Make loaded svg invisible in snap.svg

I have loaded my svg image, but now I want to make it invisible. And I can't find a way to do it ...

var snapObj = Snap("#svgElement");
var group = snapObj.group();
var svgImage;

Snap.load("../img/image.svg", onImageLoaded);

function onImageLoaded(f) {
    svgImage = f;
    group.append(svgImage);
}

So now I need to know which attribute of svgImage I have to change the visibility of the image to false.