ITU-R BR 1219-1995 Handling and Storage of Cinematographic Film Recording《电影胶片记录的处理和保存》.pdf

1、Rec. ITU-R BR.1219 1RECOMMENDATION ITU-R BR.1219*HANDLING AND STORAGE OF CINEMATOGRAPHICFILM RECORDING(Question ITU-R 109/11)(1995)Rec. ITU-R BR.1219The ITU Radiocommunication Assembly,consideringa) that programme production for international exchange release is largely based on film;b) that program

2、mes stored on 35 mm cinematographic film provide a high-quality source input required withfuture conventional 16:9 television and HDTV services;c) that such programmes are archived for a very long period of time;d) that during archival storage such films may be reused many times for the transfer of

3、the programme from filmonto tape;e) that loss of technical quality during the lifetime of the archived programme must be avoided;f) that proper care when handling the film before, during and after each archival interval is a pre-requisite for thesuccessful retrieval of the programme;g) that the vine

4、gar syndrome affecting the film base may require special attention in this respect,recommends1 that the handling and archival storage of programmes on cinematographic film should be carried out followingthe guidelines given in Annex 1.NOTE 1 A glossary of special terms offering a more detailed analy

5、sis concerning this subject can be found in Annex 2.ANNEX 1Handling and storage of cinematographic film1 Handling of cinematographic film The manufacturers recommendations for processing and drying should be carefully followed. The film must be properly washed and stabilized to prevent stains, dye f

6、ading etc. Cleanliness is essential. The incoming air should therefore be adequately filtered. Smoking, eating or drinkingshould not be permitted during film handling (see Note 1). Films should be handled carefully by the edges using thin cotton gloves. Cleaning operations should be applied gently a

7、nd solvents should be checked for purity and stabilization prior touse. Film should be kept either in tinned/polyethylene coated metal cans or in plastic cans (see Note 2). Rusty cans mustbe replaced immediately. Film should not be wound under extreme tension. Film intended for long-term archival st

8、orage should not contain mechanical joins (see Note 3)._*This Recommendation should be brought to the attention of the Telecommunication Development Sector (ITU-D).2 Rec. ITU-R BR.1219NOTE 1 Gelatine emulsion layers are sensitive to physical scratches. Dust and dirt particles tend to adhere to the f

9、ilmsurface and can cause film wear.NOTE 2 Preferred materials for plastic containers are polyethylene and polyolefins (polypropylene).NOTE 3 It is recommended to make an interpositive of the film intended for long-term storage. If splices cannot beavoided, conventional cement joins should be made. T

10、ape splices should not be used. After some period of time joinscan stretch apart when film is rewound and adhesive can ooze out and migrate to adjacent turns, causing winding andreplay problems.2 Storage of cinematographic film (see Note 1) Cleanliness is absolutely necessary. The incoming air must

11、be filtered and should develop a positive pressure in thestorage area. Temperature and humidity should be kept as stable as possible (see Note 2), and preferably below those in theoperating environment. Suitable values are in the range:for medium-term storage with immediate access to programmes (see

12、 Note 3): temperature: 15 C maximum relative humidity: 30-40%for long-term storage for archival preservation of valuable films (see Note 3): temperature: 2 C or lower relative humidity: 25-30% Film should be stored either in tinned/polyethylene coated metal cans or in plastic cans. Rusty cans must b

13、ereplaced immediately. The cans should be stored horizontally to prevent crushing of the film. Films and containers should be inspected at regular intervals. Storage rooms should be protected against fire, flooding and industrial fumes.NOTE 1 The base of triacetate films and magnetic tapes can be af

14、fected by the “vinegar syndrome” and thereforerequire strict observation of the recommendations given above. The typical indication for the syndrome is the smell ofvinegar.For triacetate based films that appear to be affected by the vinegar syndrome, the following procedure is recommended: Isolate a

15、ny films and tapes that show signs of degradation and store them away from unaffected materials. Do not store films affected by the vinegar syndrome in rusty metal containers or in air-tight bags. Avoid contact between film or tape and certain types of paper or plastic material. Use acid free paper.

16、 Check the suspected films and tapes at regular intervals (2-3 years) to determine whether they show signs ofadvanced degradation. Preserve the programme content of affected films or tapes for future use by copying onto polyester based films andmagnetic tapes. Affected programmes could also be trans

17、ferred to videotapes.NOTE 2 Condensation should be avoided: Care should be taken to avoid temperature and humidity variations duringstorage and handling.NOTE 3 These climate conditions correspond to European Broadcasting Union (EBU) Recommendations prepared bySub-group G3, taking into account the sp

18、ecific storage requirements of broadcast organizations to access archived film atshort notice. They therefore differ in some parts from the conditions given in the Society of Motion Picture andTelevision Engineers (SMPTE) Recommended Practice RP 131 and in ISO 5466.Rec. ITU-R BR.1219 33 Splicing of

19、film productions for long-term storageFilm splices are either made using cement or tape. The cement splice is the industry standard method for negativehandling and storage, while the tape splice is only suitable for editing and should never be used on material forlaboratory, telecine or archival pur

20、poses. The characteristics and properties of cement and tape splices are very welldescribed in the paper “Film Splices” by Harold Brown, FIAF Preservation Commission.3.1 Cement splicesThese splices are generally reliable, even after many years storage, however, they can deteriorate for the following

21、reasons: human error, i.e. the splice was incorrectly made, e.g. the emulsion layer not removed correctly, the film cement used was of poor quality, the film splicing machine was incorrectly adjusted, the splice has suffered “wear and tear” damage due to mishandling, the cement has deteriorated due

22、to the action of solvents.The experience of broadcasters, together with the film laboratories, is that conventional cement splices rarely giveproblems provided that the splices are properly made and inspected before any operations such as printing or telecinetransfer. The usual problem is that splic

23、es “dry out” causing them to separate. This occurs if the splice was not madecorrectly in the first place. If a splice does fail during printing, it rarely causes damage to the negative and can normallybe remade.The one unknown factor at the moment is the long-term effects of the increased use of so

24、lvents in wet-gate printing. It isthought that, if the splice is correctly made, then there should be no problems. However, there is growing evidence thatsplices can be weakened by solvent action, but only if the splice was not perfect in the first place. A cementsplicer (Hamman) is now available wh

25、ich produces “butt” cement splices without the increased thickness as for aconventional splice. As this is a recent development, there is as yet little experience of how well these splices survive.3.2 Tape splicesTape splices are made with a clear adhesive tape, and provide a quick and convenient me

26、thod of joining film, which isespecially suitable for editing. However, problems will occur if a film with tape splices is stored for any length of time.These problems relate to the properties of the adhesive used on the joining tape and include: joins can stretch apart when the film is wound in rol

27、ls, adhesive can ooze and may stick to adjacent turns causing winding problems, after a long period of storage, adhesive can ooze from the edge of the tape joins to form a layer between the edge ofthe film and the film can.Stretching normally happens slowly, over a period of weeks or months, but if

28、the film is wound too tightly or stored attoo high a temperature, it can happen in a matter of days. If a film with stretched splices is run on a machine then it maybe damaged. An affected film may need to be cleaned with an approved solvent to remove any traces of the adhesive.The old tape joins sh

29、ould be removed and replaced.If this oozed adhesive is still soft, the film can be treated with an approved solvent so that it can be unwound. The oldtape joins should be removed and replaced.In some cases, however, the layer may have hardened and solvent treatment may not be possible. This means th

30、e film isnot recoverable.In view of the above problems, tape joins should not be used for material which will be stored for long periods, andespecially on archive material which may need to be reused.4 Rec. ITU-R BR.1219If any archive material is known to have been joined with tape splices, then the

31、 splices should be remade and the filmshould be copied by making: a master positive on intermediate film if the film was a negative, a reversal copy if the film was a reversal master, a videotape copy of either.3.3 The current situationOver many years, the film industry has produced a large number o

32、f different 35 mm mechanical splicing machines whichare more or less demanding on the skill of the operator for good results.For 16 mm, the situation is different because there is not sufficient area between film frames to make a solid, durablesplice that is invisible, as can be done with 35 mm film

33、. Therefore, the chequerboard A/B roll method of negativeassembling was developed to get round the problem and it is now the established method for cutting 16 mm negative formaking prints.However, if a chequerboard negative is run on a telecine for video transfer, there will be picture unsteadiness

34、at thescene changes since the increased thickness at the splices creates unwanted movement. Therefore, the A/B rollsassembled for telecine transfer have to have the scenes extended at the beginning and end. The cut to black is madeelectronically. This can be a problem if both video transfers and fil

35、m prints have to be made from the same negativebecause overlaps are present in the cut negative which cannot be used on a film printer.Many broadcasters have established production methods where the programme is shot on film and the processednegative is transferred to video on telecine. Post product

36、ion takes place wholly on video. If it is decided to preserve thisprogramme on film, the question arises how should the negative be assembled for future use? There are three mainpossibilities:Option 1 : make a traditional chequerboard negative for printing.Option 2 : make an A/B roll negative with p

37、icture overlaps for telecine transfer.Option 3 : assemble the selected takes as a “rough cut” single negative roll so that the programme can bere-assembled at some future time. A computer logging system will have to be used at the telecine transfer stage so thatan edit decision list, EDL, and negati

38、ve cutting list can subsequently be made.Option 1 results in a conventional chequerboard cut negative and prints for projection or telecine transfer. Further printscan be produced later on but the negatives will not be able to be transferred to video without picture instability at thesplices. This i

39、s the most expensive solution, but the most flexible.Option 2 results in two rolls of negative that can be re-transferred using an A/B auto assembly process from telecine totape. If a print is required then the negative will need to be re-cut to a normal printing chequerboard.Option 3 is the least e

40、xpensive way of archiving the programme. The programme can be reassembled using theEDL lists. All the “out takes” of the negative originals can be discarded and the rough cut negative can be re-transferredon a telecine without a wet-gate because it will not suffer from dust and dirt near the splices

41、. This option will also givethe possibility to re-cut the negative to make a chequerboard negative for printing.3.4 The futureThe conventional cement splice is still the best way to join acetate film for production and storage. The introduction ofpolyester film base would be good because of its bett

42、er storage properties but producing a splicing system that isinvisible is a challenge for the commercial industry. For the broadcaster, there are several options when using film as therecording medium. The ideal is to provide a film for archiving with no joins as can be done by making an interpositi

43、ve.However, this is very costly. The most practical way is to choose one of the options above which use conventionalcement joins and to ensure that the joins are correctly made. Which option is chosen will probably depend upon thefunds available for the production.Rec. ITU-R BR.1219 5ANNEX 2Glossary

44、 of special termsDye fading of print filmsThe change in colour-balance resulting from a density loss of 0.1 in one or two of the three layers at a density of 1.0 isjust perceptible, especially under television viewing conditions.The change in a regraded image after a density loss of 0.2 may be perce

45、ptible to a trained eye, but is normally notnoticeable to the average viewer.The net result of a density loss of 0.4 is definitely noticeable and is generally considered unacceptable.Short-term storageFor films in post-production, distribution, broadcasting, etc., storage should preferably be below

46、room temperature withcontrolled relative humidity and clean surroundings.Medium-term storageStorage time up to about ten years.Films still accessible within short notice. Temperature certainly below room temperature and also controlled humidity.Long-term storageStorage of up to about one hundred years.Films are no longer accessible on short notice. Strictly controlled temperature and humidity.Archival storage conditionsArchival storage conditions are those which are suitable for the preservation of films having permanent value, e.g. morethan one hundred years._