SW Saga: Deflect/Block question

[Talya]

Do you declare you are blocking or deflecting an attack before or after the attack roll is made?

In other words, do you know the DC you are trying to beat before you make your deflect roll? (So for instance, if it's going to be almost impossible to block, you can choose to negate energy instead.)

Please source your answer. I've already read the text of the particular talents involved and they don't directly answer this question.

[TheThan]

I say before, during your turn you declare it. think of it like dodge.

Otherwise you can get hit with the time traveling syndrom:

DM: you take xd6 damage from the stromtrooper’s blaster rifle.
Player: no I don’t I declare my saber block ability for it.
DM; but you didn’t declare it before I rolled the dice,
Player: yeah, I know I’m declaring it now, so that attack gets blocked and deflected back to the trooper!
DM: thwacks player with heavy object

[Talya]

I say before, during your turn you declare it. think of it like dodge. Not only does this not have the source I asked for, but it's actually wrong, by RAW. You do not have to declare reactions prior to your turn.

You certainly have to declare block/deflect before damage is rolled, however.

[Mando Knight]

It's a reaction, so I'd say that the Deflect or Block is declared after the attack roll. Also, the DC of the Block/Deflect = the attacker's attack roll.

Think of it cinematically. The Jedi always twitch their lightsabers after the shot is fired in order to intercept it. The attack roll is the blaster being fired, the UTF skill check is the twitching lightsaber.

I think that it's between the (otherwise successful) attack roll and the damage roll that the player has to declare it. I see it this way: Stormtrooper, say, TK 829, fires at the Jedi, say, Luke Skywalker. TK 829 attacks with a natural 20, bringing him up to an attack roll of 24 and an automatic hit, barely enough to overcome Skywalker's dodging abilities (Reflex 26, but natural 20's an auto-hit). Luke, seeing through the Force that he can't dodge the bolt, uses the Force to guide his lightsaber, twitching it upwards slightly with a UTF check of 30. The bolt bounces off of the lightsaber harmlessly. (Well, not quite. Luke, as he's twitching the lightsaber, realizes through the Force how much he needs to move it to redirect the shot at the trooper (Redirect Shot talent), and succeeds his attack against the stormtrooper, killing him)

[Starbuck_II]

You declare block after attack or before you chice, but must be made prior to DM telling you result (which is translated to DM describing attack or hit/miss).

But you should ask him to tell you number of rol before declaring. As this can be before damage.

You can block fail that roll than attempt negate energy after damage though. These are different reactions. You can react to more than one stimuli in a round.