How aperture affects photos |Depth of field

When you learn photography, it is easy to get confused between the various modes on the camera.

I shoot on A aperture priority mode on my camera 99% of the time (see Aperture).The main reason I do this is because I don't shoot too much of action and sports and thus find no reason to switch to S, shutter priority mode. I also like  to control my depth of field or DoF as it is known. In easy terms, depth of field refers to how blurred out your background is, compared to the focus point. This is controlled by the aperture.

How aperture affects photos - Depth of field

To demonstrate this point, enter "The GMAX Team":

I shot the image below on an aperture setting of 1.8 on my camera. The camera automatically set the shutter speed to 1/160th of a sec.

How aperture affects photos

The focus is on Kai, the red Ninja. Notice, that though the difference between the team members is only inches - they have been arranged slightly one behind the other - the policeman, appears to be blurred. The focus gently blurs from Kai, to the policeman's handcuffs and the dog Tommy and Zane, the white Ninja are completely blurred.

For the next shot I changed the aperture setting to f4. The background is gradually beginning to come in focus. The policeman is happy now.

GMAX Studios-6080

 Let us stop down the aperture a bit more as in, make it smaller by stopping it down to f8. We see that  more of the background is coming into focus even though the main focus point still remains the same.

GMAX Studios-6082

If we make the aperture even smaller by closing it down to f11, the background is almost completely in focus.  The eyes of the white Ninja are almost sharp too. You can also make out the form of the chair at the dining table. which was not the case at all when we were shooting at f1.8. Also notice how the stitching on the dining table is in focus BEFORE and AFTER the focus point.

GMAX Studios-6084

For comparison, here is the first image shot at f1.8 again:

GMAX Studios-6079

Thumb Rule:

The higher the number of the aperture, more of the background will be in focus. This can be summarised by the graphic below.

Depth of field

You can download a hi-res version of this graphic to your computer or smartphone by adding us to your Google Plus circles. Also watch the video below to understand this concept better and see a practical demonstration of how aperture affects photos and depth of field. If you like the video, please consider subscribing to our channel by clicking here.

Shoot me your questions in the comments or leave your suggestions as to what articles or videos would you like to see next.

Subscribe to GMax Studios YouTube channel

Learn photography in one hour