I read a book "Canon EOS Rebel T5i/700D For Dummies", which warns against switching auto-focus on/off while the camera is on. I've read some tutorials and I already know how ... Canon's EOS Rebel SL3 / EOS 250D is the latest in the company's line of diminutive DSLRs. These are One-Shot AF (Canon)/Single-Servo AF (Nikon), and AI Servo AF (Canon)/Continuous-Servo AF (Nikon). Julie Adair King has been covering digital cameras and photography for over a decade. So switch it off. When the serial number displays on the screen, select âOKâ. As its name implies, Quick mode is the fastest Live View autofocusing option. Press the