Manual Camera Settings and the Exposure Triangle

If you’ve just picked up a camera and want to learn how to use it in manual or you’ve been using a camera for a while and want to take the next step, learning the exposure triangle is a must. Often I found when using my camera either fully automatic or even in one of the priority modes like aperture priority, the camera would either not properly expose the photo or certain settings would be automatically set to an unusable amount for what I was shooting.

This prompted me to learn how to use the manual settings of my camera within the first few weeks of owning my first DSLR. It can seem daunting at first, but I’ve found it to be second nature at this point. This allows me to know exactly how the photo will turn out before I take it, rather than my flow being disrupted during a shoot because the camera would improperly expose my photos.

To learn the exposure triangle, you must first know the fundamental exposure settings and exactly what they do.

Shutter Speed

I would say that shutter speed is probably the easiest of the three settings to learn. Shutter speed as the name suggests is the amount of time the shutter is open for. The longer the shutter is open relates to the amount of light that will enter into the sensor. I tend to change around this setting the most, especially during bright days.

Shutter speed tends to offer extra creativity in photos. To capture something with rapid movement such as a person playing sports or a bug erratically flying around you, the shutter speed must be raised. This means that the shutter will be open for less amount of time, say 1/1000th of a second, and thus less amount of light will enter the camera. To capture a scene where you want motion blur or need the extra light, you would lower the shutter speed. Scenes that often benefit from lower shutter speeds are landscapes with moving water such as rivers or waves, or Milky Way photos where you need the extra light that comes from having your shutter open for longer.

Lower shutter speeds are usually paired with having your camera on a tripod, as there’s a rule that states when using your camera handheld, any shutter speed less than double the focal length of your lens will introduce unwanted motion blur of the entire scene. For example, if you were using a 50mm lens on a full frame camera, you would want to stay above 1/100th of a second for your shutter speed in order to avoid motion blur and capture sharp photos.

Keep in mind that whenever you adjust your shutter speed, you would need to make sure your aperture and ISO are adjusted properly as well in order to properly expose your photo.

Aperture

Most photographers would agree with me that aperture is often set at one value and stays at that value. Aperture refers to the size of the opening of the hole in your lens, effectively allowing more or less light into the camera.

Larger apertures (<F/2.8) will let in more light and create a shallower depth of field, giving the smooth bokeh that every photographer craves.

Smaller apertures (>F/8) will let in less light and put more of the scene in focus.

Apertures tend to stay at the largest the lens will allow for as that is generally seen as being more favorable. With this, you’ll see that the main difference that separates lens prices are their maximum apertures. For example, the Canon RF 50mm F/1.8 is currently $200 new, whereas the Canon RF 50mm F/1.2 is currently $2,300 new. Whether those extra stops of light are worth it is up to you.

ISO

ISO refers to your camera sensor’s sensitivity to light. Raising the ISO doesn’t actually make the sensor more sensitive, but rather amplifies the effect of light photons on the sensor. Generally, you want to keep this as low as possible. Raising your ISO will increase the exposure but at a cost of adding noise to your images. In newer cameras, you can comfortably raise your ISO to 3200 before the noise starts to become apparent, but in some older cameras, especially crop sensor DSLRs, raising your ISO to even 800 can start to produce considerable noise.

If you can afford lowering your shutter speed or have extra F-stops to increase your aperture in order to correct your exposure, do that before raising your ISO. There are plenty of denoise software available to bring a noisy photo back to normal, but of course it is not something that should be relied on.

The Exposure Triangle

Putting all three of these fundamental settings together to create a properly exposed image, you get the exposure triangle. The exposure triangle is a visual showing how these settings all interact in a push and pull with each other. If the shutter speed is increased, less light will come into the camera, so either you must increase your aperture or ISO to make up for this.

You can think of it in terms of stops of light, where increasing the shutter speed from 1/125th of a second to 1/500th of a second will underexpose the image by two stops. To compensate for this, you must increase either your ISO or aperture by two stops, or you could increase both of these by one stop.

An example of this would be in that situation to either increase your ISO by two stops from ISO 200 to ISO 800 or increase your ISO by one stop from ISO 200 to ISO 400 and then increase your aperture by one stop from F/4 to F/2.8.

Conclusion

To sum this up, remember that every change you make in your settings must be compensated by another to keep consistent exposure. The only alternative to this is when your light source is changing, say the sun is going down. In that case there would be less available light and increasing the ISO would not need to be compensated by either shutter speed or aperture, as you increasing the ISO is the compensation for the sun going down.

The only way to really learn this though is to go out and try it. Switch your camera to manual and walk outside. Through trial and error and plenty of practice, you will be able to nail your exposure every time. Of course there is no shame in shooting in any of the automatic or priority settings, but for me I found that shooting fully manual gives me the full control and consistent shots that I’m looking for.

I hope this article was useful to you, and if you have any questions feel free to reach out to me via my contact page!