Hello,
Yes, because it will be cut of to cover the slider area. Image comes as the background in this slider, so slider height does not depend on image size but on custom height settings or content height. In case you don’t plan to use any content http://prntscr.com/s3ends and just want to show the image with auto height then it would better to use the Image Gallery element with Nivo slider gallery type instead of the slider element.
Regards