By default the WooCommerce product gallery zoom image size is very big.  This can cause the zoomed image to look distorted and too far from the original.

The cause is that WooCommerce selects the ‘full’ image size to use as the zoomed image.

Use the snippet below to the use the ‘medium’ image size as the zoom image.  ‘large’ will give a bigger zoomed image.

// Change the image size used for the WooCommerce product gallery image zoom
// 'medium' or 'large' are normally the best options
add_filter( 'woocommerce_gallery_full_size', function( $size ) {
  return 'medium';
} );