Sigma, un nuovo aggiornamento sul Foveon (Parte 2)

“ Unencumbered by a low-pass filter Another thing: color filter arrays are prone to false color patterns (moiré). This problem is caused by interference between repeating patterns of fine lines in the subject and the mosaic pattern of the color filter array itself. Moiré is typically prevented by installing a low-pass filter in front of the image sensor. A low-pass filter works by removing the higher frequencies of light that carry fine detail. This does prevent interference and, therefore moiré. But it also adversely affects resolution and image sharpness. Facing this tradeoff, some cameras use CFA sensors without a low-pass filter, accepting the inevitable color moiré
patterns as the price to pay for a sharper image. Sigma's direct image sensor design doesn't use color filters, so it doesn't need a low-pass filter to prevent the false colors of moiré. The direct image sensor captures the sharp image formed by the lens without losing any information. As a leading lens maker with uncompromising
standards of photographic image quality, Sigma believes the ideal capture system is one that receives full color information at each and every pixel location „