Hi! I am Yuukon, and I am a photographer. Today I am here to tell you all about lighting in photography!
If you are new to Photography 101, you can check out chapter one and two here:
Photography 101: Chapter 01: Basics - Looking
Photography101: Chapter 02: Composition - Location
Chapter Three: LightingThere will be several subjects coming to light (no pun intended!) in this chapter today. Some of these things will be directly related to chapter one of this course, where we talk about basics and terms in photography. If you forgot what something means, check back there to find the explanation.
Subjects we will talk about:
- - Aperture
- - Shutter Speed
- - ISO
ApertureIn chapter one we discussed the basics of what aperture does and means. Today we will be going a bit deeper on that, to help you understand what you can do with aperture and how it works.
Aperture is an adjustable hole in the lens opening that lets the light pass through. This is what an aperture looks like:
Aperture & Light
Most (cheaper) lenses have a 5 or 6 bladed aperture. In the analog times, the lenses mostly had more blades because, from what my grandfather told me, with the mechanics, blades were a lot easier to control and fix than with the electrical apertures today. My grandfather taught me how to take apart old lenses and fix them myself, which I occasionally do for hobby purposes. It has really helped me in understand how apertures work, which will hopefully help me explain this to you today.
Here is a little schematic:
( Click to open! )You might recognize this from chapter one, where I used a similar schematic. In chapter one we talked about how a lower number gives you a wider aperture, while a higher number gives you a smaller aperture.
If your aperture is wide, on a low number, it means a lot of light will be able to reach your film, or sensor. This is ideal in circumstances where there is little light, like for instance, at night, inside or during dusk or dawn. Even on cloudy days a lower aperture is going to allow you to work with more light.
You can compare aperture to a running tap. When you open it all the way, a lot of water is coming through. But the further you close it, the less water comes through. It’s the same with aperture and light.
Aperture is the same on all lenses. If I were to set one of my analog lenses on aperture stop f/8, it would let the same amount of light through as if I were to set one of my digital lenses to aperture f/8.
Most lenses show what the biggest aperture they can do is. Take a look at the image below:
This lens has a focal length of 50mm, which is comparable to what the human eye can see. The letters EF indicate which lens mount these are suitable for, and the “II” means that it is the second version Canon has created of this lens.
Now, the “1.8” stands for the widest aperture this lens can do, and 1.8 is pretty wide! Most cheaper lenses have a widest aperture of f/3.5. The f/1.8 means this lens can let a lot of light in.
With zoom lenses, this often works a bit different. If we take the Canon EF-s 18-55 mm kit lens, for example:
As you probably figured, this lens lets a lot less light in than the 50mm lens does. However, this does not make this a bad lens. If you aperture does not give you the amount of light you need, there a more way to get more light on your sensor.
Aperture & Depth of Field
Aperture however isn't just there to control light. Aperture also controls “depth of field”. This is something we have also briefly discussed in chapter one, which you might remember.
In chapter one we said that, the wider your aperture, the smaller your depth of field will be. If you take a smaller aperture, you will have much more depth of field.
This is something I've also showed you with my duck back in chapter one.
A shallow depth of field, which goes with a low number and wide aperture, is great when you want your subject to separate from the background. A shallow depth of field means your background gets nicely blurred, which puts the attention on your subject, like in this photo of my duck at aperture stop f/1.8:
Shutter SpeedAs mentioned above, a wider aperture means more light, and a smaller aperture means less light. This directly relates with the shutter speed you use. With the duck pictures, for example, I had to take a very fast shutter speed when using f/1.8, to compensate for the enormous amounts of light coming in from my studio light, even though I had set it to it’s lowest setting.
However, when I took the picture at f/22, I had to slow down my shutter speed, because even with the studio light at maximum, I couldn't get enough light in.
Shutter Speed Explained
Back in chapter one, we went to Wikipedia a couple times. Let’s do that again:
“Shutter speed or exposure time is the length of time when the film or digital sensor inside the camera is exposed to light, also when a camera's shutter is open when taking a photograph. The amount of light that reaches the film or image sensor is proportional to the exposure time. 1/500th of a second will let half as much light in as 1/250th.”
So, shutter speed is also referred to as “exposure time”, which might explain the term a bit.
Your camera has a shutter, this is basically a curtain that goes up when you press the shutter release button. Once this curtain goes up, the light, and thus the image in front of the lens, will reach the sensor.
Compare this to opening your own curtains in the morning. When you open the curtains, you can see out of the window what’s happening outside, and daylight reaches you. When you close them, you can’t see outside, and the daylight does not reach you.
Now of course we can’t open and close our curtains at the speed our camera lifts up the shutter, but it’s a good metaphor.
Shutter speeds vary in time. When I look at my own camera, the fastest shutter speed it has is 1/8000 of a second. This is VERY fast. This is so fast, that I have never even used it because it wouldn't let enough light pass through to capture anything.
The longest shutter speed my camera has, is 30 seconds. You’ll need a tripod to be able to use that setting.
Let me explain what you can use different shutter speeds for:
1 - 30+ seconds: These longer shutter speeds are very useful when you want to take photos of the night, or capture moving car lights at night, for example.
2 - ½ second: This is good to add a soft look to flowing water in landscape photos. You need a tripod for these speeds as well.
½ - 1/30 second: These speeds are useful to add motion blur when photographing a racehorse or any other moving subjects. These can be done holding the camera by hand, or placed on a tripod.
1/50 - 1/100 second: “normal” photos under normal light circumstances, no tripod needed.
1/250 - 1/500 second: To freeze a moving car or other moving subject, hand-held with a big zoom lens, greater than 250mm.
1/1000 - 1/4000 second: To freeze extremely fast subject motion.
Of course, you can also let the shutter speed depend on how much light you have available. On a bright, sunny day, you’ll likely be looking at shutter speeds ranging anywhere from 1/500 second to 1/4000 second. On a cloudy day, shutter speeds between 1/30 second and 1/160 second are more likely.
In short: A faster shutter speed, means a shorter exposure time, because the shutter (curtain) opens and closes much faster.
Shutter Speed & Aperture
Shutter speed and aperture relate to each other directly. They work together to get the desired exposure on your photo.
Sometimes, when I am out shooting landscapes, I notice I need a greater depth of field. Which means I close my aperture, so there is less light coming to my sensor through my lens. This is something I need to compensate by using a slower shutter speed, so the sensor is exposed a bit longer, giving me the extra light I am now missing from the aperture. Here’s a little table:
Photography is all about getting the correct amount of light to hit your sensor. At f/22, which is a very small opening, a lot less light will hit the sensor compared to a picture taken at f/1.4, which is a very big opening. Keep in mind, that this is assuming the shutter is open for the same amount of time.
However, you can get the same exposure at f/22 as you can get at f/1.4, simply by lengthening the shutter speed, which causes the shutter to be open for a longer time, which allows more light in. Aperture and shutter speed settings combined allow the amount of light you need to pass on to your sensor.
Different combinations of shutter speeds and apertures, as in the table above, can give you the same amount of light in a photo.
For example, when looking at the table above, f/16 at 8 seconds, will give you the same amount of light as f/8 at 2 seconds. This is known as “equivalent exposure”.
ISO SpeedThe ISO speed determines how light-sensitive your image-sensor is to incoming light. ISO is something that’s best kept low, to prevent it from creating noise on your images. Even though noise can be easily removed, it often results in losing (a lot) of detail, so it’s always best to avoid it!
I've found that the best ISO speeds for my camera are between ISO100 and ISO800. When the ISO goes above 800, noise gets too prominent. This limit differs per camera, so it’s very important to know what your camera's “limit” is. A lot of camera’s can get their ISO speed as high as 12800, or even higher, however, these are numbers that create a lot of noise.
A few examples, which I have use in chapter one as well:
ISO100 ISO3200 ISO8000When taking a look at these images, you’ll notice that the first, which is at ISO100 is clear. The second is ISO 3200,. which, as you can see, creates a lot of noise. This is still okayish, though. And it might not always show up as much as in this picture. The last one is ISO 8000. This is a limit you generally don’t want to touch.
( Click on each photo to open! )
( Click on each photo to open! )
A lot of post-processing software have built-in noise removal tools. There are also a lot of free noise removal tools, in case yours doesn't have it built-in.
You can find some on my Photography Resources List, these are all free.
Remember, a low ISO is almost always better. If you can’t use your aperture or shutter speed to create more light, ISO is kind of like a last resort.
I've said this before, but, lighting is very important in your photograph. Like composition. In photography it’s very important to know what the three elements in this chapter are for, what you can do with them and how to utilize them in a way that benefits your photograph.
In the next chapter I will tell you all about working with (different) light-sources.
If you have any questions, please ask!
If you have suggestions for my course, send me a note!
If you want to learn more about photography, and receive feedback on your work, check out PhotographyGuide!
Photography 101: Chapter 04: Light sources and WB
Photography 101: Chapter 05: RAW and Basic Editing
Photography 101: Chapter 06: Gear