Photos in views taking a long time to load We have  views  with  multiple  cck image  fields  http://screencast.com/t/UOGxa9Jr6  with  'Group multiple values'
And  we have a theme  function  to add the needed  classes for a script to display these photos in fancybox 

function mytheme_content_view_multiple_field($items, $field, $values) {

  if($field['field_name']=='field_photos_images'){
    $output = '';
     $i = 0;
    foreach ($items as $item){
      if(!empty($item) || $item == '0')
        {
          if($i == 0) {

            $output .= '&lt;p&gt;&lt;a class="" data-fancybox-group="thumb"  href="/' . $item . '"&gt;&lt;img src="/' . $item . '" alt="" width="200" height="150" /&gt;&lt;/a&gt;&lt;/p&gt;';

          }
          else {
            $output .= '&lt;p&gt;&lt;a class="hid" data-fancybox-group="thumb"  href="/' . $item . '"&gt;&lt;img src="/' . $item . '" alt="" /&gt;&lt;/a&gt;&lt;/p&gt;';
          }
          $i++;
        }
    }
    return $output;    
  }
}


each node has many images so it takes some time for the nodes to load, you can see each image load one by one taking about 10 seconds to complete
If you can see the images loading one by one then this doesn't have anything to do with the View rendering slowly.

Slow running PHP generally means you have to wait longer before anything displays, not that individual parts of the page render slowly.

Slow loading images means the file size is large or you have a bad internet connection between you and the server.

You've mentioned that you're using CCK so I assume you're using Drupal 6.

Might I recommend using imagecache to pre-process the images to be scaled on the server to the right dimensions before they are sent to the user.

http://drupal.org/project/imagecache

Instead of printing the image tag directly, setup an imagecache preset in Drupal then you call theme() to generate the image markup.

Example:

&lt;?php
  print theme('imagecache', 'mypresetname', 'path/to/file.jpg');
?&gt;


Documentation on the theme function can be found here: http://drupalcontrib.org/api/drupal/contributions!imagecache!imagecache.module/function/theme_imagecache/6