Darth Vader - Static or Dynamic character?

If you are talking JUST about Empire Strikes Back, its hard to tell. obviously throughout the whole six film saga, he is extremely dynamic. Unfortunately, we can't tell what he is thinking. If I had to say one way or the other, in Empire Strikes Back he is dynamic. At the beginning of the film, Vader had 100% complete allegiance to the Emperor. Is that allegiance shaken when he finally meets Luke at the end of the Movie? Is he starting to be torn between his son (which represents the love he shared with his wife) and the Emperor, the man responsible for his downfall, but also his prominent place of power? I would say yes. Empire Strikes Back marks the first step in Vader's road to redemption. A visual I can think of is a tiny, microscopic seed of light, buried deep, deep, within a enormous cloud of evil, destruction, regret, resentment, and hatred. The seed is buried so deep and is so small that Vader doesn't even know it is there. However, seeing Luke germinates this seed, almost without Vader and Luke's knowledge.