Comparison between the 4K Blu-ray (identical worldwide and presumably soon to be common on streaming providers with UHD option) and the Blu-ray version (first released in 2012, only repacks were re-released in the new set in 2021 as well).
Indiana Jones and digital changes to re-releases for classics
In May 2020, we were able to report that Star Wars had received digital adjustments for its 4K premiere. Undoubtedly, this series in particular has already been notorious for always making new changes with another medium since the laserdisc, and George Lucas is a favorite bogeyman among many a purist-minded fan. But over the years, other directing legends have also liked to make subtle changes to their classics: Sam Raimi, for example, covered-up several goofs in Evil Dead. Another example would be James Cameron. He made various retouchings in Terminator 2 for the 4K/3D release and also extensively reworked Titanic.
Indiana Jones was Harrison Ford's second really big franchise lead role after Han Solo. Here, too, George Lucas had a say as producer and left the direction to the then up-and-coming Steven Spielberg. Spielberg, in turn, is no stranger to subsequent improvements of his classics with modern computer technology. His special edition of E.T., in which the military suddenly waved around with walkietalkies instead of weapons, is unforgotten. And that brings us to the crux of the matter: In all three parts of the Indy "original trilogy", various (mini-)corrections can now be found in the picture material in the 4K UHD premiere, which has been available since June 10, 2021.
For the most part, we can summarize that this is due to the higher resolution on the one hand, which now makes small details visible that were previously barely noticeable for short moments or only comparatively small in the background. On the other hand, various optical effects and transitions to matte paintings have been slightly polished up with modern technology. The films are otherwise still frame-exactly identical and most of these changes can definitely be classified as positive. Nonetheless, they are after-the-fact edits.
The adaptations for part 1 - Raiders of the Lost Ark
For the present first part, Raiders of the Lost Ark, one can first note that several minor film flaws have already been touched up in all digital releases since the 2003 DVD premiere. The most famous is the reflection of the snake in the glass in front of Indy, but also retouched wire ropes or other typical aids of analog special effects were addressed here. So the film has always been a "burned" child as far as changes to the original Theatrical Version are concerned - even though the interventions were by no means as extensive and interfered with the plot itself as in E.T. or Star Wars.
What caused an uproar in advance in forums, such as the thread on Blu-ray.com, which already counted 250 pages on the release date, were screenshots of individual scenes and finally at Caps-a-holic. Especially the scene of the nighttime digging at the "Well of Souls" stood out, as several characters were suddenly slightly distorted in this frame-by-frame shot. Here it became apparent that this effects shot had been digitally remounted. An uncritical revision in itself, but reason enough to take a closer look at the rest of the film in direct comparison.
It was also much discussed that in the finale, the lamp on the pole to which Indy and Marion are tied now looks uniform. This was probably done partly for continuity reasons, though ultimately inconsistently implemented. Beyond that, what stands out most, as mentioned above as a summary for all three parts, are reworked transitions of matte paintings and visual elements. We can basically state that the changes might not have been necessary, but they don't really harm the film either. And qualitatively, the new 4K Blu-ray is clearly superior to the previous Blu-ray, so we can give it a clear recommendation to buy.
Finally, two disclaimers:
1) Both the referenced image comparisons and especially our screenshots, which are heavily compressed in size, should be taken with a grain of salt when it comes to a quality verdict. On the one hand, the detail gain is only visible on good UHD equipment. On the other hand, these are HDR->SDR converted images. The additional color space results in a different picture when played back on the TV in HDR, so that the SDR screenshots, which tend to be a bit darker, only show "half the truth".
2) Of course, we compared the complete film specifically with the new 4K set, which also includes Blu-ray repacks of the old discs in Germany. At this point, however, special thanks go to the users in the Blu-ray.com forum, by whom many of the mentioned differences were noticed for the first time and were analyzed in more detail. Due to the deliberately rather inconspicuous nature of such changes, we would also like to give no guarantee here that all digital changes were found and listed in the report.
The lettering "South America 1936" can be seen a bit longer in the 4K version: This now goes all the way to the end of the shot, while the old version faded out just under 2sec before.
Strange: The somewhat blurred shot from behind in the cave was apparently digitally recreated in several places.
Especially with these small comparison pictures, however, this is unfortunately absolutely not noticeable for this first image change. We have therefore also stored the entire screenshots in 1080p:
Fullscreen comparison on Screenshotcomparison.com - Part 1 and Part 2
A curious moment from the Blu-ray master that was presumably not present in this way in previous releases of the film has been undone. The eyes of Satipo (Alfred Molina) have been morphed a bit larger here for a brief moment, so that they protrude from the side, creating a small dent on his face as well. Since he sees the spiders on Indy's back here, this should possibly bring out his shock a bit better. In any case, in UHD you can now see the original shot again. A slightly different shape of his shirt is also noticeable here in detail.
As with the following differences: First the normal image, then zooms in on relevant parts.
The plane is now more cleanly blended into the environment. On the Blu-ray, you could see the gray edge from being copied in, especially at the top. Also, shading has been added in various places on the water to make it look a bit more realistic.
When Indy and the others are digging around at the "Well of Souls" at night, the background and actors have been recomposed.
One of the things that is noticeable when you look closely is that...
a) Sallah and Indy are now a bit thicker - though the 4K version is more realistic
b) The end of the shovel held up slightly to the right in the picture is also different
c) The rocky outcrop on the right of the image also moves a bit further to the side in 4K
For better zoom comparisons for this shot, in addition to the previous link on Screenshotcomparison, you can refer to the full-frame comparison of Caps-a-holic.
A mini goof was corrected here: The flash was visible for a short moment not only in the background, but also partly above Indy's hat. This is now no longer the case.
By the way, you can also see here that Indy's stature has changed slightly when you superimpose the images directly. In 4K, he is a tad wider.
Again, the Well of Souls. As a proxy, please refer to a post in the Blu-ray.com thread that points out, based on two frames in direct succession from exactly this spot, that around Indy and Sallah in particular, smudges were also made unrecognizable with a blur effect here.
Ditto Well of Souls.
And one more time.
Note: Right after this comes the infamous shot where you originally saw the reflection of the snake on the plexiglass between it and Indy. Already since the first DVD edition, this film flaw has been digitally fixed and in principle nothing has changed in 4K.
Only in the large direct comparison, however, it is visible that in this shot again some dirt around the snake was made unrecognizable with a blur effect. Oddly enough, Indy's jacket has thus also acquired a slightly different shape.
A matter of taste to what extent one wants to see this as a change: the Blu-ray in particular often had teal effects, i.e. a look that veers heavily into yellowish/orange. This quasi-modernization is often viewed very critically by purists. In the present timecode, the golden chest is lifted. In an extensive post on the Blu-ray.com forum here, starting with a 1981 theatrical print, it was collected how this scene has changed in color over the years. While on Blu-ray Sallah and Indy also look similarly golden to the chest, this has at least been toned back a bit in 4K - although the older versions here looked more noticeably different.
Note: At 85:39-85:43, the jeep is seen plummeting down the canyon, with a relatively obvious matte painting also being used. For an HDTV release, this was cheaply re-backgrounded (comparison video on YouTube) in the years leading up to the Blu-ray premiere. After some fan complaints, however, the original background was back on the Blu-ray. So this was just an interim TV curiosity that was fortunately not preserved on any digital medium. Also with the 4K-Blu-ray they refrained from changing that again.
The light on the pole has been reworked. This can be interpreted as useful at this point, because the lamp now looks the same as other lamps in shots before and after this scene.
In addition, you could also clearly see the copied-in edge around Indy and Marion in this shot earlier, which is no longer the case.
After all the lamps have burst and the ghosts have been freed, the light here diverges again. Why it suddenly shines brightly again in the 4K version now, even though it failed shortly before, can't really be explained in any meaningful way, though.
A somewhat sloppily implemented visual effect has been corrected: Previously, a thick black edge could be seen under the soldier's right arm and especially his hand from being copied in.
As the lid of the Ark of the Covenant comes back down, you will again find, especially on the left of the image, a relatively striking example of a matte painting that is now more cleanly incorporated.