Images resized during slideshow despite option being disabled

I think this is the 2nd or 3rd time that I've mentioned this. I was hoping that it would be addressed in the newest version, but it doesn't seem to be.

Images are resized during slideshows even though the optioin to resize is deselected. This can have a huge impact on image quality.

Also, I've noticed that the area of the screen allocated to the lightbox seems to be too small - why resize when there is masses of space both above and below the frame still available for use?