Checking if Image file exists before displaying it?

I want a page to display an image for a record if the image file
actually exists. If the file does not exist (newly created record) I
want the placeholder image to display. I’ve tried using File.exist? as
my conditional but it fails to find the files that do exist. Any ideas
how to easily handle this at the view code level?

View Code:

<% for e in @media_elements %>
<% if File.exist?(e.filename) %>
<%= link_to(image_tag(e.filename.to_s) -%>
<% else %>
<%= link_to(image_tag(“placeholder_image.jpg”) -%>
<% end %>
<% end %>

It was a path issue, just provided some more info on the full path to
the image and the File.exist? method worked just fine. Sorry for
wasting the space.