This particular ronto replaces a green and white R2 unit that crosses past the shot.
Rontos are huge pack animals domesticated by the Jawas. Rontos have
excellent olfactory senses. They have heat-shedding membranes on the side
of their head which also serve as eye protection during sand and gravel
storms. The ronto is a redress of the brachiosaurus digital topography
used in Jurassic Park.
The hovering Imperial probe droids can trace their origins to early Ralph McQuarrie paintings of Mos Eisley which included seeker remotes that kept order in the city. This particular droid is nicknamed Face, though its proper designation is IM4-099.
Note that this stormtrooper's "headband" is riding up, indicating it is little more than a detachable costume dressing.
This particular ronto replaces a couple of human and droid extras in the background.
George Lucas named the ronto after ILM artists suggested they had better
stop calling it by its deign nickname of "bronto."
1) A team of ASP droids marching to work.
2) Luke's landspeeder clone travelling in the opposite direction.
3) An immense crashed ship that not only upstages the remains of the Dowager Queen, but also provides shade.
4) A pair of tethered rontos
5) A CG redress of Luke's landspeeder, this time with one thruster.
This particular ronto replaces is tethered to a human extra who, 20 years ago, had no idea he'd be taking a saurian giant on a "walkee."
Note the extreme difference in picture quality from the original and
the Special Edition. This was one of Lucas' most hated shots of the original.
The original had a sloppy animated haze meant to cover the speeder's wheels.
Because of the limits of photochemical compositing, each effect shot degraded
the original picture to some degree. In contrast, the new composite was
achieved digitally, with no picture loss, allowing for a very clean image.
Mos Eisley was founded around the remains of the original colony ship, the Dowager Queen. The crash site memorial still adorns the center of the city. It is largely infested by Jawas now.
In the Special Edition, the site moves around from local to local. Note the addition of an Imperial shuttle to this scene, flying in the background. Its distinctive engine hum can be heard on the soundtrack.
An enclosed speeder developed by Bespin Motors, the TX-3 is also known as the Void Spider, for its leg-mounted repulsor-pads. Note that a shuttle variant exists called the Void Spider THX-1138.
A note the ronto in the background, a nice bit of continuity by ILM artists.
The extra leading the way into the cantina is ILM animator Steve "Spaz" Williams. He is wearing the Weequay vest from Return of the Jedi.
Watch as Threepio nags Artoo to "come along" into the cantina, an extra walks by with unkempt dark hair, a tan long-sleeve shirt, and by the looks of it, Han’s pants. Dark blue with the Corellian bloodstripe.