How did the Keplerian Refractor, proposed around 1611, improve upon the Galilean design?

Answer

It offered a wider field of view and better magnification

Johannes Kepler quickly recognized the limitations of Galileo's initial configuration and proposed an alternative design utilizing two convex lenses instead of the mixed objective/eyepiece pair. While this Keplerian design resulted in an image that was inverted (upside down)—a drawback for terrestrial use—it offered significant advantages for purely astronomical work. Specifically, the arrangement with two convex lenses permitted the construction of instruments with a much wider field of view compared to their predecessors, alongside achieving higher levels of magnification. This superior optical performance made the Keplerian design the preferred standard configuration for serious astronomical observation until reflecting telescopes became practical.

$How did the Keplerian Refractor, proposed around 1611, improve upon the Galilean design?$

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