Canon Ultrasonic EF100-400mm f 4.5-5.6L IS II USM Instruction Manual

To enable Image Stabilization, locate the IS switch on the side of the lens and slide it to the 'ON' position. This feature helps reduce camera shake, especially in low-light conditions or when using slower shutter speeds.
To clean the lens, use a blower to remove loose dust and a microfiber cloth for the lens elements. For stubborn smudges, use lens cleaning solution applied to the cloth. Avoid using harsh chemicals or rough materials that could scratch the lens.
To reduce lens flare, attach the lens hood provided with the lens. This helps block stray light from entering the lens. Additionally, avoid shooting directly into strong light sources.
First, ensure the lens is set to AF mode using the AF/MF switch. Check for any obstructions on the lens contacts and clean them if necessary. If the problem persists, try attaching the lens to a different camera body to rule out camera issues.
Yes, the Canon EF100-400mm lens is compatible with Canon EF 1.4x and 2x teleconverters. However, using teleconverters may affect autofocus speed and aperture. Ensure your camera is compatible with the effective aperture.
Use the focus limiter switch on the lens barrel to choose between different focusing ranges, such as full range or a limited range, to reduce autofocus time and increase speed.
Regularly clean the lens and contacts, store it in a dry place, and use a protective filter. Periodically check for firmware updates and consider professional maintenance every few years.
For optimal sharpness, use a sturdy tripod and avoid using the lens at its maximum aperture. Stopping down slightly can increase sharpness. Also, ensure proper focus settings and use Image Stabilization when required.
If you notice unusual noises, lack of stabilization effect, or erratic behavior when IS is enabled, the system might need servicing. Contact Canon support for assistance.
Store the lens in a dry, cool place, ideally in a padded camera bag or case. Use a lens cap and rear cap to protect the elements and contacts. Avoid exposure to extreme temperatures and humidity.