So i'm trying to set an image as a background, and the image source is pulled from a variable. I've tried different methods from the setAttribute to src= ect. Can you guys tell me what i'm missing?

Here is my html code i'm trying to set the image too i've tried with the img tag not having the src in the tag to start as well still nothing:

```
    <body onload = "mapThing()">
        <img id = "elephant" src=''>
        <canvas id="processing"></canvas>
    </body>

```

here is the function that has the setAtt elements in it:

```
   function mapThing(){
    mapUrl = getValue("urlValue");
    var backImg = parseUrl(mapUrl);
    console.log(backImg);
    function setBack(){
    document.getElementById('elephant').setAttribute('backImg', 'src');
   }
    setBack();
   }

```

the backImage is a url in the form of:
<http://maps.googleapis.com/maps/api/streetview?size=600x600&location=40.736315,-73.992243&fov=75&heading=23.58&pitch=10>