AF-On Button


Canon® EOS 77D Fast Start


Lesson Info

AF-On Button

Next up is we have an AF on button. And this is one of the few buttons on the camera that is really pretty much useless when you get the camera straight out of the box. Because what happens is the camera will focus when you press that button but when you press the shutter release the camera will refocus because the camera focuses when you press down on the shutter release. Now a favorite feature among a lot of serious photographers is rear button autofocus, or back button AF. And this is where you separate taking pictures from shooting photos and so some people prefer to use the back button to focus and then once it's in focus then they're gonna decide on the timing of their photographs. And in order to do this, you would use the AF on button but you have to turn off the autofocus on the shutter release button. And the way that you do that is by going on to set up menu number four, custom functions and turning off the autofocus option. And I know a lot of you who are getting this camer...

a kinda wanna use your camera in a more advanced mode so let's go ahead and do that right now. So I'm gonna dive in to set up menu number four. Go into the menu, set up menu number four and there's custom functions and I am currently forgetting which one it was. I thought it was towards the end, number 14. And so here we have the option and I'm gonna press the set button and we have different controls on the camera and it's actually showing you what buttons. We'll talk more about this later but what we wanna control is the focusing of the shutter release. So I'm gonna hit the set button to enter here and our options are metering and autofocus. Just metering start or autoexposure lock so it locks the exposure and I typically don't wanna do that. This is the way the camera comes standard, metering and autofocus. And I want this one, metering start. So I'm gonna press the set button. Metering on the shutter release button. So now, let me see if I can do this in live view so you can see what's going on. So let's get my little subject here in the foreground. Back up a little bit so that we can see what's going on. And so, if I, let's see, we are in autofocus, good good good, and make sure we're right about here. And so let's change our focusing point to something a little bit more specific. And so when I press down and take a photo, you can clearly see that it's on the bananas and they are out of focus (camera clicks) and the camera is gonna let me take a photo that is out of focus. Let me change this to a little bit shallower depth of field just so we can see what's going on. (camera clicks) So when I take a photo, it is out of focus, because the bananas I did not focus on. So now with back button focusing, I will focus with the back button and then I can choose to take a photo. (camera clicks) And if I wanna recompose maybe to something right here where the focus point would be in between it might have a hard time focusing, I don't need to refocus because I know I already focused on the bananas. (camera clicks) And I can just set the focus there. Now maybe I wanna focus on the lens. And so I'll press the button in the back of the camera. It's in focus. I'm gonna recompose cause I want this composition right here and I can take a photo and even though the focus point is on an area that I don't want in focus, that I don't care about, (camera clicks) I've been able to isolate what I want in focus and then recompose and shoot photos. And so for anyone who's getting into fairly serious photography, I would highly recommend that you experiment with back button focusing. Not everyone loves it. But I will say that if you watch CreativeLive photography classes, and you watch some of the more advanced classes, where they're shooting portraits or lighting in the studio and they talk about their camera set up about 95% of them are gonna talk about using back button focusing on their camera. It's because it's a very good tool for people who wanna have very specific control of what they're shooting. But it's your option on how you set that up with the camera. But that is how you do it. Next up is the autoexposure lock button and this will lock the exposure so as you move the camera from side to side, it maintains the same exposure. So let me show you on my camera. I'm gonna leave it in aperture priority and let's turn on the info screen so that you can see what's going on. And so right now I'm choosing F4 and the camera is choosing a 30th of a second but if we were to pan around, and in fact let me zoom in just to make this more extreme, if I move the camera around you're gonna see those shutter speeds constantly changing cause the camera is reading the different light that it sees. If I wanna lock any particular number in, I'm gonna press that asterisk button right up here and it's gonna stay locked in. And let me see if I can, I can release my finger, and so now I don't have to leave my finger on it. I can just move it around, take the photo. And now when I come back, it's still locked in. I can press it in again and lock it in on any sort of new subject that I wanted. So if you have a subject, say it's standing, say you have a person standing next to a very bright window and the bright window is throwing off your exposure. You can move the camera over a little bit to where the person is, lock the exposure in, move the camera back to, include the window and now the exposure is gonna be for the person without the bright window throwing the meter off. And so it's a good system to work with in program, time value, and aperture value. It's not really gonna be of use in manual because you're setting your exposure settings on your own. But in those other modes, it is a way of working. Now, different people will have different systems. Some people will use exposure compensation. Some people will use exposure lock. Some people will switch over to manual exposure. They'll all be able to achieve the same result. It's just a matter of which way you like to work with. And so some people use this button. Some people don't use it at all and if you don't, well you can possibly reprogram that to do something else. Alright next up is our AF points button. We talked about this earlier and so if you wanted to move one of the focusing points, one of the easiest ways to do it is to hit that thumb button and then use the cross buttons on the back of the camera, the up down and left right, to reposition the focusing frames someplace else.

Class Description

We know what it’s like to dive right into taking pictures with your new camera. But trying to understand the manual can be a frustrating experience. Get the most out of your new Canon EOS 77D with this complete step-by-step walkthrough of the camera’s features.

Join expert photographer John Greengo for a fast-track introduction, and unlock your camera’s full potential. In this Fast Start class, you’ll learn:

  • Learn about the best settings for the new 45-point AF system including several customization options
  • New Interval timer and bulb timer options for creative options
  • 14 custom setting options for personalizing your camera

John is a CreativeLive veteran instructor and an experienced photographer. He has extensive experience teaching the technical minutiae that makes any camera an effective tool: aperture, ISO, the Rule of Thirds, and the kinds of lenses you’ll need to suit your camera body. This Fast Start includes a complete breakdown of your camera’s exposure, focus, metering, video and more. John will also explain how to customize the Canon EOS 77D settings to work for your style of photography.


Nikita Sokolsky

Must have for all 77D owners. Thanks, John!

Dara Pkyprek

Hello, is it hand-on practice or just show how to use the menu in the camera, plz B.R Dara

John Greengo