There are many challenges in digitizing a media collection that spans 4 decades. Such was the case for Digital Revolution in digitizing Chevron’s vast media library.
Step one was for Chevron to choose which elements to preserve and which ones to simply degauss and recycle. Chevron historian John Harper thoughtfully made those decisions.
“The Chevron Corporate Archive partnered with Paul’s team at Digital Revolution based upon their professional expertise and proven ability in the field of media preservation. As a result, we were able to recover, preserve and utilize hundreds of media assets that otherwise we could no longer access or efficiently leverage,” Harper said.
The elements had come into the archives from all over the world. They included media from companies that Chevron had merged with: Texaco, Gulf Oil and CalTex. Digital Revolution spent three weeks on-site at the Chevron Archives, bar coding each asset and creating an inventory list of the chosen media.
The collection included fourteen different video tape formats, five audio tape formats, three film formats and 35mm slides. The videos included PAL tapes from overseas. They were digitized in their native format in order to maintain quality. We cleaned and scanned over 50,000 feet of film in high definition 2K resolution.
Digital Revolution recommended making two levels of files:
Video & Film: Pro Res 422 for the preservation archival format and H264’s for easy office use
Audio: .WAV files for the preservation archival format and MP3’s for easy office use
Conscious of the fact that the work we do today will still be used decades from now, Digital Revolution’s goal in preservation is to get the best quality playback possible. Oxide-based tapes: ¾” Umatic, 1” Reel, Betacam video and some audio reel tapes in particular gain moisture over time. Therefore, we “bake” those tapes to get the moisture out before playback. Otherwise, the tape can get stuck in the machine or the oxide can rip right off of the tape as it is played, causing “sticky shed.” As ¾” Umatic tapes decompose there can be a fine layer of oxide dust that forms on the length of the tape. As the tape plays in the machine it will cause a catastrophic playback head-clog. After baking the ¾” Umatic tapes, for many of them, we hand-cleaned the entire length of the tape with a moist alcohol cloth before playback.
We also had to perform tape repair and transplanted dozens of tapes into new shells. The most common tape repair happens when the glue that holds the recording part of the tape to the leader dries out and comes apart. The case needs to be disassembled and the tape spliced back together. In order for some tapes to track properly the tape itself needs to be transplanted into a new shell. Especially with ¾” Umatic and VHS tapes, the moving parts in the shell can dry out and cause the tape to not roll properly causing poor playback results.
Some of the Gulf Oil tapes had mold build up and rusty parts from being stored in a damp environment. When working with moldy tapes, Digital Revolution bakes them and then hand-cleans them. Then we transplant the tape into a new shell. All but one Gulf tape played back. It was too decomposed to salvage.
Most tapes have not been played in years. Therefore, they can tighten up or have sticking points. In order to loosen them up and get a more even playback we fast forward and rewind each one before digitizing. If a tape is so decomposed or damaged that we believe we will only get one good play from it, we capture it on first playback.
In working to get the best possible playback Digital Revolution has:
Machines with manual tracking, skew functions and adjustable audio output capabilities. We also have multiple machines of each tape format so if we are not getting good playback on one machine we can try others that may play a particular tape better.
As we digitized Chevron’s assets we also updated an Excel spreadsheet with metadata for each element.
When we were finished with phase one of digitizing Chevron’s media collection we had over 40 terabytes of data. We made two sets of hard drives and a set of LTO data tapes for long term archiving. When we were satisfied that we had a digital replica of the media collection, we degaussed and recycled the tapes.
For more information on how Digital Revolution can help with your media archive, contact me personally: Paul Grippaldi - firstname.lastname@example.org, 415-398-1200.