Hard to understand the recommended image sizes

I don´t understand your information on recommended image sizes for Catch Responsive Pro: Slider: Width: 1200px Height: 514px Featured Content: Width: 350px Height: 197px Featured: Width: 860px Height: 484px The featured image ALWAYS shows up at the top of the post, whether it will be used as an ordinary post, as a featured post or a post used in my slider! If I want to use the post as featured content and upload a 350 x 197 px photo that small photo appears at the top of the post. And if I want to use the post in my slider and therefore upload an image that is 1200 x 514 px it´s also appearing at the top of the post! So the dimensions 860 x 484 px should only be used in posts that I don´t want to use neither in the slider nor as featured content, but in a completely ordinary post? http://helensjoholm.nu/_eng/