Do You Want to Understand Your Frustrating Camera and Take Great Photos Today?


Watch this free video to...

  • End the frustration by adjusting just a few simple controls on your camera...
  • Make photography much easier, and look more professional too...
  • Remove all the complication & guesswork from using your camera...

Where should I send your video?

Do you want to understand your camera and take great photos today?

Yes Please

It dawned on me yesterday that I’ve written about shooting modes, and I’ve written about exposure, but I’ve never written about how and when you might use certain modes. Treat this topic as if you’ve just moved from full-auto or program mode, into aperture priority, and I’ll walk you through everything you need to know.

Full-auto mode allows you to change only the image format, and the burst fire mode. It will even use the pop-up flash if it thinks it needs to. Program mode is similar to a priority mode, in that you can change the likes of metering, white balance, etc., but you can’t change the shutter speed or aperture (you can change the ISO). OK, now we’ve seen the difference, lets have a look at what it can do.

When you switch to aperture priority, it does exactly what it says on the tin. The exposure gives priority over the aperture setting, and then shutter speed adjusts accordingly. Lets say that if you set the aperture to f/8, and the shutter speed is 1/200 of a second, and you decided to widen the aperture to f/5.6 (which allows twice the amount of light in), the camera will automatically change the shutter speed to 1/400 of a second to counteract for the extra light. This is how priority modes work. 

I use aperture priority mode about a third of the time (along with shutter priority and manual for the other two thirds), and it’s good for a number of reasons, the three main of which being sharpness, depth of field and light.

  1. When you widen the aperture to a lower number, say f/2, then you allow much more light into the lens, which allows you to speed up the shutter speed.
  2. Wider apertures also mean there’s a shallower depth of field and vice versa.
  3. When you narrow the aperture to around f/8-11 this is typically when the lens will be at the sharpest.

As you can see, there would be plenty of situations where you might want to use aperture priority over shutter or even manual. But what about all those people who say you should only shoot in manual? Well, they’re wrong. At least that’s my opinion. There’s plenty of cases where you might want to choose manual, but that’s only about a third of the time for me. Lets have a look at some of the situations where you would want to use aperture priority.

First though, I feel it’s worth mentioning an advantage that aperture priority has over shutter priority when it comes to exposure. A longer exposure will always allow more light into the lens, but not necessarily at speeds which will allow you to hold the camera in your hand. When it comes to aperture, it’s to do with the hardware of the lens, so if you buy one with a wider aperture, you can keep the shutter speed at handheld speeds, while widening the aperture to allow more light in. It’s a good way to improve the performance of your camera. 

When you should use Aperture Priority Mode

Situation 1 – Good light / Sunny day

When the light is fairly constant, you could use manual mode, but chances are that you’re just creating extra work for yourself. Why make the small changes that the camera is going to make for you? If you want to change the exposure, you can do so with exposure compensation meter provided in the camera.

When the light is good, you don’t need to worry about blurring your images because the shutter speed is always going to be fast enough to capture the movement. Particularly if the light is good. There’s an old rule ‘sunny 16’, which suggests a narrow aperture for shooting in the sun, and it really works. Just another reason to shoot in aperture priority.

In good light, you’re rich with light, so you might as well use a lot of it by narrowing your aperture to produce sharper images.

Situation 2 – Portraits

When shooting portraits, whether you’re using flashes or natural light, the lighting is usually pretty good. We tend not to make things harder for ourselves than they need to be, so comfortable lighting situations mean that we can take the photos at the aperture of out choosing.

I personally like to shoot at a range of apertures when taking portraits, but f/8 is one of my favourites. I just find that my photos come out the sharpest at this aperture, which works great for portraits.

Situation 3 – Landscapes

Landscapes typically have a foreground and a background, and often a middle ground too. To see all of this in focus, you need a wider aperture, somewhere up to about f/16 works for me. There are times where I will use a tripod, and if I am then I might use manual mode, but more often than not, I’m using my camera handheld so aperture priority works fine as I’m not playing with any longer shutter speeds. This is where depth of field becomes really important.

Situation 4 – Shallow Depth of Field

Shallow depth of field is achieved by opening up your camera’s aperture, which allows more light in at the same time. It’s not a small amount more light either, it’s a lot more light. The jump from f/2.8 to f/1.4 allows four times more light in, which can easily be counteracted by the shutter speed automatically, in aperture priority mode.

When you change the DoF, chances are you will be experimenting quite a bit, so you’re just giving yourself more work if you’re using manual mode. It’s not all about manual mode.

When you Wouldn’t Use Aperture Priority (But think you might)

Situation 1 – Poor light / Darkened room

As I mentioned before, the beauty of a wider aperture is that it allows your camera to see more light, and this is especially true in a darkened room. But that doesn’t mean you should select aperture priority mode. I find it best to use shutter speed priority. Let me explain…

When you’re in low light, the two main worries are about exposure (not getting enough light) and camera shake (blurry pictures). If you set the camera to aperture priority then you’re only really dealing with half of the problem, which is light. When you’re in shutter speed priority, you can account for the camera shake (say, 1/30 or 1/50 of a second) and the aperture will adjust around the speed to produce the exposure. 

Even if there’s not enough light, the aperture will automatically go to it’s widest, and you can play with the photo in post production. At least that way you don’t have a blurred photo, which you can’t fix (yet).

Situation 2 – Night Landscapes

I know I mentioned above that I like to shoot landscapes in aperture priority mode, and this is true, but not when I’m shooting at night. Night photography is a different game, reserved for the likes of manual mode. The lighting becomes so unpredictable, you have to make calculations and estimations in your head, it’s really more a case of trial and error.

How & When to Use Aperture Priority Mode

A note from Josh, ExpertPhotography's Photographer-In-Chief:

Thank you for reading...

CLICK HERE if you want to capture breathtaking images, without the frustration of a complicated camera.

It's my training video that will walk you how to use your camera's functions in just 10 minutes - for free!

I also offer video courses and ebooks covering the following subjects:

You could be just a few days away from finally understanding how to use your camera to take great photos!

Thanks again for reading our articles!


Hey I'm Josh, I'm Photographer in Chief here at ExpertPhotography, and I'm in charge of making sure that we provide you with the best content from the most knowledgeable photographers in the world. Enjoy the site :)

  • I see some good points in this article 🙂 I personally use aperture priority most of the time. In most cases I need to control depth of field and so I set aperture as first control.

    Im using ISO 100 or 200 in good light. When the shutter speed gets too slow, I raise ISO but only to necessary level.

    If I need fast shutter speed, I simply set aperture to acceptable minimum and raise ISO if necessary. This is in my opinion far better then camera changing DOF as it wants. I usually try to avoid fully open lens, most lenses needs to be stopped down 1/2 or 1 EV to avoid really soft results.

    I do not shoot in fully manual mode except night shots. Many folks advice to use manual mode but I see no reason why it is necessary.

  • Larry

    Josh, Another Great article. Love your site, very informative. I have had my Canon T1i for almost 2 years, and I am still intrigued by what this camera can do.


  • Kris

    Hi Josh. I’ve learned a lot from this article. Thank you very much!

  • Dave

    Changing light is really the only time I use aperture priority mode. Otherwise, Aperture priority mode and manual seem to do the same thing just in different ways.

    In aperture priority mode:

    If I frame my shot and I have the good fortune to have my spot meter pointed at a mid tone, then (and only then) I can rely on the camera choice of shutter speed (unless I feel confident that the camera’s matrix metering will give me the right exposure — which I usually don’t). This is the only time for me that Aperture priority is faster than manual as the camera actually picks the correct shutter speed in this case.

    If I am not metering off a midtone then the camera will not pick the correct shutter speed and I have two choices. I can point the camera and a midtone, let the camera choose a shutter speed, hit ael, and recompose.


    I can use exposure compensation based on the lightness or darkness of the tone I am metering off of. So instead of moving the shutter speed dial, I have to fiddle with the less ergonomic exposure compensation buttons to do the same thing (change shutter speed).

    The latter two procedures aren’t any quicker than pointing the camera at a mid tone, zeroing out the meter and recomposing.


    Framing and changing the meter with the shutter speed dial an amount based on the tone you are taking a meter reading off of.

    Manual mode also makes it easier to check that your highlights aren’t blown out by simply pointing the camera at the highlights and checking to make sure the meter is not more than +2.

  • Harry11

    @Kris @Dave Hey!
    Whenever I use aperture priority mode my pictures becomes so blurry…Can You give me some advice?

  • JamesSargent2

    When I first started shooting DSLR, I read a blog by a housewife turned photographer and she put everything out there so plain and simple.  Looking back now, one piece of advice she gave was to stay in aperture priority, because it was so easy.  Most of the pictures she took were outside of her kids.  That’s basically what I started with, but have moved on to more complex lighting situations.  Even with indoor low light situations, I was sticking with Av and setting my EV -1 to -2, ISO 800-1600, then fixing my exposure in post.  After reading this, I am definitely going to try shutter priority indoors to see how it compares. Thanks.

  • JamesSargent2

    Harry11, what kind of camera and lens are you using?

  • All of this is really just silly. No matter what mode you are in the result is the same. If you want control you need to add the third part of the triangle which is ASA.
    i use a different approach after some fifty years of experience in the darkroom and digital, to wit:
    Pick your output determinant – i.e. Print size
    Set An ASA that will give good results at that print size
    Pick an aperture that gives adequate depth of field but avoids diffraction – again relative to print size
    Look at the shutter speed and adjust either of the other two exposure compromises to acheive a motif
    Visualize the motif and set exposure comp to get the desired motif into zone 5 of the meter.
    Program mode does this for you, but Manual mode is easier, in Manual just read the exp comp off the scale, you don’t need exp comp button.
    Also if you stay in manual mode, each subsequent frame will have a similar lighting effect and you don’t need to readjust anything unless the light changes, or you visualize a scene diferently.
    It is really way to easy