Top 5 features of Canon A-1 Film SLR : 1. **Aperture-Priority and Shutter-Priority Modes:** The Canon A-1 was one of the first cameras to offer both aperture-priority and shutter-priority exposure modes, giving photographers greater control over their shots. 2. **Programmed Auto Exposure (AE):** The A-1 featured a sophisticated programmed AE mode, allowing the camera to automatically set both aperture and shutter speed for optimal exposure, making it user-friendly. 3. **Interchangeable FD Lenses