We have now completed all the remaining 3D production sessions and have approximately 60 objects from Te Papa filmed in 3D. It was an incredible experience working with artefacts ranging from eighteenth century woodcarvings to delicate twentieth century ceramics, New Zealand taonga and Pacific masks. Paul and Miriam’s favourite object was the `aumakua hulu manu Küka`ilimoku. In total around 70 students, colleagues, partners from outside Victoria University and staff from Te Papa took part in the sessions.
As the sessions went on we found that we got to grips with the technology more quickly and our set-up times were greatly improved. Nonetheless, the process of aligning the cameras using the near and far techniques (described here) was still a delicate process that involved fine-tuning on each occasion we ran a session. It has certainly proved the filming in 3D requires endless patience and careful attention to detail.
The extensive set-up time meant we always favoured trying to work with one type of lens rather than changing the lenses and therefore going back through the camera alignment process again. In the initial sessions we experimented with 18mm, 35mm and 50mm lenses before settling on 35mm for the remaining sessions. Even when we filmed our tallest object, Samurai armour (Sendai-do no Gusoku), we found that the 35mm lens worked well.
With the camera lenses fixed, the main variables that we worked with were the distance of the cameras from the objects, the interaxial separation of the cameras and the convergence point. The distance from the objects was mainly determined by the size of the object as we wanted each one to fill as much as the frame as possible. However we did experiment with different distances to see how they would change the sense of the object’s scale when it was played back on the 3D monitor. The most challenging object was, of course, the Samurai armour as we were using a 35mm lens that meant we had to get the camera rig as far away as 4 meters from the armour in order to get in all in the frame. This was no easy task in the limited space we had at Te Papa’s photography studio, particularly as the white backdrop we were using no longer filmed the frame. Luckily, we managed to get the object in the frame in such a way that we were able to film it effectively.
When it came to choosing the convergence point, this was normally located somewhere centrally on the object and we set the depth of filed to encompass the object from front to back. With some of our wider objects, such as the Eharo dance mask, we found that the extremities of the object would end up out of focus. Sometimes this meant we would have to shift the convergence point or play around with the other variables until we found a solution that worked. As with everything in 3D, we often sought a visually pleasing compromise that could emphasise the depth relations of the object without losing sense of the detail on its surface.
The other main aspect that we experimented with was the interaxial distance between the cameras. Although the human interocular distance between eyes is normally 65mm, our interaxial was mainly determined by the size of the object and its distance from the cameras. We frequently experimented with interaxial distances that were smaller and larger to see how it would help us visualise the depth planes in each object. Sometimes we found by increasing the interaxial distance, we had a great sense of the object coming out of the screen but this could also mean the object would look artificially elongated. All of this helped us understand that we are not asking the cameras to act as exact substitutes for our eyes; instead they are helping us created a stereoscopic visual field that emphasises the depth contours of objects in ways not possible in 2D filming.
Although we were happy with the way almost all the object transferred into stereoscopic space, we were particularly happy with the work we did on various Pacific masks. The feathers, fibres and other textured materials in many of these masks had a great sense of detail and tactility when reviewed on the 3D monitor. Even more so than the other objects, there was a sense that we could reach out and touch them.
As always, the 3D production experience was enriched by the conversations we had with Te Papa staff. They were able to elaborate on the cultural significance of the objects and the specific materials they were made from. Although it will be hard to translate all of this information into our final visual pieces, we hope that the rich textures and the detailed craftsmanship of the objects will be apparent. The next stage is post-production work that will result in some final pieces for 3D enabled screens.