https://www.theasc.com/magazine/nov98/soupdujour/pg2.htm
A very cool read ....
Although mainstream audiences may not be consciously aware of the use of special processes when they watch a film in a theater, they certainly felt the effect while watching David Fincher's horrific thriller Seven (AC Oct. '95), which was photographed by Darius Khondji. A number of the film's release prints were treated with Deluxe's Color Contrast Enhancement (CCE) process to heighten the film's blacks and add a palpable texture and tonality.
Designed by vice president of technical services Beverly Wood and executive vice president of engineering Colin Mossman, CCE is one of three silver-retention processes offered at Deluxe. Shortly after the release of Seven, the laboratory introduced its Adjustable Contrast Enhancement (ACE) process, which shares many of the same features of CCE, but is also scalable, like its Technicolor cousin, ENR. "I can tell you that ENR and ACE are similar processes," Wood submits. "In fact, Alien: Resurrection [AC Nov. '97] had its dailies and answer print done by Technicolor, but the release prints were done by Deluxe because of a contractual situation with the studio. The director, Jean-Pierre Jeunet, compared our ACE check-print with his ENR answer print and was quite happy with the result. And with the recent advancements in both our chemical and mechanical technology, we were able to meet the film's large print demand on time.
"CCE, however, is something very different from ACE," she notes. "CCE is a proprietary process that produces a much higher contrast and adds more grain. When you have more silver, you have a more grainy look and blacker blacks. However, your blacks can also plug up more. With a bleach-bypass, the tones are much duller and more muted, and you have a lot less detail in the shadows. The blacks are very black, but the nuances in the gray are diminished. We do get some clients who want that look, but most of the time people say, 'I want the blacks to be black, but I still want some shadow detail.' This is why they are usually more interested in [silver-retention] processes such as CCE, ACE or ENR.
"These tools are nothing in hands of those who are not sure of what they're doing," she adds. "I've had a lot of people come in and consider using silver retention as an afterthought. They'll say, 'Take my negative and give me a CCE print because I want the look of Seven.' We will do the print for them of course, but when they say, "It doesn't look the same!' it is because the look of a film is truly a collaborative effort between the director, the cinematographer, the gaffer, the production designer and the costumer. The choices that are made in the art direction, the colors and the lighting really do make a difference. Now, I am by no means an expert on all of the things that the true experts do in order to create a certain look, but I know from working with cinematographers that it's important to shoot tests and actually go through the IP, IN and release-print stages to be sure about the look that they want."
Just as Technicolor controls their ENR process, Deluxe monitors the levels of silver retained by CCE and ACE at 1000nm. Wood notes that when Deluxe monitors the D-max reading on a normally processed 21-step wedge, the print yields an IR number between 58 and 60. "When you skip the bleach completely on a piece of print film and retain 100 percent of the silver in the film," she distinguishes, "that IR number goes up to 240 — effectively four times as much silver in the film than there should be.
"When you keep 100 percent of the silver in, the blacks look great in the dark parts of the room, but the faces now also have a lot of silver in them as well, so their contrast is all messed up. The fleshtones may look old and hard; therefore, you may say, "Can I back off on the amount silver in my print and still keep some of the normal nuances of the curve?' What this basically means is that you should try to make only the top part of the curve increase, while you keep the toe area the same. To do that, we back off from skip bleach and go to CCE. When we set up our proprietary set of events in terms of printing and processing, we end up with a D-max IR reading of 180 to 190. We now have about 75 percent silver in the print. What you will then see on the screen is that you now have some nice desaturation in the color; there's still a little bit of grittiness and grain to it, but you'll have more detail in the blacks than if you just skipped the bleach. For a movie like Seven, where the lighting was predominately on the upper part of the curve because the whole movie was so dark, going with CCE was one of the reasons that film looked so good.
"[Director] John Frankenheimer fell in love with the CCE process with the few prints we did for him on George Wallace," she adds. "Now, he just released Ronin with a select number of CCE show prints, while the majority of the release had normal prints. But since Robert Fraisse [AFC] did a fantastic job on the photography, providing a solid, rich negative, you may not notice the difference unless you distinctly know the look of CCE and compare the two types of prints side by side."
Finally, in the hierarchy of silver-retention techniques available at Deluxe, the lab offers its ACE process. "When we're presented with films like Alien: Resurrection or The X-Files — where the filmmakers want deep blacks, but still want the colors to look true and have a good level of chroma and texture in the mid-scale regions — we'll back off from CCE and give them ACE," Wood explains. "With ACE, we can give them 30, 40 or 60 percent, or whatever level they want. We can make those specific nuances by making chemical changes in the process. We did about 3,000 prints for both Alien: Resurrection and The X-Files, and both were released with about a 50 percent level of ACE."