Sigma 17-70mm lens came with hood. How and why do I use it?

The Sigma 17-70mm lens came with a lens hood. I only understand a little about hoods and although it looks pretty cool, if I don't have to have it on I would prefer not to....of course if there is good reason to use it then I will.

So what would be an example of when and why I would want to use it?

The hood can be a lill annoying on the 17-70, especially because it does not let you place the lens cap back on the lens, when it's on the lens. (Not by hand anyways)
It should prevent some flare and can protect the front element from accidents, so use it if you can. It's relatively easy to install and uninstall it, compared to Canon hoods...

Janika wrote in post #2143902
The hood can be a lill annoying on the 17-70, especially because it does not let you place the lens cap back on the lens, when it's on the lens. (Not by hand anyways)
It should prevent some flare and can protect the front element from accidents, so use it if you can. It's relatively easy to install and uninstall it, compared to Canon hoods...

The hood is extremely easy to put on and take off. When you say flare do you mean flare from the sun or a bright sky? To avoid lens flare?

Makes the lens look cool. Why else would you use it?

TMR Design wrote in post #2144161
When you say flare do you mean flare from the sun or a bright sky? To avoid lens flare?

Stray light, whether artificial or natural, can adversely affect image quality, often producing flare and other unattractive specular artifacts. The sun is one major player in this. Using a lens hood, especially the one made by the lens maker for a specific/given lens, really helps in either blocking out or mitigating lens flare. You'll find that your images have better contrast, AF accuracy is better, and simply overall the images will be more pleasing. Lens hoods also serve as physical protection for your front element. Use your hood as much as you can.

LightRules wrote in post #2144180
Stray light, whether artificial or natural, can adversely affect image quality, often producing flare and other unattractive specular artifacts. The sun is one major player in this. Using a lens hood, especially the one made by the lens maker for a specific/given lens, really helps in either blocking out or mitigating lens flare. You'll find that your images have better contrast, AF accuracy is better, and simply overall the images will be more pleasing. Lens hoods also serve as physical protection for your front element. Use your hood as much as you can.

Cool. Thank you. I will do just that.

I just put it on top of my head so it looks like a little crown. The hood from a 70-200 L is big enough to look like a real crown though.

Tee Why wrote in post #2144336
I just put it on top of my head so it looks like a little crown. The hood from a 70-200 L is big enough to look like a real crown though.

I was going to say something similar.....or put it on my coffee mug and say "Hey, this is how I put the hood on my glass"

TMR Design wrote in post #2144161
The hood is extremely easy to put on and take off. When you say flare do you mean flare from the sun or a bright sky? To avoid lens flare?

Here´s a shot with the 17-70 without the hood. Huge flare

I'm going to a car show tomorrow. It's indoors and I would imagine there is a lot of light. Is this an instance of wanting/needing the hood? Will flare happen indoors with that kind of Coliseum lighting?

I tend to always fit the hood reversed, and turn it round when shooting in potential flare conditions. Having the hood on has saved a lens more than once!

If you can't fit the lens cap try getting a Tokina one, they have extra grips in the middle of the cap.

Those inner pinching front caps are readily available from even 3rd party folks, something like this http://cgi.ebay.com …ZWDVWQQrdZ1QQcm​dZViewItem

TMR Design wrote in post #2145378
I'm going to a car show tomorrow. It's indoors and I would imagine there is a lot of light. Is this an instance of wanting/needing the hood? Will flare happen indoors with that kind of Coliseum lighting?

if i recall correctly, flare happens only in extreme lightning conditions. usually, it happens when out in the sun. i doubt you'll get flare indoors, but im sure the hood will come in handy considering the lightning will be pointed in all directions. minimizing stray light will get you some great shots.

Use the hood. All the time. Someday it will save your lens from an unexpected bump. Turn it around and attach it backwards for storage.

unix04 wrote in post #2146078
if i recall correctly, flare happens only in extreme lightning conditions. usually, it happens when out in the sun. i doubt you'll get flare indoors, but im sure the hood will come in handy considering the lightning will be pointed in all directions. minimizing stray light will get you some great shots.

You can get really ugly flare from tungsten lights as well.