The process of my "review" has to include a bit of school house on motion picture tech from the photo-chemical era. I hope you will not only endure it, but enjoy it.
The first thing I have to do with you is explain why the 70mm print is the reference. Of course we have to start with the fact that the movie is shot in 35mm anamorphic, with which lenses, which negative stock, their properties, how the director of photography shot the movie, how the 35mm version gets blown up to 70mm, and that most 70mm theaters were flagships of the day. I’ll try to condense these facts as much as possible.
In 1979 (when ESB was shot) there were really only two format alternatives that were appropriate for the scale of the story: 35mm anamorphic or 65mm Super Panavision (spherical). Although desirable on many levels (even today), 65mm was too expensive to shoot on the ESB budget (that ballooned to $18M). Well-shot 35mm anamorphic still provided a large, bright frame that was a solid foundation for 35mm release, but also a great product for 70mm blow-up/print-up. Here is an excellent article on the “print-up” process of Panavision 35 to 70mm. You will see that it was a collaborative effort between Panavision, Eastman Kodak, and the film labs, as each plays an important role. http://www.widescreenmuseum.com/widescreen/35-70mm.htm
ESB was shot with the Panavision C-Series lenses. A number of the feature films on which I worked were anamorphic, and the smaller C-Series along the larger E-Series were the workhorses on all of them...and they are used extensively to this day. Here is a rundown of movies shot with them. It’s a boat load. https://shotonwhat.com/lenses/panavi...ies-anamorphic
The ESB negative (camera) stock was Eastman 5247, the state of the art stock for many years. 5247 (ASA 100 tungsten balanced) was very fine-grained with wide exposure latitude and great color and contrast. The director of photography, Peter Suschitzky, lit and exposed ESB so as to deliver a balanced image, despite elements of some scenes pushing the extremes of the latitude of the 5247. The scenes on the carbon freeze set are good examples of very high contrast that still are comfortably within the latitude of the stock.
The C-Series 30mm to 100mm lenses were on ESB. Not all of them are razor sharp, but all render good resolution in the centroid ellipse almost edge to edge, and have very good contrast. The C-Series lenses are reasonably fast, but…very unforgiving below about T2.5. Therefore it is highly likely that ESB interiors were shot around T4 for 24 FPS non-effects shots. Imagine how much power and lighting hardware was necessary to render a T4 exposure at 100 ASA! That means that there was over four times as much light on those sets as is necessary for the contemporary Kodak stocks of today at ASA 500 tungsten. To deliver high resolutions shots, the focus puller needed to be on his game. He was most of the time, but there is the occasional miss in the movie.
Next up is interpreting film images, based on the “gamma” that is “baked into” the chemical emulsion, and why that is important to the interpretation/review of BD/video images. Cheers.