I've done a computation of the movement of Barnard's Star over the 1 year, from 20 July 2011 to 20 July 2012, and derived a figure of 10.3075 arc seconds.
The method used was to superimpose the two images (which I took 1 year apart) precisely, and then compare the 2 positions of Barnard's Star against the distances between 4 nearby pairs of stars. The distances between those 4 pairs were obtained from TheSky6 planetarium software.
Thereafter, it was a rather straightforward process of measuring the various distances on my PC's screen with a ruler.
Perhaps that is a bit simplistic? Anyway, the workings are:
Pair 1: 409" = 124mm; Pair 2: 98" = 29.5mm; Pair 3: 90" = 27mm; Pair 4: 82" = 24.5mm
Average of 4 pairs: 1mm = 3.325"
Distance moved by Barnard's Star in mm on PC screen (centre to centre): 3.1mm
Distance moved by Barnard's Star in arc seconds: 3.1mm x 3.325" = 10.3075".
And my figure of 10.3075" indeed corresponds with the published value of 10.3"! (See for example: http://en.wikipedia.org/wiki/Barnard's_Star)
Below is an annotated superimposed image of the 2 positions of Barnard's Star and that of the surrounding stars used in the computation.
And further below is an improved animated GIF which I've made using the free Photoscape software, based on the same two images. (Note: the animation might not run on all platforms/software).
http://i.picoodle.com/858j6zdq

http://i.picoodle.com/8a5j6zea
