Ajax error when importing to an image field

I have local install of drupal and I have the images in the public dir. all I want to do is get the file name for each image in to the file field called "Photo" for the content type Article os it will show as the thumbnail.

What's the proper way to format the field? Do I have to include path inf as well as the filename, and if so, what would be an example of that.

right now with just the file name I'm gettingthe following error:

An AJAX HTTP error occurred. HTTP Result Code: 500 Debugging information follows. Path: /batch?id=81&op=do StatusText: Service unavailable (with message) ResponseText: Recoverable fatal error: Argument 2 passed to token_replace() must be an array, null given, called in /Users/dougrose/Sites/feedsimport/modules/file/file.field.inc on line 581 and defined in token_replace() (line 79 of /Users/johns/Sites/feedsimport/includes/token.inc).

Thanks.