I shoved my phone in my husbands face to show him apicture Id taken of the New York skyline.

Its good, right?

I asked, way too proud of myself because, frankly, it was not good.

Well, he said.

Imagine how good it would look if you knew what you were doing.

I rolled my eyes but took him up on his offer to teach me about exposure.

I always had a vague understanding of my cameras exposure options.

I knew they hadsomethingto do with the lighting situation.

Aperture

Aperture is measured in f-stops and its basically the amount of light your lens lets in.

So whats with the f?

The f/stop is a ratio.

On a 50mm lens, f/2 is saying that the diameter of the aperture is 25mm.

The ratio is: 50/25 = 2.

When you shoot something super bright, like the moon, you want a narrow aperture.

The faster the shutter opens and closes, the less light can get in.

If its open for a long time, it will let in quite a bit of light.

If you let in too much light, your photos can look blurry.

This can happen if you move the camera, too.

Shutter speeds are measured in mere fractions of a second.

An action shot might call for a shutter speed of 1/1200 seconds.

But this varies depending on the image.

ISO Sensitivity

ISO is the third part of the triangle.

It stands forInternational Standards Organization, as its a standardized scale for measuring sensitivity to light.

In film photography, ISO tells you how sensitive film is to incoming light.

In digital photography, your camera has its own sensor with its own ISO parameters.

you’re able to take a brighter picture without flash byadjusting the ISO upward.

The problem is, a too-high ISO can take all the detail out of your photo.

Unlike with shutter speed and aperture, there really isnt a good reason to have higher-than-needed ISO.

I suppose that some photographers do enjoy this look when it evokes the grain texture that sensitive film has.

But as colored pixels, its not usually flattering.

Here are a few examples and the exposure options I used.

The Moon

Moon photographers follow something called the Looney 11 Rule.

Youll need a telephoto lens with a focal length of at least 300mm.

They recommend using a wide angle lens to capture everything.

Heresthe lens I usefor pretty much everything.

In the above photo (of fellow Lifehacker writer Stephanie Lee!)

Looking back, maybe I shouldve narrowed the aperture more and just hiked up the ISO.

Photography Mad recommends starting at 1/500.

I adjusted my shutter speed to 1/2500 to catch the action.

Water in Motion

Shutter speed is the name of the game with waterfall photography, too.

Again, you need a quick shutter speed to catch the water in motion.

The setting depends on how fast the water is moving, so it can be hard to gauge.

It also depends on what kind of photo you want.

Experiment and see what works for you, but these tweaks should get you started.

The Night Sky and Stars

One of my favorite subjects to photograph is the night sky.

I suck at it, but thats what makes it fun.

Its just a lot of trial and error.

Obviously, I am not a pro.

Its possible to take a much better photos.

But thats the point: learning how exposure tweaks work together is crucial to figuring outhowto take better photos.