I know this is long today, but there’s just so much to cover here. I could easily spend an hour talking about the aperture without repeating myself. It’s basically what makes photography possible. I’m sure I’ll return to it in the future, but this should get you started.

daniel

Transcript:
Hey photographers. Daniel Roberts here for FreshEdgePhoto.com. Wow! Today we have got a dusy. I’m going to try to explain apertures in just a couple of minutes. Call it the aperture, call it the iris, it’s that thing inside your lens that keeps light out or lets more light in.

Wow… There’s so much here to cover. Basically the aperture controls a lot of things. In a sense it’s an inverse relationship with your shutter speed. The more you shrink down that aperture and make it tight, the more you have to lower your shutter speed and vise versa. Raise your shutter speed, open the aperture.

Well, here’s the deal too. The reason that expensive lenses cost so gosh darn much is they have a lot of glass in them. They’re very big around. Now the length is obviously somewhat controlling the focal length (telephoto or wide-angle), but the diameter of the lens is how much light it’s letting in for that focal length. So, if the focal length is a 1:1 relationship to the width, then you have an f/1.0 lens. Now, Canon made one in the 50mm length a while back, and they’re really expensive because they don’t make them anymore. Now is there that much difference between an f/1.0 and an f/1.4? Not really to me, but at the same time, that’s also a lot more light.

Now, the way they multiply is very odd. This has something to do with pi and squared and all that math stuff. There’s f/1.0 because we have to start somewhere, then halfway between f/1.0 and f/2.0 is f/1.4. 1.4 is the square root of 2. Anyway, if you can remember f/1.0 and f/1.4 you’ve got the whole range covered more or less. So, there’s f/1.0 f/1.4 f/2.0 f/2.8 so on and so forth down the line. Now later on it gets rounded off with f/11 and f/22. Thankfully they don’t make us remember all the little “.” here and there.

Now that you’ve got that, it will let you know that every time it increases it doubles the amount of light or halves the amount of light when it decreases in number. Actually I just flipped that around. See, apertures are very confusing, even for me.

The wider you can get it, the nicer you get that bokeh, that shallow depth of field that lets you get this blurry background behind me. That’s also controlled by other factors that we’ll get into later.

That’s kind of the rundown for apertures for the day. I generally shoot as wide open as my lenses will let me because I love that blurry background. If you’re shooting landscapes, obviously you don’t want to do that because only part of it will be in focus. So, that’s basically what you have, and I hope that’s helpful. You can take that to the bank. My name is Daniel Roberts for FreshEdgePhoto.com. You can find more of me there. Thank you.