Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
In Program mode, when you meter a scene by half-pressing the Shutter button, the camera calculates an appropriate shutter speed and aperture, and maybe an ISO if you're set to Auto ISO. There will be times though, when you know that you're going to want a lot of control of aperture. Maybe you're shooting portraits, and you know that you want them to all have shallow depth of field, so you want to make certain that the camera is always using a wide aperture. Or maybe you're shooting landscapes, and that you want really deep depth f field in all of your shots, so you want to make certain that you're always using a very small aperture. Or maybe you're street shooting, and as you're moving around quickly, shooting different subject matter, you're changing your mind a lot about depth of field, and so you want to easily be able to change from a big to a small aperture.
In Aperture Priority mode, you can choose the aperture that you want and when the camera meters, it will automatically pick a corresponding shutter speed that will yield a correct exposure. To change to Aperture Priority mode, you just press the Mode button. I'm in Program mode right now. That's the big P. I rotate the main command dial until I am at A for Aperture. You can see the last aperture that was used in either Aperture or Manual mode. Last time I used either one of those modes, I set the Aperture to f/11.
The camera has automatically calculated a shutter speed of 1/640th of a second for my particular lighting situation here. To change aperture, I just rotate the subcommand dial. Going to the left gets me to a wider aperture; going to the right gets me to a smaller aperture, and you can see that it's recalculating the shutter speed every time I move it. By default, Aperture Priority mode works in third-stop increments. So to get from f/11 to f/8, I go one, two, three clicks. I can change that interval using a special customization feature that you'll see later.
Now, it is possible for me to pick an aperture that will leave the camera unable to choose a shutter speed that yields a good exposure. For example, I'm at ISO 6400 right now. If I open up my aperture all the way here, this lens will go to f/2.8. Now, you can see that at 3.5, I am at 1/8000th of a second. That's this camera's maximum shutter speed. If I go open one more stop, it starts flashing. And now, I've got a flashing 8000th of a shutter speed, and my Exposure Compensation Indicator has lit up, and it's showing me one-third of a stop of overexposure.
The camera will still take the picture, but it's warning me that that picture is going to be overexposed by a third of a stop. That might be fine for my subject matter-- a third of a stop might be something that I can easily fix in postproduction-- but the camera is just letting me know. If I back off my aperture, I'm now back to an acceptable shutter speed, and the display goes away. Aperture Priority doesn't allow you to take any shots that you couldn't take in Program mode using Flexible Program; rather, it simply provides you with a speedier way to get the aperture-based exposure settings that you need.
Get unlimited access to all courses for just $25/month.Become a member
164 Video lessons · 54292 Viewers
64 Video lessons · 86263 Viewers
86 Video lessons · 55705 Viewers
148 Video lessons · 93056 Viewers
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.
Your file was successfully uploaded.