# Technological Development and Application of Photo and Video Theodolites
## 2 Technological Development
### Development from 2001 until Today
The integrated cameras in both models had a 5 MPx CMOS image sensor, with fixed focus and an FOV of 15.5\({}^{\circ}\)\(\times\) 11.7\({}^{\circ}\), with the possibility of recording video at 20 fps [45; 46]. Figure 8: First commercial IATS from Topcon (GPT-7000i) [41], from Trimble (VX Spatial Station) [43], from Pentax (Visio model R-400 VDN) [44], and from Leica Viva (TS11/TS15) [45]. It should also be mentioned that, at the beginning of this commercial period when IATS systems were brought to the geodetic scene, the first IATS instrument was actually presented by Sokkia (SET3110 MV) at INTERGEO 2002. The instrument had two integrated cameras, an overview camera on the telescope and another camera integrated in the telescope. The curious aspect of this instrument was that it did not have an ocular; instead, the expert performed measurements using a remote controller displaying the live video obtained from the integrated cameras. In 2013, Leica introduced the new series called Nova with two models TS50 and MS50. The instruments, in addition to an overview camera, had an integrated camera in the telescope with an FOV of 1.3\({}^{\circ}\)\(\times\) 1.0\({}^{\circ}\), an 8\(\times\) digital zoom of the overview camera, and a 30\(\times\) optical zoom of the telescope camera, as well as an 8\(\times\) digital zoom. That way, the images from the telescope camera were magnified 30\(\times\). Leica MS50 also had a scanning function with the ability to scan 1000 points per second. Leica TS50 did not have a scanning function. Both models used the same motorization using a servofocus drive. On the basis of the scanning function with video and photo capture capabilities, a combined approach to image analysis and scanning was developed [47; 48]. In 2015, Trimble introduced its state-of-the-art IATS model S9 which used the same camera and image sensor as Trimble VX Spatial Station introduced in 2007. However, the S9 comes in at least 10 different possible configurations. The S9 replaced the VX and S8 for both precise and long-range applications. It offered higher angular and distance accuracy than the VX Spatial Station [49]. The predecessor of today's state-of-the-art IATS and IASTS company, Topcon, unfortunately abandoned its original design with two integrated cameras in the instrument; in 2014, it offered IATS model DS-200i with one camera, an overview ultra-wide camera on the telescope with a 5 MPx image sensor, which was mainly integrated for providing imaging documentation and a live video stream on the remote controller [50]. In Table 1, Leica TS60, Trimble S9, and Topcon DS-200i are compared with their main specifications and characteristics. These instruments do not offer a scanning function as they are classified as total stations not multi-stations, although S9 offers a combined model with a scanning function. Today, Leica offers the models TS60 and MS60 from the Nova series introduced for the first time in 2015 with improved functions of ATR (ATR plus), reflector self-search using the PowerSearch function, dynamic look function, motorized direct drives based on Piezo technology, improved scanning function with 3D laser scanning of 30,000 points per second, image-assisted surveying, and documentation using advanced artificial intelligence; it is called the first self-learning multi-station [51]. Trimble introduced its new generation of IATS instruments in 2016, model SX10. This is the first commercial TS, i.e., IATS without an ocular. Three 5 MPx cameras (overview, primary, and general) are integrated in the telescope, offering a maximum total FOV of 360\({}^{\circ}\)