Image Slider is does not support retina

Hi

Image slider does not support retina images. Moreover, it uses only full-size images.
I do need to make a slider of 10 images with 6000x2000px (image load time ;/ ). I need to set size for them for ‘large’ or even ‘medium’. Can you help me doing it?

When image size select will be available for Image Slider as a part of VC?