Watch the tech press the button as the he hooks up Artoo to the Rebel computer. He telegraphs the move with machine-like accuracy. Wow! He must have practised all night.
Ever notice that the computer schematics have the superlaser right in the Death Star’s equator? That’s was the original concept of the battle station, and a few Ralph McQuarrie matte paintings have been published showing it like that. The Star Wars Storybook has one, for instance.
A subtle effect during the Rebel briefing, Artoo’s the one feeding the data, the other Artoo (designated R2-X2 in the card game) is the one projecting. I’ve always loved his amazed whistle, as if he’s seeing the plans for the first time. We later see this green R2 being lowered into a X-wing. (He appears to be Biggs’ droid!) Note that in some distant shots, the other R2’s hologram light isn’t on.
Some things to spot. 1) Corellian Commander Bob Hudsol. 2) A number of Rebel officers in the crowd. 3) Wedge Antilles (sort of, see below) 4) General Jan Dodonna. 5) Commander Evram Lajaie. 6) Princess Leia Organa. 7) John "Dutch" Vander (Gold Leader) 8) Luke Skywalker.
There are two R5 units huddled near the back. One of them is the red and black unit assigned to Red Leader.
Okay, seated next to Luke Skywalker is Wedge Antilles, according to the script. However, that isn't actor Dennis Lawson, who would play Wedge in the cockpit scenes later on the film. It appears to be Jack Klaff, who is listed in the credits as John D. All published reports state that it is Wedge who utters the line in this scene, so it is generally accepted that the character seated next to Luke is Wedge, even though the actor is the guy who's supposed to play John D. Confounding matters even more is that Klaff's on-set dialogue is dubbed over by the actor who regularly supplies Wedge's lines.
In letterboxed versions of Star Wars, as Luke and Han have their exchange prior to the Battle of Yavin, Threepio and Chewbacca have a conversation in the background.
Since they only built one X-wing and one Y-wing, the part when Han says to Luke, "May the Force be with you" couldn’t have been shot sequentially. There are full-scale X-wings in both shots!
This scene reinstated in the Special Edition introduces Red Leader to Luke (and the audience). Red Leader is left nameless in the movie, but the novelization suggests his name is Dave. The card game states his name is Garven Dries, perhaps indicating that "Dave" is a nickname.
Personally, I never bought Lucas' story about the whole trilogy being carefully planned out and orchestrated. I'm more of the belief that he's making it up as he goes along. This scene with Red Leader was supposed to include the following line: "I met your father once when I was a boy. He was one hell of a pilot." Well, considering who Luke's father ends up being, this line elegantly edited out of the special edition, with most being none the wiser. However, eagle-eyed fans will spot the omission.
A Rebel technician is superimposed over the scene, allowing for the editors to jumpcut from one frame to another one, without the audience seeing the obvious edit. Looking carefully at the shot, you can see the characteristic contrast difference of the composition. The big giveaway is Artoo, however. Look carefully in the background and see how much Artoo rises in the span of time required for the tech to walk across the frame.
Generic helmets
During the montage scene, a whole bunch of Rebel pilots wear the same white and blue helmets. Lt. Wenton Chan is a Rebel pilot from Corulag.
The dramatic take off sequence, envisioned by Ralph McQuarrie in a production painting, is revamped in the special edition. The planet Yavin is now concealed under a layer of clouds, and we see the ships clearly rising from the base.