Feature Slider Selection: Optimal Image Size

RE: Infinite Photography Pro Version 3.0.1

>>Customize >>>Featured Section Options >>>> Feature Slider Selection

What’s the “ideal” horizontal image size and vertical image for these 5 images?
e.g. Horizontal Orientation W” x H” and Vertical Orientation W”xH” (or in pixels)

We’re finding the default crops in ways that are not desired. Is it possible that by using all the exact image size, it will not crop?
Example: yellow car’s rear cropped – https://dbiela.com/galleries/gallery/automotive/

Thanks