Modify Existing Marquee Javascript .animate function to fadeIn and fadeOut / Opacity

Hello! I am fairly new to javascript-- I can understand it and change most elements, but I just really don’t know how to create my own scripts yet.

I am trying to modify this function to have the .marquee_photos fade in and then fade out. I had earlier changed the first .animate string to read

$('.marquee_photos').animate({opacity: '0'}, 1000); 

but all that did was fade the first photo out and now I do not know what the next step would be to have the next photo animate back in.

This is the original code without my above-mentioned modification:

// Animate photos and caption
	$('.marquee_photos').animate({left: newPhotoPosition}, 0);
	$('.marquee_caption').animate({}, 500, function(){
		var newHTML = $(newCaption).html();