The exposure triangleThere is no blog about photography that can escape this one. Like Sauron in the Lord of the Rings books had his one ring to rule them all, photographers are stuck with one triangle to rule them all. No matter how well equipped you are, no matter how much you studied, no matter whether you're a professional or just clicking away, this triangle will determine how your photos will look.
And what is it about? Light. More light or less light. And as we do not want black photos, nor white photos, we need to come up with something that sits in between there and in a way resembles the amount of light we had when shooting the photo.
Where is that triangle?It's everywhere! You cannot avoid it, every photo you make is faced with that triangle. However with the simple camera's or with smart phones you are not exposed to the exposure triangle. The camera will determine the settings based on what it determines to be the best. If you buy a more advanced camera, it will have knobs and buttons and you are supposed to make sense of these settings. The good news: these camera's also come with an "auto" mode. And the camera will in most modes (partially) control what is needed.
But most people did not buy such a camera to only shoot in auto mode. So, off you go to websites or books to learn about the three settings. These are called shutter speed, aperture and ISO. If you want some good explanations, just google exposure triangle and click on links. It is explained many times. And just to add yet another explanation, I'll add mine here too.
What is it all about?The above mentioned settings have different influences on how the photo looks, but they all have one thing in common. They influence the amount of light that reaches the sensor in the camera. So we need to tweak these settings so that we have the correct amount of light, and the secondary effects of these settings to give us the photo we want. And that means that changing one setting, will raise or lower the amount of light on the photo and to offset that, we might need to reduce one or both of the other settings.
Shutter speedThe first setting is shutter speed. And it determines exactly the... *drum roll* ... shutter speed! It opens the shutter for an amount of time, allowing light to reach the sensor. And then it closes the shutter. The longer the shutter is open, the more light. Can't get any simpler than that.
I hear you say: "But wait, what is that other influence this setting has then?"
Movement. If things in front of the camera move while the shutter is open, that will cause a blurred effect on the photo. So to keep everything sharp, you want a fast shutter speed. And that in return means: less light. Of course it is a bit depending on what you want to shoot. The racing car just whooshing along will surely need a much higher shutter speed to be seen as sharp than... oh well, the magnificent pebble laying on the path in your garden. Given the speed that the pebble moves, one can see that a shutter speed of hours would still leave it pretty sharp on the photo.
ApertureThe second setting is called aperture. It determines how wide the opening in the lens is. Obviously the wider the opening, the more light can enter. Now you start thinking: so I take a photo of that racing car mentioned earlier. And you know that to keep that sharp, you will need a fast shutter speed. Easy: just have a wide aperture. problem solved, we can go home. Right?
Not yet. This setting has also a secondary effect. Your super wide aperture that got the racing car super sharp, managed to get the tip of the car sharp. The rest is... well... blurred. Hey, you shoot: I had the fast shutter speed. Where is that blur coming from?
From your aperture. The secondary effect of aperture is called depth of field and basically tells the camera: I want only a small depth to be in focus, so blur the rest. Isn't this great? To get the whole car in focus and not blurred, we cannot use the widest aperture. We need to narrow the aperture. And thus we get less light on our sensor. Which brings us to our last setting...
ISOISO is the International Organization for Standardization and apparently that organization is housed in your camera. Or they have remotes and do complicated things from their offices to access your camera and influence your photos.
Okay, I admit: I never saw them in my camera, nor using remotes. So, the people working at that organization most likely do nothing. But they did define a standard about the sensitivity ratings for camera sensors. Quite useful actually, because we now can talk together and know we are talking about the same. Otherwise I am sure each manufacturer would have different ratings there. I guess by now you're stamping your feet and want to shout at me to tell you what it does. Or not, but if you did not: I will tell you anyway.
This setting determines, which you guessed already of course, the sensitivity of the sensor. The higher the setting, the more sensitive the sensor is. Making it work with less light. And that should solve our racing car problem. We just turn that setting fully upwards and then take the shot.
Isn't that beautiful? We have the motion frozen thanks to our high shutter speed, we see the full car without blur, thanks to our low aperture and thanks to our high ISO settings we see... what are those specks all over the photo?! Where did that come from?
Yes, you just found out the secondary influence of the ISO settings. The specks are usually called grain. And the higher the ISO setting, the more you get of it. Which is why in general the ISO setting is kept as low as possible.
How to make the perfect shot?I am going to tell you the secret now. You don't. If there was not enough light to keep the settings so you could have fast shutter speed, wide aperture and low ISO, you will need to sacrifice. And here comes your choice. I mean: do we really need to see the whole car and boarding along the road sharp? Perhaps we want to see the driver very sharp, the car a bit less sharp and the boards full of advertisement? Well, the boards do not need to be sharp at all. So, you can pick a bit wider aperture easily. And so you can make your choices. Perhaps you think a bit darker photo might be just the look you want.
As you see: you are bound by the triangle, but within it you are free to move as you want. You can pick how you want to have your photo look. And that is why not shooting in auto mode can be a good thing. Yes, in many cases the camera will pick good settings. But the camera does not determine what you want to show. It picks according to its internal programming.
You might not be forced to sacrifice, sometimes you choose to do that: you might want that smooth look from a waterfall that requires a longer shutter speed. The camera will never do that. You have that choice. And while you cannot escape the triangle that rules them all, you might well be able to make the triangle work for you to show your skill as a photographer. And should people tell you how great your skill is: tell me how you got there, so I might one day call myself skillful too. 😜