I suppose the width and height aspect ratio should be preserved, however I was unable to experience the problem. If in the second control you are using I suppose only the image selector is used, but not the other selectors as well in the same control. Are you also experiencing the sam problem on a page that doesn`t use a theme without any additonal styling added to the page? To do this create a test page without template(start from scratch).
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items