Image transformation of tif image does not work I use craft transformations for resizing images. The transformation of jpg files works as exepted, but the transformation of a tif image does not work. Imagick is installed and in the backend it creats and shows thumbnails of the images. When i rename the image from .tif to .jpg it performs the transformation also. 

The Twig code looks like this:

&lt;img src="{{ entry.getUrl('preview') }}" width="200" height="200"&gt;


The output HTML Code of a tif image looks like this:

&lt;img src="http://www.am-sb-coop.ch/internal/img/AM_HC16_KW00_Broccoli_rl_ZTG_DL.tif" width="200" height="200"&gt;

The output HTML Code of a jpg image looks like this:
&lt;img src="http://www.am-sb-coop.ch/internal/img/_preview/AM_FOOD_KW28_Prix_Gar_Konfi_mg_01_ZTG_DL.jpg" width="200" height="200"&gt;

Is this a bug or have i missed a config setting?

Here are some images for explanation:
I found the way to create thumbnails of tif files. You have to change the function isImageManipulatable in the file /craft/app/helpers/ImageHelper.php:

public static function isImageManipulatable($extension)
{
    $extensions = array('jpg', 'jpeg', 'gif', 'png', 'wbmp', 'xbm');

   if (craft()-&gt;images-&gt;isImagick())
    {
        $extensions[] = 'svg';
    }

    return in_array(mb_strtolower($extension), $extensions);

}


To this:

public static function isImageManipulatable($extension)
{
    $extensions = array('jpg', 'jpeg', 'gif', 'png', 'wbmp', 'xbm');

   if (craft()-&gt;images-&gt;isImagick())
    {
        $extensions[] = 'svg';
        $extensions[] = 'tif';
    }

    return in_array(mb_strtolower($extension), $extensions);

}


I know, changing core code is not a real solution: i posted this change as a Craft feature request -> http://feedback.buildwithcraft.com/forums/285221-feature-requests/suggestions/8794456-better-support-of-image-types-in-image-transformat