All About Aperture

So you want to learn about aperture? First off, we're gonna have to start with what part of the lens the "aperture" actually is. When you look into your lens past the layers of glass you'll be able to see several triangular almost ocean wave shaped pieces of metal that form a hole; these are called "blades." They move in and out to make the hole in the middle smaller or larger which in turn controls how much light is let into the camera.

Blades closed and open

Controlling how much light that comes into the camera is crucial because it 1. makes the image brighter (duh!), but more importantly 2. it effects how the focus works. The wider you have the aperture the softer the image looks (the shallower the focus is) and the smaller it is the sharper it looks (the deeper the focus is). You'd tend to use a smaller aperture for wider shots, like landscapes/cityscapes or if you want everything in frame in focus, (shots like this often let a lot more light in as well which helps balance out how bright the image is). You'd use a wider aperture for shots where your zoomed in to a subject like when taking portrait shots or when doing macro photography extremely close up to small objects, (in these cases having a wide aperture also allows more light in which once again helps balance the image out as it would be to dark with a smaller aperture without adjustment in camera).

F-Stop

The "F-Stop" are the set of numbers on the lens that tell you how wide or small your aperture is. Now contrary to what you may think when first looking at the numbers on your lens, the lower the number is the wider the aperture is and the higher the number the smaller it is, for example the smallest the lens in the image above can go is F/22 and the widest is F/1.7. Knowing what F-stop to use and when to use it can be incredibly important for certain types of photography instead of just eyeballing it, for example when doing long exposures of moving objects such as traffic or the stars you'd need to work out what F-stop your lens needs to be set at in conjunction with the camera's shutter speed and ISO as the image could end up either being far too over- or under-exposed if not done correctly.

A fairly easy way to figure out what aperture to use with what shutter speed is the double half method. In basic terms if you double the shutter speed, you'll need to compensate by halving the aperture, and vice versa if you double the aperture you'll need to half the shutter speed. So let's say you have your aperture set at f/5.6 and your shutter speed at 1/500, and you want to double your shutter speed to 1/250 then you'd half your aperture to f/8, or if you wanted half your shutter speed from 1/500 to 1/1000 then you'd need to double your aperture from f/5.6 to f/4.

(The aperture numbers go in the sequence 22, 16, 11, 8, 5.6, 4, 2.8, 1.7 so by halving f/5.6 you'd go down one number to f/8, and to go down by one quarter instead you'd go two numbers back to f/11).

That's where I'm going to leave it for now, this should hopefully give you a basic idea of what aperture is and how it works, I’m not going to get into how you’d work out ISO into the equation as that’s a completely different kettle of fish and it’s more based on the situation you're in than a standard set of settings. If you have any questions on any of this, or if you want to suggest what I should write about next either message me on here or shoot me a tweet at @NPSTUDIOS_LTD.

Thanks for reading.