0.173 sensitivity @ 1600dpi on 60g to 77g.

Formula:
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OK, this is just something I had an idea about today and I tried to run some numbers to see if it would be any good.

Background: My usual mouse which I have been using for around 1/2 years is about 85 grams (without cable) and the sensitivity which I fine tuned on it and felt was the best for me was about 1.625 at 400 dpi.

For past two days I was testing a new mouse, the roccat lua. The weight of this mouse is about 70 grams without cable. When I started playing with this mouse my usual sensitivity felt quite fast and a little hard to control.

So I experimented for several hours with many sensitivities and lowering or increasing the sensitivities by just 0.01 . After many hours of trying to find the perfect sense on the new mouse and testing in deathmatch, with botz and actual games, I arrived at a sense of about 1.35.

Then I went to sleep. But just when I was about to sleep, an idea struck me what if you find sensitivity per gram of weight. And adjust your old sensitivity in accordance with the weight difference, I was really interested to find what value would this method yield and how much it would differ from the value I found by hours of trial and error and experimentation. But I was too sleepy to do this simple calculation and fell asleep.

So when I woke up, I tested this:

So here are the calculations: Weight of mouse: 85 grams Sensitivity: 1.625 Sensitivity per gram of weight: 1.625 / 85 = .0191 (correct to 4 decimal place). Weight difference between old and new mouse: 85 - 70 = 15 grams

The weight of the new mouse is lighter so by common sense and principles of physics an equivalent amount of force, will create greater acceleration in the lighter mouse (Force = Mass * Acceleration),

Therefore the sensitivity needs to be lowered in the new mouse. But by what amount? Sensitivity per gram is .0191 and the difference in weight is 15 gram. So by basic arithmetic: The change in sensitivity should be 15 * .0191 = .2865 and this should be a reduction as discussed before. So new adjusted sensitivity = 1.3385 or 1.34 (correct to two decimal places)

But what was the sensitivity I found through experimentation and trial and error yesterday? Quite surprisingly, it was 1.35 and this felt very close to perfect. So the formula was off by just 0.01 . Either I was extremely lucky, or it was just some weird coincidence that the two values matched or this method has a robust logic and reasoning behind it.

How to explain the 0.01 error. There can be many sources of error:

Human error in trial and error method which by definition is not precise

Slight differences in advertised weights and actual weights of the mice and even small differences in weight of the cables which can add to playing weight

Differences in actual dpi and advertised dpi of the mice

Does not account for size of the mouse, argument being a smaller mice may be easier to move around faster, from a purely mechanical perspective, as perhaps a smaller size feels more nimble and provides a more sturdy grip?

Closing comments: All values were normalized to 400 dpi for simplification purposes. The lua was used at 500 dpi in practice.

This method is by no means the be all and end all and probably fraught with errors and factors I did not consider. However, as a rough rule of thumb to arrive at a ball park value, it seems to offer a lot of utility and perhaps also saves valuable time.

Very small changes can then be made to this value to further fine tune the sensitivity while using in game playing time and human judgment as a guide to what feels just about right.

Hope this may be useful for someone. Thank you.
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