tech_tonescale
This shape is something close to a hyperbola (More about this in the tonescale page).
Say we take a linear ramp left to right going from 0 to 1, and we plot it so that the pixel values are represented as height. So X-axis is pixel x position, Y-axis is pixel value.
The red dotted lines are zero and one.
Now say we multiply up the ramp so that the maximum value is 6. If we don't change the range of our plot it might look something like this.
