My 'Big Screen Edition' of TF2 arrived from the US (thank you third party sellers through Amazon!).
I haven't watched the entirety of the film yet (I saw the standard Blu-Ray at my brother's place last week) but the IMAX footage can be found in the forest fight and in the scenes with Devastator.
The
entire forest fight is in IMAX mode, i.e. the picture expands to film the whole screen and it looks positively gorgeous. This is also the place where most of the extra footage is - seconds worth scattered throughout, but very noticeable. Nonetheless it integrates seamlessly with the action in the 'normal' cut, which is to be expected given it isn't some sort of crude director's cut add-on.
The most noticeable part of the extra-footage is Grindor's participation in the fight - in the normal version he does pretty much nothing except fire once (missing) - getting hit by friendly fire from Starscream, and then trying to stab Optimus with a knife he keeps in his leg before getting his faced rip apart by Optimus' energon-hooks.
In the IMAX version, just before the sequence where Megatron kicks Optimus' face in (and then he and Starscream go to town on him, sending him flying) Grindor gets in on the action, grabbing Optimus by the head with one hand and then using his helicopter blades as a melee weapon to stick them into his sides. Optimus then elbows him in the face.
There are several more extended fighting shots in the scene, but it's hard to explain where they start/stop and where the 'standard' action starts/stops. But you will know it immediately when you see it if you've seen the original film recently. They're both before Optimus' "I'll take you all on!" moment, and after.
There may also be some extra footage in the Devastator IMAX scenes, but I'm unsure. There is a very cool easter egg of a newspaper getting stuck on a pipe that Mudflap & Skids are holding onto before Devastator's vortex - G1 Shockwave is on it, it's a newspaper robot about an alien sighting according to the Interwebs.
Other easter eggs I've heard of but haven't' yet seen are R2-D2 and the T-1000.
Basically, if you want to get this film on Blu-Ray and you have the option, definitely get the 'Big Screen Edition'. It won't cost you any extra and it's got more robot action porn.
Other random non-comprehensive observations:-
* It's definitely a clone of Bonecrusher (or Bonecrusher himself?) who kills one of the Arcees. A protoform Decepticon gets the other one in the same shot;
* Three (IIRC) protoform Decepticons are seen getting hit / possibly destroyed by the B-1B JDAM airstrike;
* Mixmaster goes into a Galvatron-style "artillery cannon" mode when he transforms to fire at US armor - separate from his robot form and his cement truck form. This is just before Jetfire cuts him in half and then tears his head off;
* Megatron's fancy arm cannon behaves like a series of sequentially timed explosive charges when it hits the ground
* The level of detail on the robots when they're damaged is just unbelievable. Megatron is so fucked up after Optimus shoots him through the wall of the ancient ruin that the tank treads on his feet have been torn off.
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- PeZook
