A Large Aperture or A Small Aperture?

A Large Aperture or A Small Aperture?

29 DEC, 2019 | BY YU CHENHAO

It is always a hesitation for new photographers on how to set the aperture when shooting various kinds of photos. If you are also facing this problem now, I hope this article can offer you some inspirations to expertly set the parameters.


What is An Aperture?

An aperture can be compared to a window. In a certain time, the amount of light is decided by whether this window is wide open. Professionally, as part of the exposure triangle (shutter speed, ISO, Aperture), aperture determines how bright or dark the image is. By changing the aperture setting, you increase or decrease the size of the aperture opening, letting in less or more light.

Apertures are measured in f-number. A wide aperture means a small f-number, like f/2.8, while a narrow aperture means a larger f-number, like f/16. The wider the aperture, the smaller the f-number.

But remember that the shutter speed and ISO should match with your aperture:  If you change the aperture by 1 stop, you’ll need to change the shutter speed or ISO by 1 step to compensate.


A narrow aperture will lead to:

  • Letting in less light which can help slow down your shutter speed and finish a long exposure, in order to capture the track of light or something fast-moving;

  • A bright light will be transferred into a scattered light;

  • A deep depth of field, ¬†while the foreground and background out of focus won‚Äôt be blurred.

For example, Sufficient light, shooting landscapes, shotting nighttime urban landscapes with tripod assisting.(f/8-11)


A wide aperture will lead to:

  • Letting in more light which can increase exposure and make the photo bright;

  • Increase in shutter speed;

  • A shallow depth of field, blurring out distractions in the background, drawing more attention to the subject, and creating bokeh.

For example Portraits, lack of light, a shallow depth of field.

How to choose? (In Av-mode)

  • Confirm perspective and composition.

  • Confirm depth of field: A deep depth of field or clear image with sharp lines.

  • Handheld or not: Pay attention to the slowest shutter speed under this situation, a wide aperture can help increase the shutter speed.

  • Moving subject or not: Moving subject needs higher shutter speed and a wide aperture.

  • Confirm the light situation. (refer to the explanation above)

  • Confirm your ISO according to the shutter speed. If it is slow speed under the certain aperture you need to increase the number of ISO.


Please contact me if you have any questions about photography techniques or our backdrops.

Leave a comment