A couple years ago on one of my photography workshops, an attendee asked "What the 'F' does that mean?!"
It was a great and valid question - he was asking about aperture, f/stops, and what it all meant and more importantly, what it does and how he could improve his photography.
In a nutshell, the definition of aperture is 'an opening, a hole, a gap, slot, crevice, crack and the list goes on and on about simply, an opening.
Within each of our lenses, there are aperture blades that increase or decrease in size depending on the aperture we use.
For example, at f/2.8, the hole or opening inside our lens is wide open.
Visually, imagine a 5" pipe.....
At f/5.6, the hole is more closed.
Visually, imagine a 3" pipe.... the diameter of the hole is getting smaller.
The numbers keep going and going from f/8 to f/11, f/16, f/22, f/32/ f/64, f/90 and so forth.
The higher the f/stop number, the smaller the diameter of the hole light passes through...
In this example, f/2.8 would be like a 5" pipe and f/32 might be like the diameter of a straw.
Also, the higher the number f/16 or greater (like f/22, f/32....), the more depth of field you get. In basic terms, more objects in your photograph will be sharper throughout your image.
Here are some examples of desert plant life starting at f/2.8 and moving towards f/22... You will notice more and more of the image gets clearer as I work towards f/22.
IF you have any questions, please comment below :)
Using Different Apertures
You can see that at f/2.8 (or the lower the number) not much is sharp or in detail except a small selection of the photograph.
As you increase your f/stop to f/5.6 or f/8 or higher, more of your objects become sharper and carry detail.
At f/2.8 (left image), the tree to the right and the horizon in the distance are fuzzy (soft).
At f/22 (right image), the tree to the right and the horizon are a lot more recognizable.
Now there are a couple ways to adjust your aperture settings.
A lot of digital cameras will have a knob, dial or a menu option to switch from PASM.
P - Program mode: A slight notch above auto mode... You get to adjust your ISO and exposure compensation and that's about it! (Not a good setting to use...)
A - Aperture mode: You set your ISO, choose your aperture and the camera will find the right shutter speed with the given light condition. This setting is mostly used for landscapes or product work.
S - Shutter mode: You set your ISO, choose your shutter speed and the camera will find the right aperture with the given light condition. Mostly used for fast moving subjects like sports, wildlife, weddings or long exposures.
M - Manual mode: Meaning you are in full control of adjusting your ISO, aperture and shutter. All the camera has to do is focus and take the photograph.
If you have a Canon camera, you'll see an option labeled "AV"
If you use a Nikon, you'll see an option "A" in or under "mode".
The best way I recommend getting used to aperture and seeing what it does, is taking your digital camera and photograph a yard stick or a 5' measuring tape. Focus around 3' to 4' in front of you and then start adjusting the aperture and see what happens.
With this exercise, you'll see more of the measuring tape or yard stick come to life.
Again, as you increase your aperture number, just like in my photo example above, more and more of the desert got in focus. At f/2.8, very little was sharp - only a few needles on the cactus. At f/22, most of the image was recognizable.
Enjoy aperture and let me know if this helps!
Here are other examples of how I used aperture...
At f/2.8, I wanted to focus the viewers attention on the small pinecone.
At f/22, everything was sharp from the small desert brush to the Totem Pole in Monument Valley.
I use higher f/stop numbers with the majority of my work. This allows more items to be in focus and sharp.
One last thing about aperture. The more you stop down, meaning using higher f/stop numbers, the longer your shutter speed will be.
You have two 5 gallon buckets of water.
When you pour the 5 gallons down a 5" pipe, it'll flow faster than pouring the same 5 gallons of water down a garden hose right?
That's exactly whats going on with aperture when you use higher numbers, the camera will automatically adjust the shutter speed for you. Try my experiment of the yard stick. As you move through different apertures, you'll hear the shutter open and close faster at f/2.8 and take a tad longer at f/22.
Enjoy using aperture!
If you want to join me on a photography exclusion in the Southwest, view the destinations here.
PS: If you want to keep in touch, simply submit your first name and email below. More tips to come!