This article explains what a lens hood is, why they’re used, and whether or not you should own one yourself.
What Is A Lens Hood?
A lens hood is essentially a cover that goes over the end of your camera where the lens is located. It can be square, funnel, or cylindrically shaped, and is used to prevent flare and other unwanted stray light from reaching your field of view. Flare is light that shouldn’t be showing up in the photograph. It usually occurs when you’re shooting into a light source. It could show up as a plain area of very bright light or it could take on a circular shape that matches the design of your aperture.
Do I Need a Lens Hood?
While you are not required to use a lens hood, there are some very good reasons why you should. First and foremost, a lens hood also protects the lens of your camera. It can prevent minor damage such as a fingerprint on the lens, or major damage such as breaking the glass of the lens. Lens hoods stick out from the lens, so unwanted scratches and dirt on the lens is greatly reduced because the lens becomes harder to reach.
To hear the other side of the story, no, you don’t need a lens hood. A lens hood is just one more photography item to carry around when you go out shooting. Your hand makes just as good of a lens hood as anything, and because most lenses nowadays are multi-coated the flare will only occur when then sun is in the frame. No lens hood is going to help you with that. Lens hoods only help with flare if the sun (or other light source) is outside of the frame, but shooting onto the lens’s front element.
So What's The Verdict?
My personal opinion is that unless you have butter-fingers or shoot in direct sunlight a lot, you don’t really need to get a lens hood. Your hand will work in most cases (especially if you use a monopod or a tripod) and with the lenses currently on the market flaring and un-wanted contrast are much less common.