It has become one of the most controversial questions in cancer medicine: Can using a cell phone cause brain tumors? The federal government and the mobile-phone industry have maintained that there is ...
Most mobile phones set the 23 - 27mm focal length to 1x (1.0x). Thus, the super wide-angle is 0.4x, 0.5x, 0.6x, and the medium telephoto is 2.0x, 3.0x, 5.0x... But this brings about two basic ...