console.log() showing contradictory values for the same object property

I think i might be going mad.

I use console.log() to see the state of an object and then on the next line do a console.log() on a particular property of the same object and get different values for each.

The code i'm using is:

console.log(this.pictures.Items[pic].val);

for(var i in this.pictures.Items[pic].val) {
    console.log("property: %s, value: %s", i, this.pictures.Items[pic].val[i] );
}

and firebug outputs:

Picture { isLoaded=true, isSelected=false, img_src="imgs/image1.jpg", more...}

property: isLoaded, value: false
...more properties

as you can see, 'isLoaded' is true when logging the object itself but false when logging the property.

I have tried logging the object again after just in case, and it is true again.

Does anyone know what is happening here?

Thanks

Rich