The triangular engine section in the Lars garage is, obviously, the skyhopper. Watch as Luke plays with the model. When he puts it down, he breaks its stand, and tries to (subtlety) fix it.
Not a mistake (although some fans claim it’s a blooper), watch Threepio as the hologram appears. He jumps from one platform to another.
Where does the rag that Threepio uses to dry himself go? Keep an eye on it.
According to behind-the-scenes material for the Star Wars Special Edition, most of the original elements from A New Hope composite shots were preserved, so that they could be digitally recomposited. It would seem that not all the elements were salvaged since Artoo's animated hologram light is missing in this shot of the Special Edition.
Luke's removal of the restraining bolt is accompanied by really simplistic, hand-animated sparks.
There is a blue treadwell droid wandering in the background. Cybot Galactica manufactures the WED15 units as general purpose machinery maintenance droids.
When Luke says "It’s a whole ‘nother year" you can hear birds in the background.
Shelagh (Aunt Beru) Fraser’s voice is painfully dubbed over, particularly in the Hif Fi Pan & Scan and THX versions. I’ve heard rumors that is was changed because she had too heavy an Irish accent or that her dialogue was too soft-spoken on location.
The juice container and cup that Luke uses during supper keep switching hands. Watch for it.
The Special Edition sharpens the matte on the lowermost of Tatooine's twin suns. In the original, the upper curve of the sun becomes blurry. In the Special Edition, the sun and foreground clouds keep their focus.
The planet Tatooine orbits twin G1 and G2 type stars. They are designated Tatoo I and Tatoo II. The light reflected from Tatooine's sodium flats is so intense that early explorers dismissed the world as a lesser star.
As Luke runs out of the garage to go find Artoo, the camera pans with him, following him until he stops to look out with his macrobinoculars. Then Threepio walks out. Threepio was in the garage, right? Well, not if you look closely at the "hut" that Luke emerges from. As he exits and runs past, you can see Threepio’s shadow on the hut, meaning he was already outside. This is out of frame on the pan & scan THX copies.
The Tatooine sky changes in color depending on whether it’s a close up of Luke and Threepio or a medium shot. This illustrates the pressures of time when shooting at twilight. The Special Edition corrects this mistake by replacing the darker sky with a lighter one.
2X-K3PR (Tooex) is a simple Lerrimore maintenance and diagnostic droid. Owen Lars employs this unit to activate the security screens and perimeter lighting on his homestead.
In the first morning shots of the homestead courtyard, the WED15 treadwell droid is tucked away in the foyer on the left hand side of the vaporator cluster. As Owen walks into the shot, the droid has moved the opposite side.