Ok, so I see in your example that you are using the "slideshow" module. If you navigate to the samples folder in the panel /examples/gallery/slideshow/, you will find all the options for the slideshow module in the comments. On of the options "fit", decides how the image scales inside, and you can set it to "none".
# fit // Image scale method // [cover, contain, scaledown, none] : default cover
slideshow:[width],[height],[ratio],[nav],[fit],[transition],[duration],[captions],[loop],[autoplay],[interval],[startFullscreen]
drzylvon wrote:a simple slideshow in the welcome page but "smaller photos". So it's not in a slideshow box that comes from a click and where pictures wouldn't be stretched. It's just there in the background of home.
Sure. Personally, I am not a fan of this approach for X3 as a modern gallery, but that's my opinion. I don't like the empty spaces around the image, and the low quality 600px images look quite unimpressive on my macbook 13" 2880px screen.