## 8 Conclusions  
For typical objects made of unfired bricks and blocks, often damaged and very irregular, SLAM technology is very useful and economical. In this project, the high accuracy of object points in millimeters (like it is typical with the TLS technology) was not necessary because of shape and material used from unfired earthen blocks. Most important was the speed of the documentation of the large and complex mapped units. As was written, the accuracy of the ZEB-REVO PLS was in cm and the RMS reached was typically from 2-3 cm based on the type of measured objects. The advantages are as follows: Simple and inexpensive transport, easy operation, and automatic processing into basic outputs. The existing software mainly creates a floor plan of a point cloud, which can be semi-automatically vectorized and saved in CAD formats (dwg, dxf). It is also possible to join individual models in one. Semi-automatic or fully automatic vectorization for irregular objects is complicated; there is a necessary, often essential, contribution from the operator. The simplest type of ZEB-REVO does not have a camera nor a display that would show what is being scanned--higher versions have it. Figure 27: 3D model of a wooden carved artifact (Kasbah des Caids, Tannougalt), photographed by iPhone 7 (5 min, 36 images from a distance 1–1.5 m). In this case, the created model using close-range photogrammetry was very good. The BLK360 scanner is perfect for the detailed and textured scanning of objects, especially interior spaces, or small alleys, of which there are many in the historical centers of settlement. It is incredibly easy to operate with only one button. Stop-and-go scanning is relatively fast; the problem is that you usually do not see immediately how the result looks. Control via tablet and direct automatic data processing is only possible for small and simple objects; in practice, it does not work very well. Batch processing requires relatively slow (only wireless) data transfer. The automatic connection of scans is based on correlation (it does not normally need targets), and it is functional only for some objects and requires a workstation. Nevertheless, the BLK360 scanner is an amazing advancement compared to the operation and data processing of other scanners. A novelty in 2020 is the modernization of the BLK360 into a mobile scanner (e.g., ZEB-REVO). The resulting accuracy reaches 3-4 mm on short distances up to 10 m, which is precise enough for most applications of historical constructions documentation. The automatic point cloud joining runs very well for simple objects and the joining accuracy reaches 3 mm for irregular earthen structures. Digital close-range photogrammetry is low-cost and can be the most accurate, but there are stability problems in poorly lit areas and narrow corridors. In the daytime, the outer parts of buildings are variably lit by the Sun, so it is necessary to wait for better lighting without shadows. Even sparse vegetation near the object is opaque for this technology. On the other hand, it is cheap and uses a better digital camera, which is not problematic for transport abroad. Photography is usually allowed almost everywhere, but the use of laser scanners or other professional activities can be an administrative problem in many countries. In this case, photogrammetry was used only in addition due to lack of time and poor lighting conditions. The camera used and the picture taking was not of sufficient quality; for this reason, the accuracy of the photogrammetrical result in this case reached only centimeters and the data were significantly affected by the image noise. Some photographs could not be processed due to poor lighting and poor image quality. It follows that photogrammetric work requires quality preparation and suitable lighting, which can be very demanding for indoor spaces.