Hi, welcome back to my photo tutor to our series of tutorials on using the Digital SLR and today we are going to be looking at how to use some of the other modes that we have on this. You remember we did that in our previous tutorial, we were looking at using it on fully program where you do not really do anything you let the camera do it all. But this time, we are going to look at the three other modes that are giving you control and then we will be focusing on one of them.

So we are going to look at the modes where it says M, A—might be AV, and then TV or on some cameras S. Okay so it might say M, which is Manual mode, which gives you the total control of the camera. You are deciding what shutter speed, you’re deciding what aperture to use. I will explain aperture again in just a moment.

Then we got AV or just A and that is the Aperture priority mode. And aperture priority simply means that you choose the aperture. So the priority is given to the aperture, you control that. And then the camera decides what shutter speed is needed to get the correct the exposure. And then we are coming back to that in just a moment.

Then we go to the next one which might say S on your camera or it might say TV. They are both the same thing. I will not bore with the details of why they call it TV, but this is the shutter priority mode. And so this is the opposite of aperture in that the priority is given to the shutter speed. You decide what shutter speed to use. For example, one 250th of a second, and the camera will decide what aperture is needed to give the correct exposure for that photo. Now we will talk more about the shutter priority in the next tutorial.

In this one, we are going to look at A or AV, which is aperture priority. Before we do that we need to say what is aperture. The aperture is just like the iris of your eye. The iris of your eye, which of course surround the pupil, the pupil is the black ball and it opens and closes. If you look at bright light, the iris closes down you got a very small aperture, small pupil—and aperture on the camera allowing a little bit of light to go through. But if you go into a dark room, it opens up to let more light through. And that is what the aperture is on your camera. It works in exactly the same way. So, if you were in a darker area you need a wider aperture. Now wider aperture is a small number on your camera. So a slightly backwards to what you might think.

A small aperture might be 2.8 or F4. We always call it F for the aperture number. And if you do that then you are going to get a nice wide open aperture, which is nice and wide allowing lots of light though. If however you choose one of the high numbers, maybe F16 or F22, then it is going the other way. It is going to make a very small hole allowing only a little light through. So obviously, it applies so you can do that because you don’t need so much light. That does makes a difference for something that we call depth of field. But that is something again that I’ll be explaining properly and showing you some examples of in another tutorial. But for the moment, what we need to remember is that we’re controlling that aperture.

And so, let us say we choose an aperture of F5.6. That is an aperture that you will have on your lens pretty much. Any lens is going to have that particular aperture. Some lenses of course have a minimum aperture of only about F4 sometimes even only F5.6. But this lens, this is sometimes known in the traders the nifty-50. It is a 50 mm and it’s at F1.8 which means it gets loads of light into the lens. And it is a very good lens to start with if you haven’t got a lens yet get one of these—the 50 mil nifty-50. It is a great lens and it’s not expensive. It’s one of the cheapest lenses you can get but it a great lens. Great for portraits and things like that.

Okay, so we have set it at 5.6. Now, we go to do our little half press like we have learned before. And we look at what shutter speed is chosen, and it might have chosen something like 125th of a second or 250th of a second. If I was then to move the aperture, if I was to open the aperture more remember that means the number goes down. So from the 5.6 if I went to F4 and open the aperture more, then the shutter speed will become faster because of course if I am letting more light in, then I only need the shutter to be open for less time to let the same amount of light through. And the same thing goes the other way. If I was to choose an aperture, which is smaller, then the camera will choose a shutter speed, which is longer open. So it might be 160 of a second something like that. So that it is allowing time for more light to pass through to the camera.

Now these are things that we can talk about a lot more, but remember when you get out there in a sunny day I would recommend that you start off with a middle aperture. And by that I would mean F8 or F11. If you start around about there, and if the shutter speed is too slow and to slow to hand hold, I would say it is less than 160 of a second. So maybe 130th of a second, then I would suggest that you need to open the aperture. So go try down to F8, and when you got to F8 have a look again. You will find that the shutter speed will have open up to a faster speed. If it gets to the 160th of a second, then great lets go for that. But if it’s still too slow, open it up a bit more, F5.6. And that is way we work. We are trying to get the maximum amount of light, but we are also trying to a get a speed that we can hand hold the camera. If the camera is opening the shutter for 115 to the second, you are going to find it very difficult to hold it very still for getting a really sharp picture and that is what we really want.

Okay, so start around about F8 or F11 and work from there. If it’s the shutter speed too slow then open the aperture go to higher number so that it will allow more light in which will enable it to have a faster shutter speed. And that is what aperture priority is all about. And in the next tutorial we are going to look at shutter speed priority. And the one after that, so that you know what is coming we are going to be looking at depth of field. So we are seeing how these work together in relationship.

So that is aperture priority for now. Hope you have understood that, but remember my phototutor.com is there for you. Come to the forum, write any questions you’ve got and we’ll be happy to help you out with a bit more knowledge if you need it. Okay, so go there and enjoy aperture priority mode on your Digital SLR.

My name is Rob Aaron, this has been my photo tutor.