Often actual mouse dpi is not exactly what's claimed. A 400 dpi mouse could be 380 or 420.

Another possibility, if you feel like you're experiencing inconsistency in game, is the dreaded (and mysterious) sens bug. I know for a fact some type of "sens bug" did exist at one point in time, because I've measured before and after in_restart and noted a difference when I thought something was off.

420 DPI )

http://www.funender.com/quake/mouse/index.html

Try this see if its more accurate. My g303 says its on 1100 dpi but it actually works out at 1150 when I measure myself. Not sure if anyone else has found the same thing with the g303 though

Only raw mode ( in_mouse 2 ) shouldn't be effected by windows driver settings, but even then some mouse manufacturers' drivers seem to mess with this, it's like their sensitivity options are actually altering CPI but it's not documented what they're actually doing anywhere (logitec, and iirc razer have this issue)

Next thing is m_pitch (verticle motion) and m_yaw (horizontal) will change things too

Finally of course if cl_mouseAccel is not 0 then any measurement is basically meaningless as it's entirely dependent on the exact speed you are moving the mouse.

oh it will also be off if you happen to be playing with +zoom enabled constantly, so cg_fov and cg_zoomfov swapped over, like noctis.

I'm using abyssus 2k14 now. With my A4Tech X-718BK it's the same.
When reality is 20.18 cm/360, mouse-sensitivity.com tells me it's 17.3182 cm.
Same on win7 and win10.
MarkC mouse fix applied on both.
6/11 win.
No accelerations of any kind and trying to use rawiput in every game.

And the same effect in source games (css, csgo, hl2).

More than a decade ago, during the ancient times of WMOs and MX300s, a friend and I wondered on a lan, why the same mouse (2 identical models), configuration values, mousepad and computer gave us completely different [cm/fullturn] results.
I then contacted the manufacturer and got a stunning answer:
The values given on the box/driver are actually just approximations, due to manufacturing tolerances of the lens curvature and of the geometrical positions for internal parts like lens and sensor, the true dpi value can be anywhere within a +/-20[%] margin of the given value.
For this reason, it is total nonsense to take a pro player's values for sensitivity, m_yaw, windows-multiplier and dpi, in order to precisely calculate his 30.0123456789[cm/fullturn], while his true value could be anywhere within the range of 24...36[cm/fullturn].

This is a systematic error and will have the same percental offset on all dpi values you set in the driver for a specific mouse.
But when switching mice the most precise method of measuring that consistent dpi offset I found so far is:
1)
Borrow some "Lego Technic" parts from your nephew to build a guiding frame that prevents vertical components of mouse movement influencing the measurement.
2)
Measure the highest distance available on your mousepad.
(A measuring error of 1mm due to observation parallax, is 1% when you measure on a low distance like 100mm, but only 0.1% when you measure on a high distance like 1000mm.)
3)
Recalculate your true dpi and out of it the systematic percental offset that will apply to all your dpi values on this specific mouse.
When you know the systematic error you can then recalculate the sensitivity you have to use for your desired [cm/fullturn] with whatever dpi you prefer on this specific mouse.

Thanks for reply, bro. Really informative and interesting.
So the rightest way to get YOUR OWN sens is to measure it in cm/360 always and trying to get the same with a ruler every time if you changed your setup.

Unfortunately yes, even when it sounds medieval, the ruler method is more accurate than blindly trusting calculations based on approximated +/-20[%] dpi values.

Just imagine your mouse (A) is on the upper end of the tolerance spectrum (120%) and your mouse (B) is on the lower end (80%).
When you change mice then the relative errors are:
Changing from (A):=100% to (B) -> -33% sensitivity error.
Changing from (B):=100% to (A) -> +50% sensitivity error.

But I assume that since then, the build quality and reproduction stability has improved, because for some years the highest offset I found on a mouse was +11.2% (G400) and my current offset is +7.5% (G400s).

7.5% is anyway too much. If it would be like 1% it would be acceptable but anyway may be noticeable.
So I think ruler is the best way. How blind I was without this knowledge..
Now I feel myself like a kid, comparing sens to sens (ingame, w/o considering mice dpi, win sens, accel and stuff) XD

Quality... hah. OMG, how many things are shit now. I can't buy a 144Hz monitor (2 moneybacks already) I can't get a decent pair of studio monitors (2 pairs were defective), I've got descend smartphone only from 2nd attempt, I've got non-defective Razer mouse from 2nd attempt. WTF is wrong with this world.
I think I should wright about it..

A +7.5% (or even +136346%) offset is not a big problem, because you can measure it, take into account that systematic offset and still apply all those transformation calculations with 107.5% of your driver/box dpi (your_true_dpi=1.075*driver_value).
If your hardware would have infinite quality/precision, you weren't able to blame it for missing shots >:).

great.
why didnt you tell it last year when new mouse and dpi math fucked my sens and accel?

why you need lego frame? vertical movement shouldnt matter.

>why you need lego frame?
To move your mouse EXACTLY straight line w/o any deviations.
But you can do that w/o lego frame, it just would be a bit harder to do.

To be honest, I'm actually just telling it because I have to quit QL due to the birth of my son in February.
Otherwise I would enjoy another decade of finest esr-comedy from people wondering why mice switching makes their aim feel off or how they copy a pro player's sensitivity based on his dpi:
http://www.esreality.com/post/2783287/another...pid2783636

Second question is a prefect opportunity to recycle a sketch I created to explain it to my brother, but I can't find it right now and have to leave, I will search it in the evening.
The guiding frame has basically 2 major tasks, it guides the mouse on a straight line to make the measurement of the distance easier (clerictgm's Comment #13) and it fixates the mouse in a orthogonal orientation to prevent measurement errors from mouse rotation (NCL Pharton's Comment #16).



EDIT:



a)
The left picture shows that having a vertical movement of the mouse on the mousepad affects your measurement due to observation parallax, so it is better to move the mouse on a straight line.

b)
The upper right picture shows how a rotated mouse causes a vertical movement of the crosshair/cursor ingame and what it means for your measurement due to trigonometry:
I rotate my mouse by an angle of 30° clockwise and measure a horizontal movement on a straight line to the right of 100mm distance.
What the mouse sees in its relative sensor-bound x- and y-axis are
a horizontal movement component in the x-axis of 100mm*cos(30°)=87mm
and
a vertical movement component in the y-axis of 100mm*sin(30°)=50mm.
So a vertical crosshair movement ingame indicates that my mouse is in a rotated status and although I moved it 100mm horizontally on a straight line on my mousepad, the mouse saw a smaller horizontal movement of 87mm in its x-axis, so my measurement/calculation will be wrong by 13%.
Simple experiment:
Rotate your mouse and move it on a straight line to a side, you will see the cursor/crosshair perform a vertical movement.

c)
The lower right picture is just an explanation why the highest sensor trajectory on a mousepad is mousepad-width minus mouse-width, not relevant here.

If you don't have access to "Lego Technic" parts, you can use a rigid beam on the bottom of the mouse to guide it on a straight line and watch the crosshair/cursor to detect if it moves vertically, which means mouse rotation and therefore an inaccurate measurement.

adjust m_cpi until it alligns with the correct cm/360 value, the value of cpi you stop on will be a close approximation of your true cpi on your given setup (mouse/mousepad)