I've often commented, more is a Rant, that many teach "use a wide Aperture to blur the background" it's not false but only one third of the full truth.
- Aperture
- Lens Focal length
- Distance
With your variable focus length lens, a telephoto, focus on something say 30 feet away. Use your shortest focal length lens, widest Aperture. Take a photo. Without moving use a lounger focal length, focus on the same target. Take another picture.
What do the photos tell you?