What is a common practice for pre-focusing a zoom lens?

Pre-focusing a zoom lens is commonly achieved by zooming in and focusing on the target object. This technique allows the operator to ensure that the focus is sharp on the subject of interest. When the lens is zoomed in, the depth of field is typically narrower, making it easier to achieve precise focus on a specific point. Once focused, the operator can then zoom out to the desired framing without losing the focus on the subject.

Using automatic focus settings may not be reliable in all situations, especially in dynamic environments or with complex scenes where autofocus might struggle to lock onto the intended subject. Adjusting the zoom to the maximum length can result in a change in focus and depth of field, which might misalign the focus when returning to a wider shot. Employing a specific aperture setting can impact the exposure and depth of field but is not a direct method for pre-focusing in a typical workflow.