Technicolor - Dye Transfer Technicolor in Archival Work

Dye Transfer Technicolor in Archival Work

By the late 1990s, the dye transfer process still had its advantages in the film archival community. Because the dye transfer process used stable acid dyes, Technicolor prints are considered of archival quality. A Technicolor print from the dye transfer era will retain its original colors virtually unchanged for decades with proper storage, whereas prints printed on Eastmancolor stocks produced prior to 1983 may suffer color fading after exposure to ultraviolet light and hot, humid conditions as a result of less stable photochemical dyes. Fading on some prints is so rapid that in many cases, after as little as five to ten years, only the magenta record is perceivable on the film.

An article on the restoration of Star Wars Episode IV: A New Hope claimed that a rare dye-transfer print of the movie, made for director George Lucas at the British Technicolor lab during its initial run, had been used as a color reference for the restoration. The article claimed that conventional color prints of the movie had all degraded over the years to the extent that no two had the same color balance. However, because of the variation in color balance per print, dye-transfer prints are used in the professional restoration world as only a rough guideline.

Furthermore, three-strip camera negatives are all on silver-based black-and-white stock, which have stayed unaltered over the course of time with proper handling. This has become of importance in recent years with the large market for films transferred to video formats for home viewing. The best color quality control for video transfer by far is achieved by optically printing from Technicolor negatives, or by recombining the negative through digital means and printing, onto low-contrast stock.

One problem that has resulted from Technicolor negatives is the rate of shrinkage from one strip to another. Because three-Strip negatives are shot on three rolls, they are subject to different rates of shrinkage depending on storage conditions. Today, digital technology allows for a precise re-alignment of the negatives by resizing shrunken negatives digitally to correspond with the other negatives. The G, or Green, record is usually taken as the reference as it is the record with the highest resolution. It is also a record with the correct "wind" (emulsion position with respect to the camera's lens). Shrinkage and re-alignment (resizing) are non-issues with Successive Exposure (single-roll RGB) Technicolor camera negatives. This issue could have been eliminated, for three-strip titles, had the preservation elements (fine-grain positives) been Successive Exposure, but this would have required the preservation elements to be 3,000 feet or 6,000 feet whereas three-strip composited camera and preservation elements are 1,000 feet or 2,000 feet.

One issue that modern reproduction has had to contend with is that the contrast of the three film strips is not the same. This gives the effect on technicolor prints that (for example) fades cause the color balance of the image to change as the image is faded. Transfer to digital media has attempted to correct the differing color balances and is largely successful. However, a few odd artifacts remain such that saturated parts of the image may show a false color. Where the image of a flame is included in shot, it will rarely be of the expected orange/yellow color often being depicted as green.