Saturday, July 19, 2008

the one where you make stuff all blurry on purpose.

Another Photography 101 post. Yippee. But unlike the first one where I just rambled incessantly about my thoughts on photography, I'm hoping this one might actually teach you something.

A reminder: Most of these lessons will refer to shooting with a Digital SLR. I will give hints on how you might achieve certain things with a Point and Shoot, but I cannot guarantee your results will be as dramatic.

Also: If you know a lot about the technical side of photography, I welcome your input in my comments. I'm going to try and write these posts as simply as possible for people like me who have had an extremely hard time understanding how it all works.

Finally: This post is long. Sorry. I tried to keep it concise, but this first topic is the most complicated and I had a hard time being brief (big surprise.) If you’re just starting out with DSLR photography, I think it might be helpful, so hopefully you’ll read it!

Today's lesson will be about this crazy thing called Aperture. Don’t be scared. I’ll be gentle.

Here's the thing:

When I got my DSLR (a birthday present hand-me-down from my dad), I spent the first two months shooting photos in completely automatic mode. Everything was automatic. Auto Focus. Auto ISO. Auto Flash. Auto Aperture. Auto Shutter Speed. Auto White Balance. Auto everything else you can think of. Words like Aperture and Shutter Speed scared me.

My dad's advice (and the advice I am going to give you) was to start taking my camera out of each auto mode ONE AT A TIME. As you do this, you will learn how each aspect of the camera works, while letting the camera figure out the rest. This method of learning has worked well for me. Put another way, I learned how Aperture worked first by letting the camera do everything in Auto mode, while I changed only the Aperture settings. I used Aperture-priority mode for a couple of months before I started to understand how it worked.

Aperture has been the most difficult and intimidating photography concept for me to understand, but I’m going to start with it first, because I also think the results of understanding Aperture are the most immediately rewarding. This will also be the longest and most challenging lesson, so take a potty break and an aspirin before you begin. Your head might hurt when we’re finished, but it will be worth it. Once you get Aperture, understanding the other settings in your camera will be even more fulfilling.

This lesson will be written in three parts:

PART ONE – An explanation of Aperture
PART TWO – A hands on homework assignment about Aperture
PART THREE – A whole bunch of photos illustrating Aperture

If all the technical mumbo-jumbo scares you, perhaps skip straight to Part Two without even reading Part One. If you’re like me, you learn by DOING, not be reading about it. You don’t necessarily have to understand the hows or whys behind Aperture to make it work for you. So skip ahead if you like!

PART ONE – An explanation of Aperture

To begin with Aperture, first, an explanation about light:

With photography, light determines almost everything. The basic formula of a photograph is based on the AMOUNT of light that comes into the camera, the DURATION of the light that comes into the camera and the SENSITIVITY of your camera to that light.

In other words, pretty much anything you are going to adjust on your camera is to change the relationship between the AMOUNT and DURATION of the light entering the camera, combined with the SENSITIVITY of the camera to that light.

Aperture refers to the AMOUNT of light that comes in. Shutter Speed refers to the DURATION of the light that comes in. ISO refers to the SENSITIVITY of your camera to the light that comes in.

Aperture = AMOUNT of light.

Shutter Speed = DURATION of light.

ISO = SENSITIVITY of the camera.

We’ll talk about Shutter Speed and ISO in the later posts. Let’s focus on Aperture for now.

My dad explained Aperture to me like this: If you turn on your kitchen faucet, Aperture is HOW WIDE the opening of the tap is. A wide-open tap means a lot of water is able to come through. A wide-open Aperture means a lot of light is able to come through. A small Aperture is like making the opening of the tap smaller, or narrower. Not as much water can get through. But, the water that does get through is more concentrated.

Stop and let that sink in for a minute. This part is important. Go to your kitchen sink and turn on your faucet if you have to. I'll wait.

Wide opening = lots of water = less focused = water all over the place as it comes out.

Narrow opening = less water = more focused = water more concentrated as it comes out.

With a wide-open Aperture, more light comes in, but it will be less concentrated. With a small pin-hole sized Aperture, less light comes in, but it will be more concentrated.


There are numbers on your camera that represent the how wide (or not wide) the Aperture is open. These numbers are CONFUSING and BACKWARDS. It makes no sense to me. Accept it and move on. Find some special way of understand this that is unique to you because if you're like me, the numbers will never make any sense.

And, to make it worse, someone decided to put the letter “f” in front of Aperture settings. It’s called the f-stop. I think the “f” stands for fractional. Yuck. I hate fractions.

If the Aperture number on your camera is small (f/2) it means your Aperture is wide open. If the Aperture number on your camera is big (f/22) it means your Aperture is narrow. I have no idea why a wide-open Aperture is a small number and narrow Aperture is a big number. It's backwards to me. I'm sure there's some mathematical equation that explains it, but I have no idea. I think it has something to do with fractions. Did I mention I hate fractions?

My brain hurts. Yours? Take a minute if you have to and then come back.

Okay. Welcome back.


APERTURE is about how WIDE (or NOT WIDE) the lens is open. It’s about the AMOUNT of light entering the camera.

A SMALL number (f/2) = wide open Aperture = lots of light = light all over the place.

A LARGE number (f/22) = narrow Aperture = not as much light = more concentrated.

Read that again and really try to understand it. This is the hardest thing I’ll ever explain in my photography posts, but it’s important. Give your temples a massage and let it compute.

Next. Why do these numbers actually matter? Well, here’s the super-exciting-awesome reason you’ve read this far:

You know how some photos look totally awesome because the subject is in focus, but everything other than the subject is all fuzzy looking? And because the subject is in focus, but everything else is all fuzzy looking, the subject really pops out of the photograph? Like this:


This has to do with Aperture. Aperture affects something in photography called DEPTH OF FIELD.

In your photos, EVERYTHING from front to back can be in focus, or only ONE PART of your photo from front to back can be in focus. And you can actually control this with your Aperture settings. Cool, eh?? Here’s the same photo with everything from front to back in focus:


Any guesses on what the Aperture setting was for each of the photos? Was the “f” number big or small? Remember: Small number, big opening, lots of light, but not very concentrated. Big number, small opening, less light, but very concentrated.

Did you guess right?

In PHOTO 1, the Aperture was set to f/1.8.

Small number. Big opening. Lots of light, but not very concentrated. I focused on the flower before pressing the shutter release and because the Aperture was wide open, lots of light came in but it wasn’t very concentrated. When the shutter is open really wide, the light scatters all over the place inside your camera and most of your photo, except for your FOCUS POINT, ends up fuzzy.

In PHOTO 2, the Aperture was set to f/11.

Big number. Small opening. Less light, but very concentrated. I focused on the flower before pressing the shutter release, and because the Aperture was very narrow, less light came in, but it was very concentrated. When the shutter is very narrow, the light focuses sharply on everything that the camera sees from front to back.

I have a general rule of thumb for myself regarding Aperture:

If I am shooting a single subject, I use a larger Aperture opening (or, a smaller number like f/1.8 - f/5.6) as in PHOTO 1. It makes the subject stand out from it’s background. This works well for portraits of a single individual and other single objects.

If I am shooting multiple subjects, I use a smaller Aperture opening (or, a bigger number like f/16 - f/22). With multiple subjects, I want to make sure everything is in focus from front to back. This applies to things like group portraits and landscapes.

Now here’s the ADVANCED CLASS:

When you have a large aperture opening (f/1.8), the amount of light that gets in is large, so you don’t need very much natural light to get a good picture. You could take a photo at f/1.8 at dusk and still get a clear photo of your subject.

When you have a small aperture opening (f/22), the amount of light that gets in is small, so you need much more natural light to get a good picture. It’s much more difficult to get a good picture at f/22 at dusk than at noon.

Shutter speed and ISO factors in here too, but I’m sure your brain is ready to explode, so I won’t go there.

PART TWO – A hands on homework assignment about Aperture

And now for your Aperture homework. This is trial and error time. Learning by doing.

Make sure your DSLR is completely in Auto Mode. You may need to pull out your manual for this. I have a Nikon D70s. When I turn it on, the little screen tells me that everything is in Auto Mode. I'm repeating myself, but for this lesson, make sure the following things are set to automatic first: ISO, White Balance, Focus etc.

If your camera is new to you, you may never have changed these things, so everything may already be in auto-mode.

Now change ONE THING: Aperture.

Switch your DSLR camera to Aperture-priority. This means that you will be able to set the Aperture to whatever number you want and everything else will figure itself out automatically. The Aperture is your priority. On my camera, you turn the dial on the top to the letter “A”. Yours might say “Av”. Check your manual to find out what to do with yours for Aperture-priority.

POINT AND SHOOT HINT – Most Point and Shoots have an Aperture-priority mode too. It also usually says “A” or “Av” on the dial. The major difference with a Point and Shoot will be how large or small you can make the f-stop. On my Point and Shoot the Aperture range is f/2.6 – f8, whereas on my DSLR (with a standard 50mm lens) the range is f/1.8-f22. The Point and Shoot will allow Aperture-priority and do a good job, but the results will not be quite as dramatic.

With your camera in Aperture-priority mode, change the Aperture number to the smallest number possible for your camera. The type of lens you have on the camera will determine what this smallest number is. The exact number isn’t important. Just make it small. Somewhere between f/1.8 and f/4.5 will work for our example. Just do whatever is smallest.

On my camera, you can change the Aperture number by turning the dial on the front of the camera under the shutter release. Check your manual to figure this out, or play around with the dials or buttons until you see something changing. (In Aperture-priority mode, the Shutter Speed will also move automatically as you change the Aperture. Try not to let this confuse you. Just ignore it and move on. I’ll explain Shutter Speed in my next post.)

Great. Your camera is set to a very small Aperture number. Now go find a subject that meets the following criteria:

1. Choose a subject where there is a good amount of natural light. Direct sunlight is fine. Shadows not as good. Somewhere in between is best. Don’t do this inside a dark room or outside at night. We’ll learn to shoot it difficult lighting situations some other time. Right now, give yourself the best chance for success.

2. Choose a single object like a flower that stays still. Pets and kids move too much which makes learning more difficult.

3. Stand fairly close to your subject. The results won’t be as dramatic if you are across the street from it. This has something to do with how DEPTH OF FIELD works, but it’s confusing, so trust me, stand relatively close to the subject.

4. But, don’t get too close, because you want enough stuff in the frame around and behind your subject for it to get all fuzzy. Maybe two or three feet away is good.

Now take a picture. Make sure you focus on your subject. If your camera is set to Auto Focus, it should find your subject in the middle of your lens and focus on that.

Did you take the picture? Good. Now review it on the screen. Is your subject in focus? Good. If not, check your FOCUS POINT and make sure it was on the subject. Check your manual to figure this out.

Was all the stuff other than your subject all fuzzy? Good! Isn’t that cool? A small Aperture number (wide opening) will give you a clear subject with a fuzzy background, which really helps the subject to pop in the photograph.



Change your Aperture number to f/22 or the largest number your camera will allow. Don’t go higher than f/22 unless it’s a bright sunny day because there’s not enough light to get a good picture. If it’s an overcast day, perhaps set your Aperture to somewhere around f/16.

Now take a photo of the same subject. Did you take the picture? Good. Now review it on the screen. Is your subject in focus? Good. Was everything else in the photo in focus too? Good!

POINT AND SHOOT NOTE: The limitation of a Point and Shoot is that the Aperture might only go up to f/8. There’s some technical mumbo-jumbo that my dad explained to me about how Point and Shoots are designed to have a larger focus area generally, or something like that. Actually, this is what he told me when I asked him to explain why the Point and Shoots work differently in this regard:

"Point and shoot cameras use different auto focus techniques which will tend to achieve overall "in focus" - the camera tries to achieve good focus over the entire field of view whereas the DSLR camera focuses on the spot. This results in an image that is not in perfect focus anywhere, but good focus everywhere."

I don’t quite understand, but the Point and Shoots don’t work quite the same, so the results won’t be exactly the same. Either way, it’s fun to play with the settings to see what you can achieve.

Personally, I love the Aperture-priority mode because an interesting Depth of Field is what takes photos to the next level for me.

So. How did you do?

Do you have a slightly better understanding of what Aperture is? I hope so. Are you less afraid to take your DSLR out of Auto mode? I hope so!

I would be thrilled to bits if you posted some of your Aperture-priority experiments on your blog. Please leave me a comment if you do so I don't miss it.

Moving on...

PART THREE - A whole bunch of photos illustrating Aperture

For single subjects like a flower, choosing a lower Aperture setting (like f/1.8) will really help your image pop. For Point and Shoots, instead of using your Aperture-priority setting you can also choose a "Portrait" mode to get a blurry background.

Here's a sequence of photos that clearly illustrates how changing the Aperture setting affects the DEPTH OF FIELD. At a lower Aperture setting the Princess in the front is the only figure clearly in focus. And as you dial the Aperture up (increase the number, but make the opening smaller), step by step each of the figures will become more in focus. In a situation like this, it's a matter of deciding how much or how little you want to be in focus and then changing the Aperture setting accordingly. If you are taking a photo of a group of people who are standing in several rows one behind another, it's a wise idea to use a higher Aperture setting (big number, small opening) so that all of the faces are in focus from front to back, as in the last photo here at f/22.

And a few more shots to illustrate the point...

See how Red Dragon really stands out from the background when it's all blurry behind him? That's the prize for understanding how Aperture works. Cool, eh??


Something to notice is that in the above photo at f/1.8, Red Dragon is a little blurry himself. He's not as SHARP as you might like (click to enlarge). If you want your subject to be very sharp, make sure you don't dial the Aperture setting down too low. I find with certain lenses the "sweet spot" for ultimate sharpness is somewhere between f/5.6 and f/8. It also depends on availble light, but check out Red Dragon in these next two shots. I think he looks better at f/5.6 than at f/1.8. The background is still blurry, but Red Dragon is sharp and clear.

And then notice when I take the Aperture all the way to f/22... the image looks darker. It's not as bright because I was in the shade here and didn't have much light on Red Dragon. At f/22, the Aperture opening is too small to let enough light into the camera for the subject to be well lit. On overcast days, you will not have much success at a higher Aperture setting (well, until we learn to adjust the ISO or Shutter Speed to compensate for this). But for now, don't be surprised if your photos are quite dark when shooting in Aperture-priority mode at f/22 on a cloudy day.

A couple more shots to illustrate Aperture differences...

I like low Apertures for a flower like this because I don't really want to see the bark mulch on the ground clearly as you do at f/22. But, I also haven't gone too low because if I had shot this at f/1.8, the entire flower from front to back might not have been totally sharp.

I especially like lower Aperture settings to make more delicate objects stand out from their background, like this:

vs. this:

Or this:

vs. this:

And finally, one more sequence to show you how the different Aperture settings make a shot look. In Aperture-priority mode, I have made no changes in the camera except for the Aperture setting:

And that's about it. Did you learn anything useful?

I hope so!

And now for the extra credit, check out some other posts about Aperture that I think are excellent (and much more succinct than mine):

Angella at Dutch Blitz
Laura at Dolce Pics 1
Laura at Dolce Pics 2
Ree at The Pioneer Woman

That's it. And if you read this far and found this post useful, please let me know because it took me SOOOOOOOOO long to write it.

I want to know if it's worth it to post any more.

Next up (if I do it) would be The One Where You Make Fast Things Stop.

* Special thanks goes out to my mom's garden and Csilla's Little People. *


Corey~living and loving said...

Sorry about that first comment...too many windows open.! the amount of time you spent on that....I am bowing down to you. way to go! You rocked it. I know all too well how much work that took, and you are a wonderful person for doing it.

I hope it helps lots of folks. well done!

laura - dolcepics said...

Hey, that is such a great article! I love all the photos. They are so rich in colour and of course, they illustrate your points perfectly. Great work! I totally understand what you mean about there being so much to write about re: aperture. It's such a major topic when it comes to photography. :) You did an excellent job. Looking forward to more articles.

And thanks so much for the link to Dolce Pics! I'm honoured! :)

Kimberly said...

You are amazing! I didn't even know I could do stuff like that with an DSLR...can't wait to start (slowly) playing around with it!

ciara said...

*sigh* if only i had a dslr. anyways, your post was easy to understand and now i totally get it. of course, i didn't get to read the whole's late, and i want to be able to retain the info so i will definitely come back to it. i just wanted to comment before i forgot what i wanted to say LOL

Jen said...

WOW Carloyn! I just had to say WOW! I'm so HAPPY you did this post! I've read through it, but my brain is all fuzzy and I'm really tired, so I'm gonna come back and read it with my camera in hand and soak it all in. I'm SO EXCITED to finally understand! YIPEE!

Irene said...

Great post! I am sure it will help a lot of people!

As you mentioned, it is harder to see these differences in p&s cameras. Even at very small apertures, their DOF is still huge. I never really realized that until I got some pics from my MIL at looked at the exif data. They were pictures of my daughter in her front yard. Every single thing was pretty much sharp (from close up to trees on the other side of her yard), yet her aperture was only 3.2! I never really realized the difference between my SLR and her camera until that point.

BTW, I ordered my 50 1.8 lens yesterday! I am so excited!!!!

david mcmahon said...

EVERY blogger should read this.


Jan said...

This one is going to bookmarked for sure. There is so much information in here that I felt like I took a college course or something. Fantastic job. Really fantastic. Thanks for sharing and caring.

Jenty said...

Wow!! That must;ve taken forever, but OMW I really enjoyed reading that, I learnt one heck of a lot!

merrymishaps said...

I'm going to have to come back to this when I have more time ... I've had a DSLR since November and have yet to learn how to really use it outside of "Auto" mode!

lissa said...

very helpful post, thanks, I hope you continue to write more of these, still trying to understand aperture even after a year of using the same camera

CrazyCath said...

This is doooo good. Such a brilliant post - and in English!!!

Pleeeasase post more. I do not have a DSLR yet but I am working on it. Maybe one day. And anyway, I have an ordinary SLR and this works for that too. I used to know all this stuff. It is too many years. ;0)
Although I can "feel" my way, it is so good to revise the technical stuff and know WHY I do something. (I tend to just do it - if I turn the lens this way or that I get this or that effect - you remind or teach me why).

Thank you. So glad David has you as POTD - well deserved imho for all that work!

Oh and the aperture numbers? You're right - it's fractions.
Just like ¼ is smaller than ½ but look at the numbers involved at the bottom of the fraction - 4 is bigger than 2. The aperture numbers work the same way. ;0)

lisaschaos said...

Oh yeah, that was one long post but very full of good information. :)

When you mentioned one subject using smaller numbers it made me think 1 subject = 1 digit
single subject - single digit
more subjects - double digits

I know, I'm weird but I found that helpful. :)

Pat - An Arkansas Stamper said...

This is a wonderful article! Thank you for the time and effort that went into it. While I have a general understanding of aperture, this is the best explanation (with examples) I have ever read, far and above better than a camera manual.

I currently have only a 'point and shoot' camera, but am longing for a DSLR.

Thanks, again!