursor will travel'. Even when you manually set acceleration to be OFF on your laser mouse, there is still around 5% acceleration in effect, while optical sensors can have 0 acceleration, providing higher reliability, predictability and in-game accuracy. Optical sensors also have come leaps and bounds in that past few years with the 3360/3366 sensors leading the way, it seems laser sensors may take a backseat for a while with exception to the Phillips TwinEye lasers used by Razer.
Regardless of sensor type, both kinds can suffer from the above listed problems.
