Canon® EOS Digital Photography Photo Workshop

7.6. USING LENS HOODS

Many lenses ship with a hood, which is advisable to use in a number of photographic situations. A lens hood provides protection for the lens, such as from bumping into things or if the lens is dropped, and it can prevent things, such as raindrops, from getting onto your lens and affecting an image as well. If your lens did not come with a hood, Canon makes several from which you can choose.

Generally, hoods mount to a lens bayonet style (meaning they don't require screw threads, they attach by turning and locking them into place, similarly to how a lens attaches to a camera). Canon hoods are notorious for varying as to how tightly they secure to the lens, so you may want to adjust yours by using a dab of museum wax (available in most art stores, used to help secure things like vases or small objects to a counter or ledge) to tighten and/or smooth the mounting action. If your lens hood mounts loosely, in particular, it's best not to handle the lens by the hood. Also, be careful when mounting the lens hood not to thread it incorrectly when you twist it on — you'll be able to tell if you've done so by looking at the side of the lens; the hood will be obviously misaligned.

Perhaps the most important purpose of a lens hood from a purely photographic standpoint is that it helps to prevent lens flare by preventing too much light from coming in from the wrong angle. Lens flare is quite difficult to edit out of a digital image, so preventing it is key to ensuring ...