Harmy said:
RotS is probably most stupid and least realistic lightsabres ever looked IMO.
I'll have to agree with you - however, I'm not talking about the sabers themselves. Just the glow they cast from behind the actors, which IS in fact realistic.
compare these photos
http://www.smashingmagazine.com/wp-content/uploads/2010/12/375.jpg
Notice how the glow of the backlight bleeds over the edges?
Now, look at this random screengrab from RotS (Sorry for low quality)
http://img16.imageshack.us/img16/6719/saberol.png
See how the bleed of the glow behind Anakin has a similar look to the actual photograph? That's what it really looks like when a light source is cast from behind an object.