Before changing anything structural, you can adjust your layout grid to naturally display the images slightly larger without needing a click.
In your theme customizer, click on the Product media block on the right side.
Change your Desktop layout setting from Grid to Stacked or Thumbnail carousel.
Turn the image zoom toggle Off. This removes the jarring full-screen popup entirely, and switching layouts will often format your pictures to be bigger and easier to see right on the main page.
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Based on your screenshot, the “Enable zoom” toggle in your current theme is hardcoded to use a full-screen popup (often called a lightbox). Because there is no dropdown menu there asking you to choose a “Zoom Type” (like “Hover” instead of “Click”), it means your theme simply does not have that slight on-page magnifying feature built into it.
To get that smooth hover zoom without the image taking over the whole screen, you have two simple options. If you prefer not to use any extra apps, you would need to hire a developer to add a small piece of custom code to your theme to change exactly how the image reacts when your mouse goes over it.
Hope this helps!
You’re using Tinker which is the same as Horizon, Savor, etc.
So you can search the forum for solution for any of those themes, like “Horizon product page image zoom”, I swear there were several recipes shared.
Can try something like in Theme settings-> Custom CSS:
ul.dialog-zoomed-gallery {
cursor: unset;
}
.dialog-zoomed-gallery .product-media-container--image {
margin:30px auto;
width:80%;
max-width:90rem;
}