Zoom Lenses

This is from a Facebook query.

There are two types of zoom lenses. One has a fixed or constant aperture and the other has a variable aperture. The fixed aperture zoom will remain at the aperture you set no matter where you set the zoom.

The variable aperture zoom varys the aperture depending on where you set the zoom. This is a cost-saving method. So aside from being more expensive with an aperture that doesn’t move from where you set it this zoom also does not unexpectedly affect or change the exposure as you zoom in and out.

So while amateur photographers buy less expensive (and often lighter and cheaper made) variable zoom lenses not caring (or even being aware) that the exposure is changing as they zoom as it does not affect their image a wedding photographer who must have the white in a wedding dress look exactly the same from shot to shot regardless of how zoomed in or out pays the price for a fixed aperture zoom.

To answer your question yes on a constant aperture zoom you can set it to any aperture setting knowing it won’t change anything while you’re shooting.