Issue linking image to file

I'm trying to create a view that list a gallery of images and links them to a pdf. I've done something similar before were I would just link images to pages with a URL and all I had to do was just click on output this field as a link and it would display a path field to enter in the path it needed to go to. For what I'm trying to do, it doesn't seem to have the same result as when I try to link a image to a file path, the field doesn't display when I click on output this field as a link in rewrite results. Can anyone point out what i'm missing to do what I want to accomplish or any suggestions?

Thank you in advance.