The Camera- Aperture and Iris

 

What is aperture?

What aperture controls is how wide or narrow the opening of your lens is while taking a photo. You can shrink the lens with a higher aperture allowing less light to enter or expand it with a lower aperture allowing more light to flood in. This has a direct effect on exposure and depth of field.

A picture I took with a very low aperture demonstrates the bouquet effect.

How does aperture affect exposure?

By changing the amount of light entering your lens you affect the exposure of your photo every time you change the aperture. With a higher aperture, your scene will be darker and with a lower aperture, your scene will appear more bright.

These two pictures I took with the same lighting
 but with different apertures demonstrating its effect on exposure

how does aperture affect depth of field?

Aperture is very important for its ability to change the depth of field.  Using a large aperture and closing your lens to a smaller size creates a higher depth of field and makes the background and the object of focus very clear. using a smaller aperture leaves the iris wider and makes the subject that you are focusing on far more clear than the background.

picture of me with low aperture

picture of me with high aperture

How do you pick the right aperture for your scene?

When selecting the right aperture for a scene you have to manage the two factors that it affects, exposure and depth of field. If you are looking for a darker scene you could use a higher aperture to get proper lighting, but other factors such as shutter speed can be changed to cancel this effect if you want to adjust your aperture without changing the exposure. For depth of field, you have to decide if you want select focus and simplicity in the background of the subject or a scene where everything is in focus.

Photo taken with low aperture for the sake of simplicity

photo taken with high aperture to show the distance of the landscape

What is Iris and how does it affect exposure?

Iris is what controls how much light enters the lens and therefore can increase or decrease the exposure of a scene. It can be set to automatically change it while a scene is moving or manually. the changing of the iris can prevent the subject from appearing overexposed or underexposed.

 My clips showing aperture and select focus