What I Know So Far - Part One

This is the post where I begin filling you in on what I already know about photography.

Today's lesson is on the basics, which are aperture, shutter speed, and ISO.

The first and most important things I learned were the concepts of aperture, shutter speed, and ISO. What you need to understand is that there are three ways you can manipulate the settings on your camera, and those three ways involve setting the aperture, shutter speed and ISO.

So what do these elementary terms mean?

To be honest, I'm not entirely sure! I don't know what the inside of a camera looks like, and when someone tries to explain precisely how an aperture works I get really confused. But that doesn't mean I can't figure out how to use it.

So, we begin.

APERTURE

Take out your dSLR and turn it around so that you're looking the wrong way through the camera. Look closely into the lens, and you'll see a circle. Now, zoom in and out with the lens, still looking the wrong way through it, and you'll notice that circle get bigger and smaller.

This, my friends, is the aperture.

As you can see, it is the opening in your lens that lets in light. Common sense tells us that the bigger the opening is, the more light can get in in a smaller period of time.

The aperture allows light to get through that little circle and reach the sensor where the image is 'copied,' so to speak.

Apertures are measured in "f-stops", and will show up on your screen as f4.5, f11, f22 and so on.

Now, here's one of the most confusing things you will have to wrap your mind around. The largest apertures are the ones with the smallest numbers, and the smallest apertures are the ones with the biggest numbers. I don't know the calculation (remember, I said I get confused where apertures are concerned!) but I do know that the reason for this is that they are all fractions. So when I say f2.8 for one aperture, and f11 for another, in truth, that is f/2.8 and f/11. So just like how 1/2 is bigger than 1/10, so f/4 bigger than f/29. I don't know how else to put it.

Another confusing thing is the wording of said apertures. If I say you need a wide open aperture, then you need a large aperture. Remember, large aperture, small number. It means opening that aperture as much as you can.

I know, it's a lot to take in. Trust me though, once you've got it down, it'll never leave you. It's kind of like learning the multiplication table in elementary school. The task seemed so daunting at first, with so much to memorize, but once you grasped the concept and memorized each one, it was hard to forget because you used it over and over throughout the rest of your education. And you really will use this for the rest of your photography career.

Moving on.

SHUTTER SPEED

The sensor I mentioned earlier is always covered unless a picture is being taken. When you hit the shutter-release button (the trigger button, or the one that tells the camera to take the picture) the shutter opens and closes, letting light through the aperture for a short period of time. It would follow that, the longer the shutter is open, the more light can get through the aperture onto the sensor.

If you want an analogy to help it make sense, look at something around you and then close your eyes. Then open and shut your eyelids very quickly. You were only able to see a flash of what you were looking at, weren't you? Now try it again, except keep your eyes open for 3 seconds before closing them. You were able to take in a lot more this time, right? Well, that's sort of the way the shutter speed works, except with light. The longer the shutter is open, the more light the sensor is able to take in.

The shutter speeds on your camera are all in seconds or fractions of a second. For instance, 1/4 is 0.25 seconds, or a quarter of a second, whereas 1/500 is one five-hundredth of a second. So, much much faster. 1" is one full second, 2" two full seconds, and so on.

So, combine the aperture and shutter speed. If your aperture is very small (little opening, big number!) and your shutter speed is too fast, then you'll go to take a picture, but barely any light will get in, so your image will look all black (also called under-exposed), like so:


Conversely, If your aperture is really large (big opening, small number!) and your shutter speed is really slow, you'll let too much light in, and your image will look all white and washed-out (also called over-exposed), like so:


Photography is all about manipulating the settings to achieve the look you were going for. Sometimes you might actually want a really dark or a really washed-out photo, but usually if you're going for this look, you can achieve it through photo-editing, rather than with the settings on your camera. That way you don't lose information in the photo.

What does "losing information" mean? Well, take a look at that last photo. Everywhere you see white where there should have been colour means there was information lost. The camera took in so much light that it thinks everything is angelically white, and has not saved any information like, "green grass, blue water," and so on. That means, when you are editing this photo, you won't be able to make up the missing information.

ISO

ISO (sometimes referred to as ASA) refers to how sensitive the sensor is to light. The smaller the number, the less the sensitive the sensor. So an ISO of 100 is less sensitive than an ISO of 800.

There's more to the ISO definition than that, but in my opinion, it isn't important to know all of it. What you DO want to know, is how to use the ISO.

Keeping it at 400 is a pretty good rule of thumb. If you're shooting in broad daylight, it's a good idea to turn the ISO down to 100 or 200, and if you're shooting in low-light conditions, turning up the ISO may be a good idea. However, the higher the ISO, the more noise you get. You might not know what noise is by name, but I'm sure you've encountered it before. Here is an example of a photo with lots of noise:


Click on the photo, and you'll notice that the dark areas look a little fuzzy and speckled. Fortunately for you, noise isn't too big a deal on dSLRs, but regular point-and-shoots are always plagued with it. So don't listen to anyone who tries to tout a camera that can go up to 3200 ISO, because, honey, it just ain't worth it. It'll be the noisiest photo you've ever taken.

So there, those are the three essential terms where it concerns manipulating your camera. And with that knowledge, you'll be able to learn the next step, which involves finding the balance between the three components to have a well-exposed photo! If you have any questions or need clarification, post your comment in the comments section and I'll be happy to respond. :D

Until next time!