Common skin warts (also called cutaneous warts) are raised round or oval growths. A wart may be lighter or darker than the skin around it. Some warts may have tiny black dots in them, often called seeds. The dots are small, clotted blood vessels. Warts may occur alone or in larger groups that merge and form patches.
According to Canon (link):  Canon addressed the âfeedback loopâ in later model IS lenses by introducing an algorithm to the IS detection system to automatically recognise when the lens is mounted to a tripod.
As with the Canon SL1's Hybrid CMOS AF II system, the new Dual Pixel CMOS AF in the 70D system utilizes an extremely large area of the sensor for autofocusing, as shown in the illustration below. In fact, 64% of the total area of the sensor (80% of the frame, vertically and horizontally) can be used for phase-detect AF.