Printing fields in a View template file (Devel / Krumo)
You not using the correct Views template, views-view.tpl.php is the base template. You need to use views-view-field.tpl.php but you need to use template overrides in your theme.

Firstly, copy views-view-field.tpl.php from the Views module into your theme, make a copy of views-view-field.tpl.php calling it views-view-field--field_image.tpl.php and make your adjustments, remember to clear your template cache so Drupal picks up these files.