Sony has officially announced the Alpha a7c, a full-frame mirrorless camera. Sony claims that the Alpha a7c is the world’s smallest and lightest full-frame mirrorless camera with its compact design and its 24.2MP 35mm full-frame back-illuminated Exmor R™ CMOS sensor and BIONZ X™ image processing engine. The Sony Alpha a7c will be available later this October and will be sold for approximately $1,799.99 USD. Sony also announced a new FE 28-60mm F4-5.6 zoom lens which…