使用JQuery在模态弹出窗口上显示Php blob图像

Question

I've been trying to call a modal pop up

<div class="image content">
    <div class="ui medium image">
      <img style="max-width:400px;" src="" id="imgretprd">
      <br/>
      <div class="ui tiny images" style="width:500px;" align="left">
        </div>
</div>
</div>

Now in my html

<img id="imgretprdlist{{$product->productId}}" src="data:image/png;base64,{{base64_encode($image_prod->Blob1)}}"/>

I wanted to call the image that is retrieved here on the modal pop up above on my click function.

I tried using this code

  var ret_prodImg = document.getElementById('imgretprd');
    ret_prodImg = document.getElementById('imgretprdlist'+id).src;

But that's not working. It shows me blank only. Where am I going wrong?

Any answers to this will be appreciated.