Approach

Choice of objects

We thought it would be interesting to incorporate two objects that were distinctly disparate in chronological origin but similar in function, structure and texture. Browsing through the Institute of Makings Materials Library, we chanced upon the Fiestaware Cup and Pewter Teapot, and decided they fitted the bill of what we were looking for.

This is because while they belong to very different eras - the cup was first introduced in 1936 while the teapot was manufactured a lot earlier, in 1760 - there are many similarities between the two objects. Both have the same functionality as tableware and while the Fiestaware cup is a brightly coloured orange whereas the teapot has a dull grey body, the texture of the two materials is smooth. Also, neither piece is safe for use despite their makers original intent because of the toxicity of their materials; the Fiestaware cup contains uranium oxide, which makes it radioactive and the teapot contains leaded alloys that is toxic if inhaled or digested.

We thus felt that the combination of the two objects would beautifully illustrate an integration of material culture across time periods that allude to how tableware has evolved in design over the years. Fig. 1 is a visualisation of one possible way to combine the objects.

This choice of objects and resultant combination is but one of the multiple possibilities that a museum visitor can come up with. The permutations and combinations of objects are limited only by a visitors imagination; visitors can make choices as they deem fit, whether it be similar objects from different eras or different objects from the same eras etc.

Process of scanning

Technology: Low cost scanner

We first attempted to scan the objects with the low cost scanner but due to the glossy, dark surface to the teapot, it was difficult to achieve a high-quality scan of the teapots body, let alone its intricate details. We attempted multiple scans (Fig. 2) and even consulted Gui Fens expertise but were unable to capture a satisfactory scan (Fig. 3). As such, we decided to employ a more advanced scanner the Nextengine scanner.

Fig. 2 Fig. 3Technology: Nextengine scanner

We next attempted using the Nextengine scanner for 3D imaging. In terms of usability, the Nextengine scanner performed significantly better than the low cost scanner. It was easier to operate since the scanning process was automated and we did achieve a decent scan of the teapot (Fig. 4). However, it failed to capture some parts of the teapot, causing the fragmented look of the scan (Fig. 5). We learnt that this was because of the scanners size limitations. The Nextengine scanner is optimal for objects below a certain height, which the teapot exceeded and thus, the quality of the resultant 3D image was merely average.

Fig. 4Fig. 5

Given its lack of precision, we were reluctant to proceed with the fragmented 3D image and hence went on to try high-resolution photogrammetry, in the hopes for a 3D image of higher quality.

Technology: High-resolution photogrammetry

Since the photogrammetry software, 123D Catch, was available on both phone and laptop, we initially shot a loop of sequential photographs in small increments around the teacup with an iPhone and inputted these photographs into the software. Before we captured the photographs, we predicted potential problems that might affect our result and arranged our setup accordingly to avoid them. Specifically, we tried to account for:

1. The reflective surfaces of the objects, specifically in the case of the teacup given its particularly glossy surface By carrying out the photography in a uniformly lit area to eliminate reflectivity in our photographs2. Noisy background images By limiting the depth-of-field of our photographs3. A lack of scale in the 3D image By placing rulers adjacent to the photographed object so that they too will be captured in the image and thus provide a means of measurement

Fig. 6 shows the first 3D image of the teacup that we obtained. Comparing our result to other scans in the Catch gallery, we realised the extent by which the photographs quality affected the scan quality. We hence repeated the photogrammetry process with a DSLR camera and achieved the scan in Fig. 7.

Fig. 6Fig. 7

For the teapot, we were handed a set of photographs from another group that they had captured while practising handling a DSLR. The resultant scan (Fig. 8) however was unclear due to the fact that the photographs were taken in poor lighting (Fig. 9). We thus re-photographed the teapot (Fig. 10) and ended up with a better quality scan as seen in Fig. 11.

Fig. 8Fig. 9

Fig. 10Fig. 11

Although photogrammetry is more tedious than using the Nextengine scanner as we have to manually ensure that we photographed all angles of the object, the overall result from photogrammetry is much more desirable in our case. With these scans (Fig. 7 and Fig. 11), we proceeded to editing the 3D images.

Process of editing

Software: Meshmixer

At this stage, we wanted to combine the scans to form a new object as depicted in Fig. 1. We started off by smoothing out the rough edges of the scans. Then, to separate the handle, lid and sprout (Fig. 12) from the body of the jar, we used the plane cut and make slices tools in Meshmixer. We exported these individual parts into different layers before appending them onto the body of the cup to create a new object (Fig. 13).

Fig. 12 Fig. 13

We found Meshmixer to be non-intuitive and as such, it took some practice before we familiarised ourselves with the programme. It was helpful that the software is relatively well documented and there are tutorials online that we could access whenever we needed. It crashed frequently as well, causing us to lose unsaved work occasionally. Another challenge we encountered in Meshmixer was the specificity of file format that it required. In order to combine different parts of the object in Meshmixer, the imported files have to be in .ply, despite the fact that the default file format of 3D images typically being .stl. To overcome this, we had to go through an extra step of converting the files into the right format.

Resource: Thingiverse

The final object we envision included some ancillary parts, specifically braille lettering and a stand. We first attempted to create this ourselves (Fig. 14) but given our limited exposure to Meshmixer and time constrains, we did not possess the proficiency to create an object stand and braille lettering from scratch our creations lack uniformity, making them unsuitable for printing. However, we still wanted to include these components in our 3D prototype as we felt that they were crucial elements in As such, we sourced them from Thingiverse (Fig. 15). By importing the relevant templates into Meshmixer and manipulating them to suit our purpose, we managed to include these components in our object as we envisioned (Fig. 16).

Top, bottom: Fig. 14, Fig. 15Fig. 16Reflections on successes: Key decisions that contributed to our success

A large part of our success can be attributed to the fact that we allocated enough time to attempt using all three 3D imaging technologies. This enabled us to determine which method best suited our objects. By paying attention to the factors that impact the quality of the image from photogrammetry (e.g. quality of photography, number of photographs used), we ensured that our resultant 3D image would be of the highest quality. Additionally, by being self-aware of our capabilities in 3D imaging and deciding to employ readily available resources i.e. Thingiverse, we saved time and effort without comprising on our idea/final 3D print.