Rocky Mountain Joe, What the Heck is an F/Stop and Why Do We Care? ...

$What the Heck is an F/Stop and Why Do We Care? Along my photographic journey, I decided one day that I would learn what “f/stop” was all about, so I googled and read and googled and read. It all seemed very intimidating at first, but it’s really not, and maybe this nugget will speed you along on your understanding of it. Basically, the f/stop setting on your camera allows you to control the size of the lens opening and hence how much the light comes in. The lower the number, the more light comes in. You can set the Aperture explicitly in ‘aperture priority’ mode (Av or A) on your camera’s dial, and then the camera automatically sets the corresponding Shutter Speed so you get the right exposure. There’s a little system of numbers to describe how open or closed the lens is, and for some lenses the sequence is: f/1.4, f/2, f/2.8, f/4, f/5.6. f/8, f/11, f/16, f/22. Some people are confused that the lens lets in more light when the f/stop number gets smaller. Just think if it as the bottom number in a fraction, and everyone knows 1/2 is bigger than 1/4 !! Now, here’s a key point: as you move between the f/stops I’ve listed here, the amount of light entering the camera doubles or halves (depending on which way you’re going.) And, as you change your f/stop setting in Aperture mode, you will notice that the camera automatically doubling and halving the Shutter Speed in a corresponding fashion. (This keeps the exposure the same for a given scene that you’re shooting.) So why do we care? Very briefly, if you’re indoors and want to shoot without a flash, get that aperture open as wide as possible (small number) to let lots of light in. Also, to get that cool fuzzy background in a portrait shot, also use a wide aperture. But to get a crisp landscape shot of the mountains, put your camera on a tripod or brace it against a tree and put the aperture up to f/11! See my chart attached here — I’ve drawn the size of the aperture openings to scale relative to each other. (Not all lenses open as wide as f/1.4. There are very affordable 50mm lenses that do, and I highly recommend them!) A Rocky Mountain Joe® NuggetBoulder, Colorado 2009-11-26Attribution-Noncommercial-No Derivative Works 3.0$

What the Heck is an F/Stop and Why Do We Care?

Along my photographic journey, I decided one day that I would learn what “f/stop” was all about, so I googled and read and googled and read. It all seemed very intimidating at first, but it’s really not, and maybe this nugget will speed you along on your understanding of it.

Basically, the f/stop setting on your camera allows you to control the size of the lens opening and hence how much the light comes in. The lower the number, the more light comes in.

You can set the Aperture explicitly in ‘aperture priority’ mode (Av or A) on your camera’s dial, and then the camera automatically sets the corresponding Shutter Speed so you get the right exposure.

There’s a little system of numbers to describe how open or closed the lens is, and for some lenses the sequence is: f/1.4, f/2, f/2.8, f/4, f/5.6. f/8, f/11, f/16, f/22. Some people are confused that the lens lets in more light when the f/stop number gets smaller. Just think if it as the bottom number in a fraction, and everyone knows 1/2 is bigger than 1/4 !!

Now, here’s a key point: as you move between the f/stops I’ve listed here, the amount of light entering the camera doubles or halves (depending on which way you’re going.) And, as you change your f/stop setting in Aperture mode, you will notice that the camera automatically doubling and halving the Shutter Speed in a corresponding fashion. (This keeps the exposure the same for a given scene that you’re shooting.)

So why do we care? Very briefly, if you’re indoors and want to shoot without a flash, get that aperture open as wide as possible (small number) to let lots of light in. Also, to get that cool fuzzy background in a portrait shot, also use a wide aperture. But to get a crisp landscape shot of the mountains, put your camera on a tripod or brace it against a tree and put the aperture up to f/11!

See my chart attached here — I’ve drawn the size of the aperture openings to scale relative to each other. (Not all lenses open as wide as f/1.4. There are very affordable 50mm lenses that do, and I highly recommend them!)

A Rocky Mountain Joe® Nugget
Boulder, Colorado 2009-11-26
Attribution-Noncommercial-No Derivative Works 3.0