Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
It makes for a very precise check of the auto-focus system.
With a zoom lens if the auto-focus is out it may be different at either end of the zoom range. If this is the case it may be better to get it calibrated by Canon. I've found that for a lens less than a year old Elstree will do the calibration for free.