Besides setting your overall sensitivity with “set sensitivity” you can do some fine tuning. With tweaking the variables m_pitch (vertical [up/down]-sensitivity) and m_yaw (horizontal [left/right]-sensitivity) in your configuration, you can effectively improve your aiming for getting more headshots.

How do m_pitch and m_yaw work?

As the author of the rtcw.jolt.co.uk-article points out correctly: illustrations may be the easiest way to describe the effect of a.) sensitivity, b.) m_pitch and c.) m_yaw:

Note those are just illustrations to visualize that you can squeeze your mouse-responsiveness vertically and horizontally using m_pitch and m_yaw.

How does the game engine translate your mouse-movement?

As ruffnux points out in his acceleration-bug-report, every “count of frames” times per second the mousemovement is calculated like (1.) mouseX * sensitivity * m_pitch and (2.) mouseY * sensitivity * m_yaw. The default setting for m_pitch and m_yaw is 0.022. Now if you lower m_pitch or m_yaw, you get an ellipse instead of a circle for your vertical or horizontal mousemovement. So with lower m_pitch it will be easier for you to keep your cross-hair at head level. But as always: no pain, no gain, as on the other hand it will be more difficult to aim up and down (e. g. for compensating your cross-hair going down when crouching or proning or to aim at someone on a balcony or stuff like that).

How do I set up m_pitch and m_yaw?

Both settings depend on each other. As a rule of thumb ruffnux suggests to ensure m_pitch is at least 2/3 of what m_yaw is set to. So e. g. if you leave m_yaw at the standard setting of 0.022, set m_pitch to 0.66 * 0.022 = 0.015. Most servers will anyway include punkbuster-restrictions, that where introduced by clanbase at RTCW back in 2003. The reasons was to avoid players locking their cross-hairs to headshot height and so demanding more aiming skills. After restricting m_pitch to a range also m_yaw had to be set to a fixed range or value to achieve this goal. The reason is because you can also achieve a lower vertical responsiveness by (1) lowering your overall sensitivity and (2) compensating that by increasing your vertical responsiveness again with m_yaw to get back your original vertical sensitivity. The restrictions

pb_sv_cvar m_pitch out -0.015 0.015
pb_sv_cvar m_yaw in 0.022 or pb_sv_cvar m_yaw out -0.022 0.022

This means your minimum values on punkbuster-servers can be 0.015 for m_pitch and 0.022 for m_yaw. So on punkbuster-servers those values should be set up to:

set m_yaw 0.022
set m_pitch 0.01501

Are there other ways to tweak my vertical responsiveness?

Yes there are other ways. For example some mouse-drivers (Razer) will let you adjust your vertical and horizontal mouse responsiveness. Using some configuration hacks It was also possible for Logitech users in the past to use Razer-drivers with Logitech mice (see e. g. this article on Crossfire [thanks to oBs for the hint], “Razer Drivers with Logitech” on ESR or this guide):

Is this still possible – anyone tried it out?

Poll:

When your mouse pointer flickers or doesn’t run smoothly, maybe the refresh rate of your mouse it set too low…

What’s the mouserate?

To be able to move your mouse cursor on screen of course your operating system has got to know the mouse has been moved by you on the mouse-pad. This is done by polling the mouse for any input at the device it is plugged in. Basically you can use the standard PS/2- or an USB-port to plug in your mouse. PS/2 comes with a standard polling rate of 80hz (adjustable from 20 hz to 200 hz). USB comes up with a standard polling rate of 125hz (overclockable to 250hz, 500hz and 1000hz). Depending on your setup, you force your mouse to send data via PS/2 or USB to your operating system every 8 ms (= 125hz), 4 ms (= 250hz), 2 ms (= 500hz) and so on…

What’s the positive effect of a higher mouserate?

Your cross-hair may move more smoothly the higher the polling rate is set up. You will feel the difference from 125hz to 500hz. But you probably won’t feel any more difference between 500hz and 1000hz. A smooth mousemovement is essential in Wolfenstein: Enemy Territory, as you need to be able to aim precisely, you need to be able to target fast and you got to avoid any erratic movements. Sometimes it is just the little 1 ms of reaction time that is missing due to imperfect hardware setup and that thus makes you lose a duel. So you should set it up to 200 hz (PS/2) or 500hz (USB) if you don’t witness any of the possible disadvantages (USB) – like I do …

Any risks of a tweaking the USB-polling-rate?

Yes – there may be some! First: the higher the USB-polling rate, the higher your cpu-usage will be. Depending on your hardware this increase can be massive for each usb-device that is excessively refreshing data at high frequency. Further more common risks in combination with overclocking your USB-polling rate are damages to your hardware (e. g. your mainboard or your usb-peripherals such as your mouse if it can’t handle the higher polling rate) or stability issues with your pc. Tweak on your own risk!

How do I raise the polling rates?

PS/2 settings from RaZiel

To tweak your USB-ports use UsbRate v0.5 from RaZiel (download). Make sure you disable the realtime feature as it may crash your pc.

To tweak your PS/2-port go into your mouse-properties menu or use the PS2Rate-Tool (download) and adjust it like the thumbnail shows.

Reboot to let the changes take effect.

How do I test the changes?

Use mouserate.exe from Oliver Tscherwitschke (download) to measure your actual polling rate. To do this, move your mouse around in circles and watch the output. Ideally the measures are constant or at least not changing massively each poll. This would eventually damage your mouse and besides it would not support a smooth aiming.

So… in the end?

Don’t expect to be able to boost your aiming skills by adjusting the polling rate. But this is just one of many stones in the mosaic you can use for little improvement. I personally use a Logitech MX 518 mouse via the PS/2 port. The samplingrate is set up to 200hz with input buffer length 100. RaZiel suggested an input buffer length of 300 (see thumbnail from Aiming By RaZiel-Tutorial). I tried out USB at 500hz once but it ate just too many of my cpu-resources plus it seemed I did not to get a stable polling rate, so I got back to PS/2 again with which I played for many years… and it still works fine for me.

Poll: