Sigma launches new ART versions of their 30mm and 19mm f2.8 and new 60mm f2.8 lenses

Most lenses have more issues with aberrations away from the center of the lens. Optical stabilization pushes light paths of those edges in toward the center of the sensor as the camera bounces around. Resolution also drops toward the edges so you have a little of that impacting the image on the sensor as well. How much this impacts a sensor I don't know, but it is there to be noted.

Thank you
Russell