This week, I thought I’d do something a little different… I know many people struggle with the basics of photography and using a DSLR – you have to start somewhere! Here’s a little info on aperture!
So firstly, the aperture is simply the size of the hole in which light is allowed through. The wider the hole, the more light is allowed in. Now this is where it gets confusing. (At least, it confused me at first!) The smaller the number, the wider the hole and vice versa. This means that an aperture of f5.6 is wider, and will let in a lot more light than an aperture of f18.
Aperture also controls the depth of field. This determines how much of your photograph will be in focus. Generally, the wider the aperture, the smaller the depth of field. Thus, a photo taken at f5.6 will have shallow depth of field, whereas one taken at f18 will have a larger depth of field. You can see this in the photos below! In the photos taken at f18, the fence is more in focus.
Now, in the photo below I’ve taken these shots with my kit lens. The fence behind the subject was around 3 metres away. All photos were done at 55mm focal length. The main difference is that the left hand side photos were taken from roughly 2 metres away, and the right hand side photos were taken from less than a metre away. You can see that distance also changes the depth of field.
A mistake that I’ve seen a lot (and I did it too!) is using too wide of an aperture. I got my 50mm f1.8 lens and used it on f1.8 for ages! However, doing so means that not a lot of your photo is in focus, unless you manage to get it right. Moving back and zooming in a little will help to get that shallow depth of field.
For example, this photo (yes, it is a chicken – bare with me xD) was taken at 214mm f9.0. You can see that it has a very shallow depth of field – the background is completely blurred. I think I was around 2-3 metres away from the chicken here… If I had taken it closer, and at 70mm, the background would not have been so blurred.
And macro – well, that needs a whole new post to attempt to explain about the very shallow depth of field you get. I try to stay above f8 for macro, although sometimes with the light available it isn’t possible. The snail photo was at f10, and the frog was at f6.3 so you can see that sometimes a wider aperture can work!
Well, I’m really bad at explaining things. I hope this was of some help to you, and if not, definitely comment with questions! I’m happy to answer anything you’re struggling with.