When you widen the aperture, the depth of field becomes shallower, and vice versa. That’s not all the Aperture does though, as it also affects the exposure. The DoF is also controlled by where you focus, and how far you are away from the subject.
Here’s a general comparison though. I focused close to the camera, which allowed for a shallower depth of field, and I narrow the aperture by one stop each step (which allows half the amount of light in). You should be able to see clearly as the depth of field changes.
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