Ok, here is some of the Visual Changes done to SW that was not included on the official list. Many are subtle but they are changes nevertheless. I'm sure I missed a few...
'77
'97 same font but thinner with wider spacing.
'04
'77
'81 different starfield
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'81 Aside from the different starfield and the new crawl, no thick matte line around the Stardestroyer.
'97 the original '77 starfield is back, the SW logo also recedes much faster into space than in the two earlier opening crawls.
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'97 digitally recomposited? or just cleaned up mattelines on the Blockade Runner.
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'97 recomp? motion blur on the pod & cleaned up matte lines on pod & ship.
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'97 I believe that all hologram shots in the film were recomposited in '97, they also removed the horizontal bars that was present on all original holograms...
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'97 ...and they forgot or didn't bother to reinsert the cone of light from R2 in two brief shots, the other is on the official list but it didn't include this one in Ben's hut.
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'04 CG clouds inserted to match the close-up of the suns.
'77
'97
'77
'97
I didn't bother to post the '97 digital landspeeder & Jabba the Hutt, I can post them if you need them.
Also this info is wrong:
The '97 version of this shot is exactly the same as the original besides the colortiming, it was in '04 they removed the landscape.