     # If we want to refresh photos we can only count those we know they exist
     # in the blog. Any other file previously stored will never have a chance to
     # be downloaded again!
-    nbNewPosts = total if options['refresh-photos']
+    {startAt} = options
+    if options['refresh-photos']
+      if total < startAt
+        throw new Error "Starting at #{startAt} is above maximum blog photos #{total}!"
+      else
+        nbNewPosts = total - startAt
 
     if nbNewPosts > 0
       log.info "Processing #{nbNewPosts} photos on #{options.threads} threads.\n"

          else
            threaded start

      threaded options.startAt
    else
      log.info 'No new picture. If you want to force update, add --refresh-photos [-rp].\n'
      1


  process = (start, init=false) ->
    log.debug "Processing at #{start}...\n"
    # We know we only want photos and the maximum item size is 50.
    # These are not variables for the purpose of this tool, but could easily be
    # modified to download other stuff from a Tumblr blog ! :)
    api "#{url}?type=photo&num=50&start=#{start}"
    .then (parsed) ->
      # If we have a total number of posts and we are in the first loop, we are going to update..
