Nice, I'll update it tomorrow! As for the accuracy, note that the in-game slider is off, you need to use the config file for it to be accurate. As this is Unreal Engine 4 it might also be a smoothing issues, I'll check when I update.
Both are right in their own respect. Because the horizontal FOV is different it's only possible to match one of them, so it's down to what you want here; The same tracking speed (MDH 0%) or the same flick distance to the edge of the monitor (MDH 100%).
You should try to match the hipfire FOV if possible, the ADS and scopes you usually can't do anything about (with some exceptions).
Make sure the Actual FOV is the same.
Tested it now, and from what I can gather:
The value is completely ignored if you turn off smoothing in-game.
If smoothing is on in-game, then:
0 - No smoothing
1 - No smoothing
2 - Some smoothing
3 - More smoothing
Higher values seem to revert to either 1 or 2.
Lower framerates equal more smoothing, so most likely these values are how many frames the movement is smoothed over.
It only affects how much the ADS zooms, technically the sensitivity will scale according to your settings so it should remain the same.
In short you will get more zoom with it off if your FOV is higher than 55, so it depends on what you want.
I've added support for this now. The ADS FOV actually doesn't zoom at all, it just moves the camera slightly.
The calculator will now use the original ADS FOV if the FOV is default (75) and set it to the hipfire FOV if you change it to any other value.
You should be fine just entering your data and leaving everything else default: https://www.mouse-sensitivity.com/?share=9fd5d75149a9c2e3c5816ff4b8b08cdc
These control how the sensitivity for each aim is converted, and ideally ADS and scope should be set up to match the settings in the game you are converting from. This can be a bit complicated though, as some games doesn't have straight forward scaling of ADS like for instance Black Ops 4, where the Monitor Distance Coefficient is the Monitor Distance and the High and Low multipliers are the scale.
If both Widowmaker and Ana are default, like this: https://www.mouse-sensitivity.com/?share=6e358c267412d0f468951abc0148e949
Widowmaker 40 like this: https://www.mouse-sensitivity.com/?share=9d53198860a9b1946f113f0418d617f6
You have to both use a low polling rate and disable smoothing in the config file to get correct sensitivity in this game, check the notes!
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If the FOV is locked in the game I can't measure how potentially changing it affects the sensitivity, so there is no way to do this accurately. If the game has a locked FOV but there is a mod or something that allows for FOV change I need to analyze it first.