<div id="slider-1" class="hidden">
<img src="images/image1" width="1920" height="1200">
<img src="images/image2" width="1920" height="1200">
<img src="images/image3" width="1920" height="1200">
</div>
var counter = 0;
$('slider1 img').each(function(){
$(this).isCaches() && $(this).isLoad()
? counter++
: 'Егор'
})