title: Photoshop script ignores transparency on saving into png (Mac OS)
body: <p>For example I have a project with two layers. First layer is transparent. Second layer has a rect and its opacity is 50%.</p>
  
  <p>After saving in a saved file the picture looks like as the opacity was 100% (fully opaque). How to solve this? I used the following function to save:</p>
  
  <pre><code>function SavePNG(saveFile){
      var opts = new ExportOptionsSaveForWeb();
      opts.format = SaveDocumentType.PNG;
      opts.PNGB = false;
      opts.quality = 100;
      pngFile = new File(saveFile);
      opts.includeProfile = true;
      app.activeDocument.exportDocument(pngFile, ExportType.SAVEFORWEB, opts);
  }
  </code></pre>
  
  <p>I used photoshop cs6</p>