From the overwatch official forum:
Linear Ramp and Aim Curves
Tim Ford Lead Engineer
I’d like to clear up some confusion about the difference between Linear and Exponential Ramp as well as announce some new options you can leverage to fine tune your aim. I’ve read a few posts that assume Exponential Ramp yields a exponentially higher turn rate than Linear when the aim stick is fully deflected. This is a reasonable assumption, since an exponential curve will yield a higher result than a linear curve for values greater than 1. However, the goal of Exponential Ramp is to map a sensitive aim stick to a restrained aim value. We achieve this goal by mapping linear input to exponential values over the range from 0 to 1. The exponential ramp values we are concerned with fall into the region of the curve boxed in the following image:
http://imgur.com/fiGfLpIYour input is constrained from 0 to 1 where 0 is the value at the tip of the dead zone (usually about 20-25% stick deflection) and 1 is fully deflected. The dead zone is computed with the scaled radial technique explained here (
http://www.third-helix.com/2013/04/12/doing-thumbstick-dead-zones-right.html). Linear Ramp uses this value to compute your aim turn rate. Exponential Ramp scales this value (roughly) by a power of 2.5. So, a Linear Ramp input of 0.25 will map to an Exponential Ramp input of 0.03125. A Linear Ramp input of 0.75 will map to an Exponential Ramp input of 0.4871. Naturally, a Linear Ramp input of 1.0 will map to an Exponential Ramp input of 1.0. Incidentally, Exponential Ramp is “roughly” a power of 2.5 because it’s actually a hand drawn curve we borrowed from our generous friends on the Call of Duty team.
Today, we give you two choices for input curve mapping, Linear and Exponential Ramp (Dual-Zone is technically linear as well). Of course, there are a whole family of possible curves between linear and our current exponential (and beyond). In an upcoming patch, we will add an option called Aim Ease In. This is a slider option from 0 to 100 that corresponds to an exponent from 1 to 5 respectively. Combined with Linear Ramp, this option will allow you to select a wide range of curves to map your aim input to your taste.
http://imgur.com/MzZZKNLAim Ease In is compatible with Exponential Ramp and Dual Zone, although you should expect a fairly compressed aim curve if you crank this option with Exponential Ramp.
Link:
https://us.battle.net/forums/en/overwatch/topic/20758657839?page=1