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published: March 2004
A Whale of a Web-site
Anne Karin Hufthammer, Natural History Museum, Bergen and Joan C. Nordbotten, University of Bergen, Norway
The Natural History Museum at the University of Bergen has a unique collection of 24 whale skeletons on display that is believed to be the largest of its kind in the world. The museum wishes to make this collection, which literally fills 2 rooms, accessible to the international community through a Web exhibit. Our principle challenges include a limited budget, selection of appropriate filming techniques, and content presentation to a varied public that includes both researchers and school children. Our goal is to provide an exhibit that can support both the in-depth and broad overview interests of our anticipated users.
The whale skeletons in our collection are large objects up to 24m (80ft). We are therefore exploring alternatives for inclusion of video presentations in the exhibit design. One option is to use an overview video and develop a two-level interface in which images, video, and audio clips of the whales with maps and stories are linked at the surface level where we expect the general public will browse, while research data that supports study of skeletal material is linked at a deeper, zoom level. An alternative is to use an architectural sketch of the physical exhibit as the interface and focus on development of item videos for presentation of the individual skeletons of each species.
In this paper, we present an evaluation of alternative uses of video and zoom technology for exhibits of large-scale objects. We demonstrate that adequate video quality can be within the economic reach of low-budget museums.
Keywords: Web-Exhibits, Web design for large-scale objects, video applications, whale exhibits.
The Whale exhibit
Since the late nineteenth Century, whale skeletons have been the dominant zoological objects in the exhibitions of the Natural History Museum at the University of Bergen. In two halls, of more than 300 m2 (3267 ft2), 22 complete skeletons and 2 crania, representing 18 whale species are permanently exhibited. When a new exhibit of the Greenland whale opens, primo 2003, the whale exhibit will contain all of the North Atlantic species.
The exhibition was mounted over a period of approximately 30 years and was completed in the 1920s. At that time it was regarded as one of Europe s best exhibitions. During most of the 20th century, the Hall of the Whales was kept undisturbed and after some years it got a neglected and somewhat dusty appearance. This neglect has probably, in some sense, saved the collection, as a renewal would most likely have resulted in a demounting of most of the skeletons.
The largest skeleton in the collection is that of a 24 metre (80ft) long blue whale and ten of the skeletons are more than 6 meters (24ft) long. The skeletons hang close together, the tails of some under the head or within the ribs of another. When looking into the Hall of the Whales one might get the impression of a room filled with large hanging bones in which it is difficult to separate one skeleton from the other.
Systematically whales can be separated in baleen and toothed whales. From a pedagogical point of view, it would be an advantage if the whales were exhibited according to their zoological system, i.e. the toothed whales separated from the baleen whales. However, in this exhibit toothed and baleen whales hang side by side, reflecting the fact that literally each whale was mounted in the exhibition as it was acquired. In fact it seems that the exhibition was regarded complete when the rooms were packed.
A museum has obligations to the general public, including small children, school children and adults as well as to the scientific community of students and researchers. These groups have very different requirements as to how the exhibition should be presented. A child might look for huge animals, an artist for strange and beautiful structures, while a scientist probably would like to look into scientific features, to study morphological and systematic questions.
Scientific zoological collections are normally not on public display rather they are stored and made available to scientists and students only by request. However, the whale skeleton collection is on display in addition to being part of the scientific collection of the Zoology section at the natural history museum in Bergen. In general, small to medium sized skeletons can be borrowed and are sent to research institutions all over the world. However, both the display status and size of the whale skeletons make it impossible (impractical) to disassemble and send a whale skeleton to an interested researcher.
Today the collection is believed to be the largest of its kind in the world, offering researchers, students, and the general public a unique opportunity for morphological, molecular, and general study of whales. The study of whales requires a high degree of international cooperation, since both skeletons and live animals are relatively few and spread throughout the world. This collection lies in a small city, geographically far from other marine study centers and museums.
Since travel is expensive and the exchange of whale skeletons is not practical, the museum is exploring possibilities of using the Internet as a tool to present the collection to an international audience, support research, advertise the collection and hopefully to substitute for some of the current travel to the sites of the skeletons.
Design framework for the Virtual Whale Exhibit
The basic objective for the virtual exhibit is to present the historic exhibit and provide both pedagogic and research presentations of the individual whales in the collection to a wide audience that includes researchers, students, and the general public.
Filming the whale collection for Web presentation is a challenge, due to the size of the skeletons and the physical layout of the whale collection, which includes overlapping skeletons and shares space with specimens of seals, fish and marine invertebrates. As shown in Figure 1, only part of the exhibit and/or part the larger skeletons can be captured in one image. In the center-left of this image, we see the head and ribs of the 24m (80ft) blue whale, while on the right we can see the ribs and fins of a 18.5m (62ft) Fin whale followed by the tail of a 13.5m (45ft) Humpback whale. Therefore, some form for video will be necessary for presentation of the largest skeletons.
Figure 1: The Whale Hall at the Natural History Museum in Bergen
Anticipated users for a whale exhibit
We anticipate that the user groups will have overlapping, but distinct usage profiles.
Researchers (including university students) may be interested in various aspects of the physical exhibit, particularly its contents, but are expected to be primarily interested in examining the skeletal material and its documentation for support in their work on identification and classification of their own material.
Students (grades 1-12) are expected to be interested in general descriptive information size, speed, food, range, and special characteristics of a specific (set of) species. Assuming that they are working on projects, it will be necessary to give them sufficient material for comparison among species.
Causal or general public users are expected to use the site for answering specific questions that have arisen during a conversion or when reading material related to whales. For example, which are the longest whales (implying identification of the longest whale species) or what is the population of the most numerous whale species? These questions will commonly require calculation and comparison of the underlying data in the system.
In addition artists, in particular sculptors and painters, frequently visit the physical exhibition for inspiration. For this group, the web presentation can advertise the existence of the hall and be an invitation to visit.
Table 1 outlines Web-usage characteristics expected for the users. One can also anticipate that the attention spans for the different users will vary from hours to seconds depending on the information need. General public users can be expected to have a significantly shorter attention span the either the research or educational users (Nordbotten, 2000).
Table 1 Exhibit users
The central item for the whale exhibit is the skeletal collection. As noted above, the physical layout of the whale collection, as well as the size of the individual skeletons makes filming the collection difficult. Ideally, the skeletons should be presented as 3D objects that can be rotated so that various perspectives could be presented. Given the current resources, the layout of the physical exhibit, and the capacity of scanning equipment, this is not a viable option. Since it is not possible to capture the large skeletons in a single image or construct 3D images of them, some form for video representation is required.
In addition to the skeleton collection, there is a varied collection of data about the species in the whale collection, including video and audio clips of live animals, drawings and images, text documents, as well as research data detailing both the species and the skeleton collection. Table 2 presents the data to be included in the site and gives the current status of its collection. The data are being stored in separate Oracle 9i databases to allow maximum flexibility for the site design.
Table 2 Exhibit content
A Web-site, by definition, can only be viewed/used by persons who have Internet access and have sufficient technical equipment to display the data presentations included in the site text, images, animation, sound and video, in order of technical support requirements. In a recent survey, Global Reach (2002) estimated that 10% of the worlds population, or 640 million people, have Internet access. Of these, 37% are native English speakers, 36% speak one (or more) of the European languages, and 28% speak one of the Asian languages.
Table 3 gives relevant characteristics for 3 technology levels that can be used to view Web exhibits containing image material. A minimum operative environment is Windows 98 or an equivalent with a graphic card. High-end machines are required for good video presentation due to frame sequence timing and large data volume. Note that column 5 gives the maximum download capacity per minute, which can be calculated as the connection speed * 8bits/byte * 60 sec. Actual download time will be less and vary according to the current network traffic.
Table 3 Technology requirements for viewing image material
ISP-Planet (2002) reports that In-Stat/MDR analysts estimated that there will be 46 million broadband subscribers by the end of 2002. If we assume that many subscribers are businesses or public organizations, we can estimate that about 10-15% of the estimated Internet users will have broadband access. That translates to about 80 million persons (about 3% of the world population) who have access to the technical capability to view video with reasonable quality.
The anticipated users of our site represent a very broad scope of Web users and must be expected to have a wide range of technical equipment from basic to high-end systems. If we assume that the mid-level technology required for presentation of video content may not be available to all anticipated users, than our site should provide ample supplemental material for the video components.
Using Video for Presentation of Large Objects
The physical size of the whale skeletons indicates that some use of video presentation will be important. Video and audio material of live whales is also part of the collection, in addition to more standard document and image materials. The goal is to present this material in such a way that most of the desired users will be able to gain maximal information from the exhibit.
Video s place in Web exhibits
Video is a relatively new element in Web exhibits, not least because it can be expensive to produce and requires that users have high-end equipment for good viewing. Currently, video has been used mainly for virtual tours of the physical museum and/or special exhibits. We can identify 3 different video types that can be employed in an exhibit:
1. The overview video, or film, can be used as an introduction to the physical museum. These videos frequently provide a rotational view of a room that can be stopped at an interesting item and the zoomed to get a closer / enlarged image of the object. Links can be inserted to support passage to another room (another video sequence) with the same rotational presentation. Links can also be added to switch to a more detailed presentation of the selected item. The trade offs here are between download time and zoomed image quality. Good quality zoomed images require high-density images.
Examples of uses of overview videos can be found at:
2. Topic videos, including animation, can be used to tell a story. Typically, the viewer can view the video and interact with it, but cannot query for information outside of its scope, for example from the underlying museum collections. Exhibit videos of this type have been used for:
3. Item videos can be used as exhibit items to show detail in a stationary or motion item such as a statue or dance respectively. These videos can be linked to the overview video, or collected as exhibit items. Examples can be found in the video collection in the Bhutan Fortress of the Gods at www.bhutan.at / the objects / Vienna exhibition / Video. Here video objects are presented as a collage.
The video type chosen for an exhibit needs to match the anticipated use of the exhibit. Table 4 presents a mapping between video types and the users information requirements shown in Table 1 above.
Table 4 User requirements / video type
Using video for the exhibit overview
Given the size of the whale skeletons, it is tempting to consider use of an overview video for the exhibit map. Since one implementation of zoomed images is actually a switch to another image at greater detail, links can be hooked at various image depths, thus providing support for both broad and deep interest levels in the user population.
Our initial video set was made by professional photographers who used 360 rotational (VR) filming techniques. Five films were required to capture the whale collection within the context of the exhibit hall. An informal evaluation of four quality levels pixel density for one of these videos is given in Table 5 below. The videos show the Humpback and Sei Whales on the left and right respectively. The recorded down-load times are reported for comparison only. They were recorded between 18-18:30 on a high-end machine connected to the Internet using a 2000k broadband connection. All of videos can be viewed using QuickTimeTM. The 1st 3 have QT zoom technology implemented, while the 4th requires the ZoomifyTM technology (http://www.zoomify.com). Unfortunately, the Zoomify video was incomplete at the time of this writing.
Table 5: Video Characteristics using a high-end PC
The videos give a true representation of the physical exhibit and the zoom function can be used to help isolate individual skeletons for study. However, multiple videos are required to capture the whale collection and the presentation maintains the visual chaos of the overlapping skeletons, while also capturing the other specimens on display in the rooms. The fixed camera position used gives a single angle perspective of each object in the room distorting both the room and the proportions of the large skeletons.
Production costs for rotational video are high in both time and money, since this presentation approach requires advanced technical skills and equipment when the rooms are literally full of the exhibit items. This results in less flexibility for adaptation to changes in the exhibits. Finally, for good visual quality, the user must have high-end technical presentation equipment, which limits the potential audience.
Given these negatives, we have found that rotational video does not give a satisfactory or economically accessible overview of our exhibit.
Using video for individual skeletal presentation
Another use of video for presentation of individual skeletons is to develop a set of item videos, as defined above, for each species. There are several options, a video along the length of the skeleton a track video or some form for 3D imaging. A track video preserves the proportions of the skeleton and can give a visual experience of the length of the large animals, which we believe will be an effective way to present the large scale of the skeletons.
We have experimented with use of a high-quality, though generally available, digital camera with movie functionality. Our Nikon Coolpix 4500 digital camera, is an unsophisticated model that probably most museums can afford as standard equipment. The movie function of this camera takes 15 high resolution, 320x240 pixel, images per second, in QVGA format that is compatible with most video presentation systems such as Quick TimeTM. The film (video) is comparable to animated films and is sufficient for filming inanimate objects. A 20 second track video is adequate for presentation of the 14m (45ft) humpback whale skeleton.
The principle advantage of this approach is the quick and inexpensive production of each item video. Museum staff should be fully capable of producing good quality videos using the fairly standard technical equipment, thus eliminating expensive contracts to professional photographers and the necessity of using advanced technical equipment. Production of the item videos is time efficient, requiring only a few minutes for filming to Web presentation.
A problem with filming museum specimens is the bleaching caused by using flood lighting. We have experienced that, for our camera, the shooting of single images without a tripod demanded extra lighting while fairly good video sequences can be produced in normal daylight or with only a little extra light.
The principle problem we experienced was that the small, 9.5*7cm (3 _ * 2 _ inch), images blurred at double presentation size and thus do not support the zoom quality required for researchers.
Using a collage for skeletal presentation
Smaller scale skeletons, less than 5m (17ft), that have free space around them can be captured in a single image and thus do not require video representation. However, photographing these single images (with our camera) required both a tripod and delayed shutter function or a lot of extra light. A less laborious technique, that will give single images of similar quality as the video, is to use the Ultra High Speed functionality of the Nikon camera. This function takes up to seventy 320 240 pixel images in video quality in approximately 2 seconds. The demand for light for this function is approximately the same as for video with the same camera.
Only a very small wide-angle lens can be used with the Ultra HS functionality of this camera. Therefore images must be taken at quite a long distance in order to capture the whole whale skeleton in one image. For example, a distance of 6.5m (22ft) was needed to capture the complete skeleton of the 5m (17ft) killer whale and 4.7m (16ft) was needed for the 4.4m (15ft) beluga (numbers 19 and 21 in Figure 4). The killer whale is in fact the largest skeleton that can be pictured in one image with this camera.
The Ultra HS technique is intended for filming objects in motion. If we move the camera instead, we can produce up to 70 rather good quality and slightly different single images. For comparison with the videos listed in Table 5,
Figure 2 shows the first and the two last images of a 69 image Ultra HS sequence of the head of the humpback whale. The quality and variation of these images can make them useful for both researchers and students in an initial study of the skeletons.
Figure 2: Humpback head collage
Unfortunately, the Ultra HS images are not good enough for advanced morphological investigations. For that kind of study probably only single images with good zoom quality will be adequate. Nor do we find the HS technique suitable for the general public who will probably find an assembly of 70 very similar images uninteresting or even irritating. However, elements of the series have adequate quality for single image presentation.
An initial architecture for the Whale exhibit
As any exhibit, the Whale exhibit can be thought of as having three parts: an introductory page presenting the source and intention of the exhibit, an overview map of the whale collection that supports selection of the information about the various species, and a set of species presentation pages. Our current work has been focused on determining the best, in quality and accessible cost, use of video for presentation of the large skeletons in our physical exhibit.
When choosing video presentations, a trade-off is required between video quality and the resources required to attain it. As noted above, it has proved both difficult and expensive to capture the Whale Hall of the Natural History Museum in a rotational video, since the physical exhibit has so many large and overlapping specimens. We have also experienced that acceptable quality videos of the individual skeletons can be made quickly by the museum curator using a relatively inexpensive digital camera with film/video functions. Though zoom functionality is not ideal with this option due to the low pixel density of the images.
Therefore our initial plan to present the collection using rotational video has been abandoned. Instead, we have chosen a more conventional exhibit design, based on a site-map which presents the Whale Hall as an architectural sketch. Item videos will be used to present both skeletal and live images of the individual whale species.
Our current exhibit design, shown in Figure 3, is a standard multiple story architecture. Standard html technology will be used to connect images, video and audio clips of live whales, maps and stories for each whale species to the exhibit map shown in Figure 4 below. This fan architecture has been shown to fit well with general usage of web exhibits (Nordbotten, 2000). Users with basic technology will be able to view the image and text based content illustrated on the left side of the design figure, while users with more advanced technology will be able to view all parts of the exhibit.
Figure 3: Exhibit design
Each species story will be presented with either one or more track item videos of its skeleton(s) or an image from the ultra HS sequence for the 10 small skeletons with free access (#13-20 in figure 4 and the appendix). Collages constructed from a HS sequence of the skeletons will also be included to support research use. The track videos will have a presentation time proportional to the length of the whale to help communicate the size aspect of the animal.
In addition to zoom functions, introductory images will have embedded links supporting more detailed presentations and queries to the research databases. As specified in Table 4, we also need an advanced query facility that can support comparative and calculation searches in both the text and image material in both the prepared story pages as well as in the underlying databases. There will also be information inserted to the researcher about how s/he can request that specific new video-clips be posted to the web-site.
An architectural sketch for the exhibit map
The architectural sketch of the Whale Hall, shown in Figure 4, has been chosen for the exhibit map. In this sketch, the gray tones identify the two major categories of whales: light gray baleen whales, dark gray toothed whales. The number key identification is given in the appendix.
Figure 4: Sketch of the Whale exhibit
Each whale functions as a link to its species story. Using the html pass-over function, the whale s name and skeletal length will be given as an aid to location of the desired species story. The exhibit map page also includes a set of links to frequently asked questions as well as an invitation to enter a question to the system. In a future version of the exhibit, calculation queries, such as which are the largest whale species, will be supported.
Using an architectural sketch rather than a rotational video as the exhibit map for this exhibit gives a number of advantages. Visually, the sketch provides an easily interpreted overview of the physical exhibit, showing both the category and relative sizes of the whale species. Navigation is intuitive and simple as standard Web structures/links are used. Standard side bar navigation will support quick return to the exhibit map reducing the lost in space feeling of the viewer. Finally, the gray-tone sketch can be represented as a small file, supporting quick download and presentation times.
We are currently developing a set of track videos for the skeletons in the collection that are timed so that video length is proportional to the length of the skeleton and have begun to explore further the opportunities supported by different video techniques for presentation of the large objects. In parallel, we are adding research data, images, and text and video stories to the underlying databases and exploring alternative Web presentations. A demonstration of the exhibit will be available by mid-March 2003 at http://nordbotten.ifi.uib.no/VirtualMuseum/WhaleExhibit/demo.htm.
The Whale exhibit is an application of some of the techniques being developed in a joint research project with Bergen Museum, Virtual Exhibits on Demand . The project, presented at http://nordbotten.ifi.uib.no/VirtualMuseum/VMwebSite/VEDweb-site.htm, is funded by a grant from the Norwegian Research Council. Nine students and several researchers and museum staff are or have been working on aspects of this project and have contributed to the ideas presented in this paper.
Global Reach, (Sept.30, 2002, accessed Jan.6,2003). Global Internet Statistics (by Language). http://www.glreach.com/globstats/
ISP-Planet (July 30,2002, accessed Jan.6,2003) Worldwide Broadband Trends. http://cyberatlas.internet.com/markets/broadband/article/0,,10099_1435681,00.html
Nordbotten, J. (2000). Entering Through the Side Door - a Usage Analysis of a Web Presentation. Proc. Int'l Confr. Museums and the Web 2000. Archives & Museum Informatics, 2000. p.145-151. Also at (consulted Nov. 2002) http://www.archimuse.com/mw2000/papers/nordbotten/nordbotten.html
Zoomify (1999-2002). Zoomifyer for Flash. Consulted Nov.22, 2002. http://www.zoomify.com
Museum sites (accessed Jan.14,2003):
Bhutan Fortress of the Gods at www.bhutan.at
The Hermitage Museum virtual tours at http://www.hermitagemuseum.org/
The Mysteries of Catalhoyuk! at http://www.smm.org/catal/home.html.
The Natural History Museum in Maastricht at http://www.nhmmaastricht.nl/
The Sport of Life and Death: The Mesoamerican Ballgame at www.ballgame.org/
Voices of the Colorado Plateau at http://archive.li.suu.edu/voices/
The Whale collection at the Natural History Museum of the University of Bergen
This Table relates to the whale numbers in Figure 4: the architectural sketch of the Whale exhibit