I was doing a search, and found that the need to sharpen digital images comes from the manufacturing of the digital sensors.
It seems that the pixel sensors are disposed in a RGB pattern, and as such, the R sensor does not know what the G or B information is exactly at that spot, and it must be interpolated.
The question is: the Foveon X3 sensor wouldn't need less or no sharpening? Someone used a camera with this sensor, such as the Sigma SD9 or SD10?