Paper presented by Ian J. Walker, Search Tech Pty Limited, at the 2nd National Preservation Office Conference: Multimedia Preservation - Capturing the Rainbow, in Brisbane, 28-30 November 1995.
- Search Tech Pty Limited
- Material Being Digitised
- The Benefits of Digitising
- The Numbers Being Used
- Equipment Being Used
- Retrieval and Indexing
- Use of the Images
- Preservation of Digital Images
- Quality Assurance
- Document Preparation
- Cost of Projects
- Funding Sources
Search Tech Pty Limited
Search Tech has been involved in the electronic preservation of photographic and artefact collections for the last eight years. During this time some of Australia's oldest pictorial collections have been electronically imaged for some of the largest public and specialist libraries and museums in the country. Many of the projects undertaken are now on public display. As well, flora, fauna and general Australiana have been imaged for photographers, tourism bodies, local councils, and state and federal government departments.
Material Being Digitised
Whilst the majority of material that has been imaged is photographic material, i.e., 35 mm, transparencies, prints, glass plates, film, etc., Search Tech has also imaged artworks, artefacts and objects. Using a video camera for the imaging means that there is no limitation to the type of material. It also provides the flexibility to capture a range of material sizes.
The Benefits of Digitising
The rationale behind many of our clients' imaging requirements is the preservation of material. Many of Australia's libraries and museums hold large pictorial collections of early Australian life and events. Many of the images are fragile and deteriorating and must be kept out of the light, and are therefore not accessible to the public at large. By imaging these collections a great many people are now able to view and have access to these collections that were previously not available.
Our recent clients have a variety of reasons behind their imaging requirements, ranging from greater staff and/or public access to material, better management of material, greater security, improved search access, less handling of originals, and increased revenue opportunities. Every client is unique as are their requirements.
The Numbers Being Used
To date Search Tech has imaged over half a million items. Approximately 500 images are captured per day, but the number varies greatly depending on the variety of material, for example, a collection of standard 35 mm slides as opposed to objects in all shapes and sizes. The majority of the images captured are on public display in Australia's major libraries and museums.
Equipment Being Used
Search Tech has continually kept abreast of the marketplace offerings in the area of imaging. We find that a broadcast quality video camera connected to a broadcast quality frame grabbing card, to be the most versatile means of image capture. Our camera is mounted so that the camera can be zoomed in to postage stamp size or zoomed out to A3 size without moving the camera; larger sizes are accommodated by repositioning the camera. The camera has electronic wiper blades to crop extraneous information from the sides of portraits or the top and bottom of landscape pictures; and an electronic positive or negative switch which means the operator is always looking at a positive image.
The capturing unit is set up with overhead lights and a light box; and on-line colour corrector which allows corrections to be made to compensate for different stock and the fading that occurs in colour negatives.
A major advantage of our system is the operator can always see, in real time on a large screen, the image that is being captured. Any imperfections, dust or hairs are readily noticed and can be removed and corrected instantly.
Another advantage is that the article being imaged is not damaged by the imaging equipment: no mechanical parts need touch the original.
Retrieval and Indexing
Search Tech introduced Perfect Pictures, the latest of our range of viewing software, to the marketplace early this year. Perfect Pictures is Windows compatible and based on QCOM's Corporate Retriever, a free text searching database. Free text searching is essential for a large diversified collection as you are not restricted to creating key words. The database allows you to have up to 50 user defined fields and up to 10 required field names, giving a total of 60 fields - all of variable length! Data can be keyed in a number of popular word processing packages, converted to ascii format and downloaded into the Perfect Pictures database.
Version 2 of Perfect Pictures is in the final stages of development. It includes many of the most asked for features from our clients, and will be released in December 1995. Perfect Pictures is one of the easiest and most user friendly viewing software programs currently available.
Use of the Images
The intended use of most of our clients' images is for research and reference purposes. Increasingly the system is being used by commercial clients where the images are used in publications and promotional materials. The resolution of the images is ideal for compository work but is generally unsuitable for high quality printing purposes. If the images are required at printing quality they would be scanned at medium resolution and high resolution at the same time, with the medium resolution images being used with the online system and the high resolution being stored separately on CDs. Images at high resolution would be provided on demand to clients.
Preservation of Digital Images
Once digitised the images can be readily retained for an indefinite number of years. There will be no loss in quality if the images are copied. If stored on an active file server the images will be regularly backed up and will be available as long as the file server is maintained.
The Images can also be backed up to magnetic tape or to CD-ROM. The CD-ROM format would provide the greatest level of security and longest life cycle.
Quality Assurance
As part of our process we undertake checks at as many places as practical. Images are checked at the time of capture with the operator seeing in real time on screen the image being captured.
Each batch of Images is checked at the end of each batch for consistency and correct numbering.
When descriptions are keyed and labels attached there is another check for correct matching and identification. Finally when the database is built there is a further check on the entire system.
Document Preparation
Preparation of the Documents-in this case images-is very important. The images can be in a variety of forms, including slides, transparencies, prints and glass plates.
Most clients take the opportunity to cull and sort the collection. The sorting and culling process can take considerable time and involve senior staff members, often the time and involvement is under estimated by clients.
Cleaning of the original material is generally undertaken if considered necessary and of course identification and numbering of each item if not already undertaken is essential. Finally after capture, or sometimes undertaken by the image capturers at the time of capturing, the collections are usually "bagged" or filed into archival secure wrapping materials.
Providing descriptions of each image is also of vital importance. The time taken in developing each Pictorial Description can far exceed the image capture time and often has to be undertaken by elderly people who can identify the material.
Cost of Projects
The cost of a project is best considered on a unit basis as the size of the collection is a major factor in determining the cost structure. Each image will cost approximately $A1.00 to scan in for a medium image and up to $A3.00 for a high resolution image. The image description can cost considerably more when staff costs are taken into account. $A2.00 to $A3.00 would be a general estimate but it could be slightly less if many images are indexed with similar terms. Also it could be considerably more if extensive descriptions are required.
Funding Sources
All the obvious sources of funding should be considered. Increasingly we are beginning to see projects become commercially viable when staff costs are taken into account and user pays principles are applied to outside clients.
Staff time can be greatly reduced as rapid access is provided to the collection. Search fees can be increased as they are more comprehensive despite staff time being greatly reduced. Revenue from prints, copies and usage royalties can increase significantly when the public are aware of the service that is available.
Cost of Equipment
Apart from the major cost of indexing and describing the collection the other cost is the bureau charges for scanning images which range from less than $A1.00 per image to up to $A3.00 per image.
The software - Perfect Pictures - costs $A950.00 for a single user and ranges through four users, eight users, sixteen users up to unlimited number of online users at $A5,000.00.
Alternatively image display software can be integrated to existing Library Management packages such as Dynix or Titan for a price depending on complexity but in the $A5,000.00 range.
Alternatively Search Tech can supply image capture units for clients own use for their collections. Prices range from $A25,000.00 for a low resolution system to $A40,000.00 for a high resolution.
Standard 486PC equipment is adequate as a viewing terminal and storage of the images can be undertaken on a file server. 15,000 images can fit on a one gigabyte hard drive. Costs of hard discs continue to fall and they are now around $A500.00 per gigabyte or 3 cents an image.
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