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What exactly is bad about High/Max DPI? - Page 4

post #31 of 33
The only truth seems to be that as far as you can move by 1 pixel with your mouse, your DPI is fine, isn't it?

For precision, just check your inches/360 with mouse-sensitivity dot com
post #32 of 33
DPI only matters to the extent of you being able to get the sensitivity that you prefer for the application you are using.

Taken from:
http://geekhack.org/index.php?topic=53945.0
(I wrote it)

CPI (better known as DPI)
"Raising the DPI is completely against the logic of performance"
"DPI... is a translation of how many pixels I travel when I move my hand by one inch. It is only this."
~ François Morier, Senior Engineer at Logitech.

Video: http://www.youtube.com/watch?v=lc7JVjcPzL0

The reason why I added those two quotes and the video is to address a common misconception about DPI. Somehow, people associate higher levels of DPI with higher levels of accuracy. This is not correct. A higher DPI does not mean that the sensor is more accurate, and on many occasions there is even a trade off in terms of performance to attain those higher levels of DPI.

DPI itself is nothing more than a certain "count" per inch traveled. A higher DPI means a higher count for any distance the sensor travels across a surface which leads to the cursor (or reticle) on the screen traveling a larger distance. For example, when you are using a DPI of 400. That means that when you move the sensor an inch it will cover 400 pixels (ignoring any ingame or OS sensitivity settings). This means that on a 1920x1080 resolution screen, it will take 1920/400=4.8 inches of mouse-movement to travel across the entire length of the screen. Note that this also means that in some (but not all) applications perceived sensitivity by the user is lower for higher resolution screens.

In some cases, the addition of a wider variety of DPI steps can come at a cost in the sense that those DPI steps reduce the performance of the sensor. Especially when it comes to optical sensors, high DPI settings are typically not native to the sensor. Instead, the higher DPI settings are attained through a technique known as interpolation (more accurately, there are different techniques through which interpolation is attained). This does not necessarily cause an issue, but there are common problems with several firmware and implementations of this technique by manufacturers. An in depth description of the interpolation process is both beyond my knowledge and the scope of this topic. If you want to know more about interpolation, you could watch the video above, and I highly suggest you check out the overview of mouse-technology by wo1fwood linked in the bottom under references.

Sensitivity
Sensitivity describes the speed and distance of cursor movement that happens as a result of moving the sensor across a surface. A higher sensitivity means that for any sensor /mouse movement, the cursor moves faster and travels a greater distance than for a lower sensitivity.

The sensitivity that you experience in-game is usually dependent on 3 settings:
-The sensitivity setting within in the operating syste (windows sensitivity slider)
-DPI setting on the mouse
-Ingame sensitivity setting
Ingame sensitivity = [OS sensitivity setting] * [DPI setting on the mouse] * [Ingame sensitivity setting]

Many games give an option to use “raw input”. By turning this on, the OS sensitivity setting will be ignored for your ingame sensitivity. Your ingame sensitivity will then be described by: [DPI setting on the mouse] * [Ingame sensitivity setting]. However, it is not uncommon for issues to be reported with the “raw input” setting of some games. This is why people often choose the windows 6/11 setting instead without using raw input, making sure they are not exposing themselves to any specific issue the raw input setting of a particular game might cause.

A windows setting of 6/11 is the best setting, as it gives a 1 to 1 relationship between mouse and cursor movement that is not altered through software. In practice, using a windows setting below 6/11 is not too harmful. Certain minimal amounts of movement are thrown out (counts ignored), but minimal mouse movement remains 1 pixel, so there is no “skipping pixels”. Depending on the choice of windows setting, sensitivity is multiplied in the following way:
Setting 6/11 = 1
Setting 5/11 = .75
Setting 4/11 = .5
Setting 3/11 = .25

Where things start going wrong in a more noticeable and harmful way is when you choose a windows sensitivity above 6/11. This will result in skipped pixels. For example, if you wanted to do something with precision and move the cursor with one pixel, this might not be possible with a windows sensitivity setting larger than 6/11. The higher the windows sensitivity past 6/11, the more pixels are skipped. Minimal mouse-movement is no longer 1 pixel, but instead several pixels.

Regarding the G500
I once did a review on it here on OCN, since despite its issues it is still a popular mouse. The " knock" on the G500 in my experience was:
-Very heavy and weight is awkwardly distributed
-Sensor is not located in the middle but put more towards the front
-Mousewheel taken from the MX revolution. Great general consumer wheel (free-wheel, side-scroll) but wobbly mess that has no business being on a gaming mouse
-Avago 9500 has acceleration
-Testing the Avago 9500 implementation of the G500 on cloth, there seemed to be increased acceleration

That said, the Avago 9500 is not the worst sensor in the world, and people seem to like the shape. However, given that the G400(s) exists, there seems little reason to go fo rthe G500 instead.
Edited by kazuyamishima - 3/12/14 at 2:31am
post #33 of 33
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