Why is using the lens hood so important?

Lens hoods, and why to use them all the time?

The past few months I’ve seen a lot of people that shoot without the lens hood, and of course, I ask them about it and tell them what I know (nowadays). It surprises me how many photographers didn’t know about this, even the so called “professional photographers”.
It was clear to me to write something about it.

A few years back, a good friend of mine asked me, why I didn’t use my lens hood while doing a photo walk. I just took it off because there was a shade and I wanted as much light as I possibly could get.
He told me to use the lens hood all the time, outside as well as indoors, to avoid an argument I put the hood back on.
When I later that day reviewed the pictures I took, I remembered what he told me with his wise-ass smirk.
However, I decided to look into it and gosh what was I wrong.

So here is what I find out,

Basically, there are two types of lens hoods, the petal hood often referred as a flower or tulip hood and the round shaped hood.
The “round” hood is mainly for the telephoto lenses, the petal shape for wide lenses to prevent interrupting your picture.
The thinner the tulip shape, the wider the view of the lens.

But why are they so important? First of all, keep in mind why the manufacturers produce them the way they are. Every lens has its own specific and calculated hood, optimized for their own focal length. It all comes down to capturing light. Lenses, especially professional lenses, have a lot of glass, or elements, in them. The purpose of those elements is to direct light in the best possible way onto your sensor.

So what happens when all that light hits the glass? The light will reflect on all those elements in the lens that result in lens flares or a certain glare/wash over your picture. The lens hood will prevent stray light coming in by only letting the light trough that’s in the lens’s field of view.

But it gets better: notice the colors are more saturated if you shoot with a lens hood. The pictures are crisper, the blacks will pop out your picture.
The lens hood will increase the dynamic range, which results in a better contrast.
All this above will also apply when you are taking photos inside. Even indoors or at night you have to deal with all kind of light sources that cause stray light.

Furthermore, it will protect the front of your lens, preventing you to bump into something you don’t expect.

So if you want pictures with better contrast and clarity, use the hood.
Of course, there are times you don’t need the lens hood. For example, if you want flares in some kind of pictures for an artistic
purpose, or when you are using the build in flash. Because the hood can create a shade on your pictures.

If you have forgotten your lens hood or lost it, use your hand like you do when you’re looking into the sun or you can find some
shade from a tree or building. You can even throw your back to the sun or the light to create a shadow.