Add class to image in view
If .myclass img { your code goes here } is not good enough and you must have the class inside the img tag, then:

1) Download and enable the Image URL Formater Module

2) On your view's picture field, select url as format.

3)

Option A) In the rewrite results field type &lt;img src="[field_image]" class="yay-we-did-it"&gt;  

Option B) if you want to use the .tpl.php file, put this inside it.

&lt;img src='&lt;?php print $fields["field_image"]-&gt;content; ?&gt;' class='yay-we-did-it'&gt;