Introduction to Aperture in Digital Photography


Over the last couple of weeks I’ve been writing a series of posts on elements that digital photographers need to learn about in order to get out of Auto mode and learn how to manually set the exposure of their shots. I’ve largely focussed upon three elements of the ‘exposure triangle‘ – ISO, Shutter Speed and Aperture. I’ve previously written about the first two and today would like to turn our attention to Aperture.

Before I start with the explanations let me say this. If you can master aperture you put into your grasp real creative control over your camera. In my opinion – aperture is where a lot of the magic happens in photography and as we’ll see below, changes in it can mean the difference between one dimensional and multi dimensional shots.

What is Aperture?

Put most simply – Aperture is ‘the opening in the lens.’

When you hit the shutter release button of your camera a hole opens up that allows your cameras image sensor to catch a glimpse of the scene you’re wanting to capture. The aperture that you set impacts the size of that hole. The larger the hole the more light that gets in – the smaller the hole the less light.

Aperture is measured in ‘f-stops’.

Aperture Diagram - f-dtops

You’ll often see them referred to here at Digital Photography School as f/number – for example f/2.8, f/4, f/5.6,f/8,f/22 etc. Moving from one f-stop to the next doubles or halves the size of the amount of opening in your lens (and the amount of light getting through). Keep in mind that a change in shutter speed from one stop to the next doubles or halves the amount of light that gets in also – this means if you increase one and decrease the other you let the same amount of light in – very handy to keep in mind).

One thing that causes a lot of new photographers confusion is that large apertures (where lots of light gets through) are given f/stop smaller numbers and smaller apertures (where less light gets through) have larger f-stop numbers. So f/2.8 is in fact a much larger aperture than f/22. It seems the wrong way around when you first hear it but you’ll get the hang of it.

Depth of Field and Aperture

There are a number of results of changing the aperture of your shots that you’ll want to keep in mind as you consider your setting but the most noticeable one will be the depth of field that your shot will have.

Depth of Field (DOF) is that amount of your shot that will be in focus. Large depth of field means that most of your image will be in focus whether it’s close to your camera or far away. For example the landscape shot above has an aperture of f/16 and the result is that both the mountain in the background and the boats in the foreground remain in focus.

Small (or shallow) depth of field means that only part of the image will be in focus and the rest will be fuzzy (like in the portrait at the top of this post. You’ll see in it that the subjects eyes are in focus but the background is blurred. Even her hair which is only a little behind her eyes is blurred. This is a very shallow depth of field and was taken with an aperture of f1.8).

Similarly this creative birth announcement image was shot at f1.8 and again you see the shallow depth of field with the ultrasound in focus but everything else blurred.

Here’s one more example with an even wider aperture of f1.2 that leaves the guitar in focus but everything else blurred.

Aperture has a big impact upon depth of field. Large aperture (remember it’s a smaller number) will decrease depth of field while small aperture (larger numbers) will give you larger depth of field.

It can be a little confusing at first but the way I remember it is that small numbers mean small DOF and large numbers mean large DOF.

Let me illustrate this with two pictures I took earlier this week in my garden of two flowers.

Side by side aperture depth of field example.

The first picture on the left was taken with an aperture of f/22 and the second one was taken with an aperture of f/2.8. The difference is quite obvious. The f/22 picture has both the flower and the bud in focus and you’re able to make out the shape of the fence and leaves in the background.

The f/2.8 shot on the right has the left flower in focus (or parts of it) but the depth of field is very shallow and the background is thrown out of focus and the bud to the right of the flower is also less in focus due to it being slightly further away from the camera when the shot was taken.

The best way to get your head around aperture is to get your camera out and do some experimenting. Go outside and find a spot where you’ve got items close to you as well as far away and take a series of shots with different aperture settings from the smallest setting to the largest. You’ll quickly see the impact that it can have and the usefulness of being able to control aperture.

Some styles of photography require large depths of field (and small Apertures)

For example in most landscape photography you’ll see small aperture settings (large numbers) selected by photographers. This ensures that from the foreground to the horizon is relatively in focus.

On the other hand in portrait photography it can be very handy to have your subject perfectly in focus but to have a nice blurry background in order to ensure that your subject is the main focal point and that other elements in the shot are not distracting. In this case you’d choose a large aperture (small number) to ensure a shallow depth of field.

Macro photographers tend to be big users of large apertures to ensure that the element of their subject that they are focusing in on totally captures the attention of the viewer of their images while the rest of the image is completely thrown out of focus.

I hope that you found this introduction to Aperture in Digital Photography helpful. Be sure to also check out our introduction to Shutter Speed and introduction to ISO.

Enjoy this post? Subscribe to dPS to get a weekly newsletter with all our latest tutorials – it’s all completely free.

Read more from our category

Darren Rowse is the editor and founder of Digital Photography School and SnapnDeals. He lives in Melbourne Australia and is also the editor of the ProBlogger Blog Tips. Follow him on Instagram, on Twitter at @digitalPS or on Google+.

  • BRE

    ur old XD

  • Mihir malik

    Depth Of field depends on 3 parameters :
    1. Zoom .
    More zoom , more the blur.
    2.distance from the object .
    More the distance , more the blur
    3. Aperture.
    Lower the F no. Greater the blur

  • Anuj Grover

    Thanks Darren,
    Such a well explained article. Clear and precise. I am very new to photography, don’t own a DSLR but I do try and experiment as much with my point-n-shoot. This photo is taken at a fairly Large aperture of 5.8 & gave lesser depth of field (and a rather uplifting effect to these lovely flowers).
    The large / small numbers/ values / DOF’s now start to make more sense.

    The article really helped me understand my own photograph. Thanks a bunch 🙂

  • I have a tutorial on Depth of field on my website if anyone needs it… 🙂

  • Hanraa Haa

    thank you, the large d.o.f = big number, small d.o.f = small number, has really helped me understand aperture in a way i will be able to remember easily.

  • Wingstem Tee

    For E-m1 aperture mode can I set the shutter speed at that mode?

  • k


  • k


  • HI

    im a pro phoptographer

  • Dilip kumar

    I’m Dilip Kumar, from Bangalore.

    Please any one do let me know a answer for one question please

    Question is the aperture number given f/2.8, f/4, f/5.6,f/8,f/22

    why is it not 1234567 random
    how is it measured and fixed with what idea

    my answer for this question was that I said “the iris of aperture when selected– it opens all round from edges from all the sides ”

    but a camera man said, no its wrong– yourself find the answer and do let me know
    please anybody reply me with answer
    My E mail ID “”

    Thannk you


    Thank you DPS!

  • twg

    Thank you for your summary 🙂
    Greatly appreciate it! I am a enjoyer of photography but I haven’t questioned what aperture was for 10 years. Now I have ‘somewhat’ of an idea haha

  • Paula

    Ok, I am kind of confused. If I want to shoot at night and want to capture the stars/ moon would I need a large or small aperture? My mind is saying small to capture more detail but large because it is dark to let as much light as possible in. I am new to photography and only starting to understand things but aperture seems to be a bit harder to understand

  • Sarine Lawson

    Hi Darren,
    I love photography and over the years have been taking tons of photos of my boys, after having two cameras, a Canon and a Nikon I finally invested on aNikon Coolpix P530(hope it’s the right choice). Both my boys are hockey players and I would live to be able to take some good quality photos which on the rink playing. I set my ISO at the highest which is 6400 for my camera and the aperture to the smallest number which is f3.0 for my camera. Is this right the right setting, what else would you recommend for good quality result?
    Many thanks!

  • your mom


  • Luke

    I just researched this, myself, because I wanted to know what two f-stops are and then why my camera showed some extra (half-stop) numbers. As I understand it, light exposure, as perceived by the human eye/brain, relates logarithmically. According to this page ( on wikipedia, the full f-stops are calculated in sequence by “2^(0*0.5), 2^(1*0.5), 2^(2*0.5), 2^(3*0.5), 2^(4*0.5) etc.” and half f-stops by “2^(0/2*0.5), 2^(1/2*0.5), 2^(2/2*0.5), 2^(3/2*0.5), 2^(4/2*0.5) etc.” And I converted that with some success (although perhaps not with the correct y-intercept) to f(x)=2^(.25*(x-1)) to calculate the half f-stops. I hope that helps, but if you’re confused definitely refer to that wikipedia page.

  • Jeunii

    Amazing pic !

  • Anuj Grover

    Thanks 🙂

  • UG

    Although not always possible/practical, inceasing the distance between the subject and background will also help you blur the background.

  • UG

    I’m not a star shooter, but I had good success shooting the blood moon this year with aperture of f2.8 and a shutter speed of 4 seconds.

  • NikonP600

    Love my new Nikon P600 but really disappointed with my basketball shots. Should I try adjusting the aperture to an f22 instead of using the sports setting which isn’t giving me the clear shots I am hoping for?

  • Simran

    Thanks for sharing this information, but i guess at some points Aperture makes me confuse, f/22 is Smaller than f/4.8, and your saying small number means small DOF and large number large DOF. In the top ocean pic Aperture should be large, So it should use f/4.5 not f/22, Is that true?

  • ansaree97

    I was having some difficulty understanding aperture.. But this cleared it out for me.. What I don’t understand is that in Astrophotography, the aperture that photographers recommend is high.. Like f/4.0 to f/1.8..Or even higher but, as u said that higher aperture means lesser DOF and you can focus on foreground to make background blurry..What I don’t get is how can they use higher aperture to capture the sky (stars, nebulae etc) which are distant..while it’s usage is for close shot and portraits.

  • ali

    for school i have to do long depth and short depth what iso,shutter speed and aperture should i use i have no idea

  • Sadat Baloch

    i am very new in photography i like to learn more and share my pictures to you sir . i read your articles these are very helpful i tried some of your tips it works for me.

  • Sadat Baloch

    what you say about this picture? i am was not aware of the term f/ and DOF can you tell me more about these?

  • Vipul

    By which camera you have taken this?

  • Anuj Grover

    A Nikon Coolpix L820

  • Vipul

    gr8 photo….!

  • cornstar

    thankyou for your help on my assignment your were great 10/10

  • Katy

    I found this really helpful – thanks!

  • madison


  • Arup Das

    Someone telling me about the aperture – “at minimum aperture is f22. And at 55mm minimum aperture is f36. At 24mm as per my exif, minimum is f25.” what is the true fact

  • PIcture bunny

    Thanks, this was really useful. But out of curiosity, is math related to all these (aperture, f-number, shutter, shutter speed and DOF)?

  • Celene

    I take pictures for an animal rescue group. I use a 50 mm lens with f/1.8 and use spot focus. I do not understand why the eyes of my subject is in focus, but the nose is blurry. Can you help me with this problem?

  • IrinaM

    I hope references on other sites are allowed. When taking photography class I was recommended an absolutely fantastic site designed as DSLR Camera simulator. You can play with ISO, Aperture and Shutter speed and “take pictures” to see your results. Totally amazing.

  • David Voros

    What I struggle with is where do you set your focus point? In your example above with the Japanese boats, did you focus on the sand, the boats or somewhere just beyond the boats to achieve great DOF?

  • bv

    simplest thing to do is associate the F number with the size of the COVER, not the opening.

  • Sheree Brown

    Easy way to remember, “The larger the number the smaller the hole, the less the light”

  • Those photos are really awesome, the photographer have a admirable skill. Jabong promo codes

  • Midix

    Hey, remember that aperture numbers are reversed, as it was mentioned in the article. High aperture number means that the aperture itself will be small, which will make DOF to be large enough to have sharp image of stars. With shallow DOF you cannot shoot stars because it is not possible to focus on specific star with an ordinary camera.

  • Saswati

    WOW, finally I got this funda cleared…Thanks for explaining so beautifully…I have just started learning photography and always had question marks/but/if whenever it came to DOF, I think I am clear now…will check it out practically today 🙂 Thanks again 🙂

  • Colin Christopher

    this topic answered a lot of my questions regading aperture… thanks much

  • Good tutorial for beginner. Thanks for sharing.

  • Good tutorial for beginner. Thanks for sharing.

  • Sam

    I’m trying to set the largest aperture on my Canon EOS Rebel T5 but I seem to only be able to find the largest aperture of 5.6……. I love pictures that have everything but the subject blurred; I’ve been trying to take pictures of that kind. Could it be that the largest aperture on my camera is 5.6 and so I just have to deal with it? (As you probably have realized already, I am an amateur! I have no experience with photography except often borrowing friends’ cameras to take pictures. Please help! I have a HUGE passion for photography.)

  • Deep

    Hi, friends!
    I have nikon d80 dslr, but I don’t know that how to set its function to capture bright and beautiful pictures. When I capture pictures, it got darker images.

  • Deep

    I have camera zoom of 18-105

  • Marigold

    You are an EXCELLENT TEACHER!!! I went through some courses before and came out all confused!! You stated everything so clearly, so a BIG THANK YOU!!!!!

  • Arunava

    Would like to point out a small error in the post.. The concluding paragraph reads:

    I hope that you found this introduction to Aperture in Digital Photography helpful. Be sure to also check out our introduction to Shutter Speed and introduction to Shutter Speed.

    Introduction to Shutter Speed is repeated, with the second link pointing to Intro to ISO settings page. Perhaps the editor would want to correct it.

    Plus, my thanks for the wonderful site, article and explanation.

Some Older Comments

  • Tuesday Tip: Aperture for Beginners May 8, 2012 02:03 pm

    [...] to Digital Photography School, aperture is ‘the size of the opening in the lens when a picture is taken.’  The larger the [...]

  • Aperture | Rosmile's Photography May 4, 2012 11:20 pm

    [...] size of the opening in the lens when a picture is taken. According to the article I’ve read here, when you hit the shutter release button of your camera a hole opens up that allows your cameras [...]

  • Camera Aperture | My Camera Corner April 19, 2012 06:29 pm

    [...] To Properly Use Your CameraMy Dream CameraCamera ‘Feature Clutter’: How to Avoid the ConfusionIntroduction to Aperture in Digital Photography.broken_link, a.broken_link { text-decoration: line-through; [...]

  • Joey Bouchard Photography ‘Wide Open’: Weekly Photography Challenge April 15, 2012 04:26 am

    [...] images in the collection were all shot with large Apertures. Remember a large aperture (a big wide open hole in your lens) translates to a low number. So the [...]

  • ‘Wide Open’: Weekly Photography Challenge | Basic Digital photography ( Let s Photo) April 14, 2012 02:03 pm

    [...] images in the collection were all shot with large Apertures. Remember a large aperture (a big wide open hole in your lens) translates to a low number. So the [...]

  • ‘Wide Open’: Weekly Photography Challenge | Benjamin Hall April 14, 2012 08:21 am

    [...] images in the collection were all shot with large Apertures. Remember a large aperture (a big wide open hole in your lens) translates to a low number. So the [...]

  • Photo Session 4: Capturing Motion | Emil's Cerebrations March 27, 2012 04:11 pm

    [...] week, we’re covering aperture/depth-of-field effects in my course. The Cherry Blossom Festival presented me with good opportunities to [...]

  • me + apeture mode = LOVE « sarahvictoriaphotography February 28, 2012 04:24 am

    [...] For more technical info go here. [...]

  • Aperture « Shutter bug February 21, 2012 01:32 am

    [...] photography and life, and share the fruits of our assignments.  Our latest assignment – aperture.  Using a macro lens, the same photo 3 times, all using a different aperture.  Being unable to [...]

  • Understanding Photography: What is Aperture? « February 17, 2012 04:55 am

    [...] What is aperture? Think of aperture as a small hole in the lens of your camera (because that’s exactly what it [...]

  • LENSES 101 | Kinetic Production February 12, 2012 03:19 pm

    [...] I won’t get into all the details, but here are a few articles that can help you as you learn about lenses. [...]

  • Movement and Miniatures Assignment | sgidigitalphotography2 February 11, 2012 01:34 am

    [...] [...]

  • A Beginners Guide to Photography February 4, 2012 08:17 am

    [...] Original Article(Click Here) Share this:TwitterFacebookMoreTumblrRedditLinkedInStumbleUponDiggLike this:LikeBe the first to like this post. [...]

  • The Natural Look | Photography Critique February 2, 2012 07:37 pm

    [...] The perfectly shallow depth-of-field, shot at f2.8, gives a blurred background.  Given the soft colors behind the girl, it’s really the right call for an aperture setting. [...]

  • Digital Vs. Film « Enlighten You Photography For Christian Teens July 21, 2011 05:44 am

    [...] pictures before you print them, and you really have to master your exposures, f-stops, apertures etc. to get the best out of [...]

  • Photography for Beginners – Part 2: Aperture | Day to Day Photo June 7, 2011 12:33 pm

    [...] Digital Photography School – Aperture [...]

  • Birthday Adventure | Photo Rookie April 2, 2011 11:08 am

    [...] had just started playing around with ISO, aperture and shutter speed in class so this was a good chance for me to have a go at seeing if I understood [...]

  • What is a 1.2 lens March 18, 2011 09:21 pm

    [...] explains aperture a little more. It's a really good site for learning, it's helped me quite a bit. Introduction to Aperture in Digital Photography Reply With Quote + Reply to Thread « Previous Thread | Next [...]

  • Photography is FUNdamental February 10, 2011 02:28 pm

    [...] of or behind the item you focus on is blurred), which in turn can be created by having a very large aperture. A low f-stop means a large aperture (yes, I know it makes no sense, but I didn’t design the [...]

  • H.W. numbah tuh « re-discovering my passion… October 15, 2010 11:54 am

    [...] For further reading: DPS Site [...]

  • Rock the Travel Portrait | imagine that June 17, 2010 05:08 pm

    [...] If you bring one on your trip, set it to Aperture mode when you intend to take travel portraits. Aperture is the size of the lens opening that allows light into the camera’s sensor, where the image is [...]

  • Day 2 – getting to know my camera begins! « Step by step photography May 23, 2010 08:58 am

    [...] smaller number of aperture is, the more blurry background is. This one I like the most so far, but still have no idea how to [...]

  • Link 1 « Gabrielenrique4's Blog April 6, 2010 03:14 am

    [...] Link 2 [...]

  • eTOC: Complete Beginner’s Guide to Digital Photography — My Blog March 21, 2010 12:50 am

    [...] and relationship between ISO, Aperture and Shutter Speed to obtain a good image’s exposure. Introduction to aperture in digital photography Darren ROWSE – Digital Photography School Explains that Aperture is ‘the size of the [...]

  • Correct Exposure vs. Creatively Correct Exposure » PhotoPatzer March 15, 2010 09:40 am

    [...] Digital Photography School – Introduction to Aperture [...]

  • Depth of Field: Why it ROCKS! » PhotoPatzer March 2, 2010 12:38 pm

    [...] Aperture is the hole located inside the lense.  This hole controls how much light is allowed through the lens, therefore allowing you to manipulate DOF.  For a longer explanation of aperture and how it works you can check these sites: Wikipedia: Aperture, Introduction to Aperture in Digital Photography. [...]

  • Camera Shake & Poor Focus | DSLR - Pentax Body February 25, 2010 06:00 pm

    [...] your shutter speed and the more light is available. If you’re in low light, opening your aperture to let in more light will allow you to quicken your shutter speed, but then you might have to [...]

  • Camera Shake & Poor Focus : DigiSolutions February 22, 2010 12:44 am

    [...] your shutter speed and the more light is available. If you’re in low light, opening your aperture to let in more light will allow you to quicken your shutter speed, but then you might have to [...]

  • John Wayne Hill : Blog – Digital Imagery as Social Mechanism February 18, 2010 03:53 am

    [...] In the online community DigitalPhotography School, ‘students’are given tutorials and lessons onphotography using example photosand accompanying text. I find thismethod to be very useful for simplephotographic situations. However,as the lesson becomes morecomplex, this method worksless and less. (image via Digital Photograph School) [...]

  • Beginner's Guide to using your new DSLR camera Part I | Featured January 27, 2010 05:01 am

    [...] One thing that causes a lot of new photographers confusion is that large apertures (where lots of light gets through) are given f/stop smaller numbers and smaller apertures (where less light gets through) have larger f-stop numbers. So f/2.8 is in fact a much larger aperture than f/22. It seems the wrong way around when you first hear it but you’ll get the hang of it. Read more: [...]

  • Day #9 « Findingnana January 9, 2010 07:00 pm

    [...] will notice that most of my pictures were taken at Aperture Priority Mode (I usually set at small numbers). Choosing a small number (large aperture) will [...]

  • Steps to follow to get the right snap everytime « Gautham Pai «» November 20, 2009 04:48 am

    [...] Aperture – What plane(s) do you want to capture, in other words the depth of the field. Do you want to blur out the background? Are you too close to the subject? [...]

  • How To Shoot Mountain Biking Pictures – MTB Photography – Part 2 | Mountain Biking by 198 November 9, 2009 10:43 pm

    [...] Speed: Aperture: ISO: [...]

  • Early morning in Lalbagh « Gautham Pai «» June 15, 2009 01:04 am

    [...] the past several weeks I realized the importance of aperture in the photos and I felt that a full manual mode gives me a lot of control over my images when [...]

  • Photography News, Digital Camera Reviews and more » Photography 101.5 - Aperture February 13, 2009 01:04 am

    [...] Introduction to Aperture - At [...]

Join Our Email Newsletter

Thanks for subscribing!

DPS offers a free weekly newsletter with: 
1. new photography tutorials and tips
2. latest photography assignments
3. photo competitions and prizes

Enter your email below to subscribe.
Get DAILY free tips, news and reviews via our RSS feed