The Canon RF 600mm f/11 IS STM is an especially compact and lightweight lens considering its long focal length. Also contributing to the reduced size is a distinct optical layout, which uses gapless dual-layer diffractive optics instead of multiple heavier individual elements, which also effectively controls color fringing and chromatic aberrations for high clarity. Additionally, a Control Ring is also integrated into the lens design for intuitive control over exposure settings from the lens itself. A fixed f/11 aperture contributes to the sleek and portable form factor as well as a balanced mixture of the depth of field and sharpness. An Optical Image Stabilizer helps to minimize the appearance of camera shake by up to five stops to better enable working in low-light conditions and with slower shutter speeds.STM stepping motor offers fast, quiet, smooth, and accurate autofocus performance that is ideal for video recording as well as still shooting.