# A Methodical Approach to 3D Scanning of Heritage Objects Being under Continuous Display
## 5 Results and Discussion
### Case Study 1--\"Snake\"  
In the case of the \"Snake\" figure, the scanning time was 20 min. During this time, 9 partial scans of both sides of the figure were made. The number of partial scans was dictated by the need to increase the repeatability of scans due to the \"difficult\" surface of the object--glossy black stone with a small number of characteristic areas. Dealing with  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Case Study Number** & **1** & **2** & **3** \\ \hline Object name & “Snake” & “Icon of Saint Nicholas & “Buddha” \\  & & of Myra” & \\ \hline Place of scanning & Tashkent, Uzbekistan & Romania & Tashkent, Uzbekistan \\ \hline Scanning environment & Ad hoc studio & On the site & On the site \\ \hline
3D scanner used & Artec Eva & Artec Eva & Artec Eva \\ \hline Scanned object type & A & B & C \\ \hline Scanned object dimensions & 26.3 \(\times\) 23.6 \(\times\) 4.4 cm & 87.1 \(\times\) 64.9 \(\times\) 3.7 cm & 74.6 \(\times\) 65.9 \(\times\) 29.6 cm \\ \hline Partial scans number & 9 & 4 & 20 \\ \hline Rejected scans number & 1 & 0 & 2 \\ \hline Raw scan total size & 0.98 GB & 0.38 GB & 5.28 GB \\ \hline Scan average accuracy & 0.5 mm & 0.6 mm & 0.4 mm \\ \hline Problems with obtaining color and texture & NO & NO & NO \\ \hline Object surface digitized & 100\% & \(\sim\)50\% & 85\% \\ \hline
3D base model size & 27.2 MB, 394.5 KTri & 150.5 MB, 1.03 MTri & 62.1 MB, 886.8 KTri \\ \hline
3D dissemination model size & 10.6 MB, 145.9 KTri & 25.1 MB 250 KTri & 10.9 MB, 150.7 KTri \\ \hline Preparing time & 10 min & 10 min & 10 min \\ \hline Scanning time & 20 min & 12 min & 45 min \\ \hline Restoring time & 10 min & - & 15 min \\ \hline Processing time & 3.5 h & 1.5 h & 6.5 h \\ \hline Obtaining 3D base model time & 2.5 h & 1.0 h & 5.3 h \\ \hline Obtaining 3D dissemination model time & 1.0 h & 0.5 h & 1.2 h \\ \hline \hline \end{tabular}
\end{table}
Table 2: Results of 3D scanning for the case studies.  
this challenge required maintaining a relatively uniform distance between the scanner and the object surface. Expecting the occurrence of glare and breaks in the scanned surface, the scanning of each figure side was repeated several times.  
During the data processing stage, the obtained partial scans underwent processing and assessment. It lasted 2.5 h. As a result, one scan of unsatisfactory quality was rejected due to the occurrence of significant gaps and visible reflections on the saved texture. The remaining 8 scans were used to generate the high-quality base 3D model (Figure 7--on the left). The obtained model covered 100% of the \"Snake\" figure area--there were no areas that could not be digitized. The obtained mesh density allowed for a good reproduction of the object's shape and cavities (Figure 7--on the right).  
It took another 1 h to prepare the dissemination 3D model (Figure 8) for the purpose of publishing it on the 3D Digital Silk Road Portal [39]. The time spent is mainly the result of finding a balance between the model quality and providing fair performance for the viewers. The performance aspect was very important as the model was published within a larger collection on a website offering a dedicated 3D viewer. Other actions concerned polishing, converting and publishing the model to meet the requirements of the portal.  
It was the simplest of the use cases. It can be seen from the shortest preparation, scanning and restoration times, which were no longer than 20 min. Due to the small dimensions and simple shape, the size of scans was the smallest, just as the processing time leading to the 3D base model. To conclude, in this case, the applied methodology turned out to be fully sufficient.