ok I have checked the names and now have.

Imagetest.php

<?php

class Imagetest extends DataObject
{
   static $db = array (
      'Name' => 'Text',
      'Description' => 'Text',
      'Category' => "Enum('Industry, Finance, Education')"
   );
   
   static $has_one = array (
   'ImagetestPage' => 'ImagetestPage',
      'Attachment' => 'Image'
      
   );
   
   public function getCMSFields_forPopup()
   {
      return new FieldSet(
         new TextField('Name'),
         new TextareaField('Description'),
         new DropdownField('Category','Category', singleton('Imagetest')->dbObject('Category')->enumValues()),
         new FileIFrameField('Attachment')
      );
   }
}

?>

ImagetestPage.php

<?php

class ImagetestPage extends Page
{
   static $has_many = array (
      'Imagetests' => 'Imagetest'
   );
   
   public function getCMSFields()
   {
      $f = parent::getCMSFields();
      $imagemanager = new ImageDataObjectManager(
         $this, // Controller
         'Imagetests', // Source name
         'Imagetest', // Source class
         'Attachment', // File name on DataObject
         array(
            'Name' => 'Name',
            'Description' => 'Description',
            'Category' => 'Category'
         ), // Headings
         'getCMSFields_forPopup' // Detail fields (function name or FieldSet object)
         // Filter clause
         // Sort clause
         // Join clause
      );
$f->addFieldToTab("Root.Content.Imagetests",$imagemanager);
return $f;
   }

}

class ImagetestPage_Controller extends Page_Controller {

}

?>

and

ImagetestPage.ss

<% if Menu(2) %>
<ul id="Menu2">
<% control Menu(2) %>
<li class="$LinkingMode"><a href="$Link" title="Go to the $Title page">$MenuTitle</a></li>
<% end_control %>
</ul>
<% end_if %>

<div id="Content" class="typography">
<% if Level(2) %>
<div class="breadcrumbs">
$Breadcrumbs
</div>
<% end_if %>
      
<h1>$Title</h1>

<% control Imagetests %>
$Description
<% end_control %>

$Content

</div>

I dropped the imagetet table and rebuilt database.

Now when I click on Imagetest page in CMS it does not load at all?

why would this work for filedataobjectmanager and not image one?

Is there anytutorial on specifically the imagedataobjectmanager?