export - Manipulate to GIF

I am using the following example code to export Manipulate to GIF:

ManToGif[man_, name_String, step_Integer] := 
 Export[name <> ".gif", 
  Import[Export["f:\\test.avi", man], "ImageList"][[1 ;; -1 ;; step]]]

man = Manipulate[Plot[Sin[x], {x, 0, end}], {end, Pi, 2 Pi, 0.1}];


ManToGif[man, "f:\\test", 1];

Is there another possibility to do that? How can I see the value of the variable end?

You see at bottom of the movie some strange black bars and also at the right edge a black vertical line, which should not be there.