Red Blasts, Painter's Servant, and Krosan Grip

[Kuma]

I was playing TEES versus Imperial Painter last night and this came up. My opponent had a Painter's Servant on the table naming blue. I had a Krosan Grip in hand and three mana open. If he tries to Red Elemental Blast or Pyroblast one of my not blue without Painter permanents and I Grip his Painter in response, what happens?

As I understand it, Red Elemental Blast only cares if the target is blue upon announcement, "Destroy target blue permanent." But would destroying Painter make the target illegal and remove the Blast from the stack?

Pyroblast checks if the target is blue upon resolution. So wouldn't my Gripping his Painter in response save my permanent?

[heroicraptor]

Targets are checked on announcement and resolution of a spell. That's why "shroud-in-response" type cards work. Both a REB and a Pyro would be countered.

[on1y0ne]

Targets are checked on announcement and resolution of a spell. That's why "shroud-in-response" type cards work. Both a REB and a Pyro would be countered.

REB is countered on resolution due to not having a legal target. Pyro says "...if it is blue" so it will just not do what he wanted it to do, but it is not countered.

[heroicraptor]

REB is countered on resolution due to not having a legal target. Pyro says "...if it is blue" so it will just not do what he wanted it to do, but it is not countered.

Well yeah, but the result is the same, barring absolute shit like Multani's Presence.