Ans Licht geholt - Dokumentation von südwestfälischen Bergwerken und Untertageverlagerungen

Thank you very much for allowing me to speak in this beautiful format. Today I would like to show you some aspects of the documentation of these already described plants. You are familiar with mining. We have a lot of it in Westphalia. You have a picture of it. There are two colleagues in a mining chamber of the Kubebunde Kubei Siegen. The underground layouts are not well known to everyone, but in principle or in the first place the NS installation underground, in order to be able to store production facilities that would otherwise have been threatened by the Allied air force. You may know the best-known example, the concentration camp memorial in Mittelbau-Dorau in Thuringia. And that is simply not just a facility for a company in the NS time, but it is also a concentration camp and therefore also a very important place of commemoration. In East Westphalia, Potter Westphalia, we have such a facility that is definitely worth a visit. I can only recommend. But there are many more of these facilities, for example also in South Westphalia. Here we have the so-called Schwalbe 1 facility. Air fuel should be produced here. Here is another picture in very large-scale stables and routes. And these facilities are also an object of archaeological memorial care. Because we actually have several main topics that concern us with underground. One is research, of course, but we have much more to do with the fact that these facilities are endangered. For example, like here, you see a section of the route in an abandoned area that is slowly threatened to collapse. And if it is not documented, it is simply gone in 10-20 years. And a much bigger problem, of course, is traffic safety activities. So, for example, here is a newspaper article from Siegen, an air-raid shelter Stoll. So we have a kind of Twitter here. We have a facility of the NSZ for the protection against air attacks. And at the same time, the mountain man was assigned. It is destroyed by filling it up. And we usually have very little time to document these facilities. Usually just one day, sometimes two days, but that's not very much. And we have to document these facilities in a qualified way within a short time. The problem is also the aspect that most of the finds that are there in this atmosphere are not mountainable. You see here, for example, a shovel, which has already completely fallen apart, soft wood. We can only document them during the day, because the mining is not possible without fixing the material beforehand. You can imagine that, of course, the conditions are not optimal during the day. It is mostly narrow, it is slippery. Here you can see a very deep shaft next to it, which is filled with water. Due to the difficult accessibility, you can hardly bring any material with you. And it is always or mostly an incredible mess. Of course, this also means that the material that you take with you, the way of working, the way of proceeding, have to be adjusted to these hardnesses. Here is a little impression of what it looks like afterwards. So it's not always that easy. I would like to show you three general methods of measurement and two methods of photographing during the day, which we use in such a way, which have also developed as practicable. Here you can see the simplest method, which is the so-called hanging stuff measurement. You bind a thread between two points in the cavity, which I want to measure. Then, with a compass, the direction of this thread is determined. And to see on the right of the picture, with this arc, the rise or fall of this thread is documented. And I can measure the extension of this cavity with the sine function and especially by measuring the thread. Sounds complicated. That's why a little time lapse, which I owe to my colleague from the Deutsches Bergbaum Museum Bogen. Here the thread is tensioned. Before that, you had to make two hooks into the rock face. The colleague just hung up the compass. Then now the arc. So, and now he can sit down and start calculating. If the colleagues get the threads away, it all takes a while. It always pulls like that. And now comes the tape measure. Now they hang the tape measure on it and measure it. So an important content of this time lapse is to show you. For these two points, in principle, it is simply a vector, which I then have from the cavity. I need a lot of time, but I can work with a very simple and very effective device to this day. The representations that I can gain from this look like here on the left. I usually have so-called basic cracks. So I can limit a cavity. And then it is done like this. You make so-called cross-sections in certain areas. So what does the cavity look like? What do I have in there? And these drawings are still important today. Because photography is also possible in confined spaces. Here I put the photo in front of you. Because I just can't take the position, how I can implement that in the drawing. Not always possible in photography. So this is the old-fashioned method, which is also very low-threshold. It is also often used by associations and today in cave research, because of its simplicity. In the meantime, we use Structure from Motion. Here is such a representation. This is also an idea of ​​the colleagues from the Bergbaum Museum in Bochum. Leo Kling has also beautifully illustrated this. The object is photographed from different perspectives. I always have to make sure that I keep the lens setting the same. And during the day, a very big topic, light. The light source always has to be very similar. And then you photograph. You put a crazy amount of data. And then these data have to be calculated and processed. And here is an example. These pictures, due to their overlap, can then be combined together. And as a result, different images result in the object of desire in a 3D view. As you can see here, a very nice chess hall in Siegerland. This becomes a 3D model. And from a 3D model I can then generate measurements. This is now the opposite way of working, like with the trailer, where I have measurements and then try to create a model. The method is very demanding and very data-intensive. But it gives a very attractive representation, as you can see here. Or I can work with this representation and sketch a model, where there was a steam engine or a shaft. Or, as we have now been able to realize for the Museum in Willensdorf, or with the Museum in Willensdorf, virtual reality. The machine is now rotating in this system and the visitor can then experience it in the museum through a VR headset. Structural Flow Motion is also very good because I can immediately recognize small structures. You can see a drill pipe in front of the colleague here. He points his finger at it. So that's why I'm drilling into the rock. Explosives come in and then explosives stand. These pipes remain. These small structures can be easily recognized and documented. Structural Flow Motion, however, has several important limits. You can see them here on the left. The colleague is standing in a shaft on the left. He looks up. On the right is what you see. A very high shaft. And you can already see here with the shadows and light wavelengths that I have a very strong shading there. It is not possible from the bottom of the position to document this properly with the camera and thus to make a 3D model. Here it is better to use the 3D laser measurement with this laser measuring device, which then produces measuring points directly. Millions of times, but also here again immensely a lot of data that is generated. The device has the advantage that it is light-independent. In the meantime, the systems are relatively small. They are also very robust. And by now it is also going so far that measured areas are measured during the day, as you can see here. He has a red dot now. The colleague has now measured something new. He can match that with the other picture. You see now here is such a twig. He just has to push it over there. And then the program is automated. And with that, it is already possible to represent and check things during the day, what has been measured there. So that you can get an answer, what we have there. And that's where we come to the limits of the 3D laser measurement. We have so-called point clouds. So our eye can, because there are structures that we recognize, now form objects from these many points. In reality, these are all single points. You can see a long pole here, which we are now flying along. And the model is now rotating. And everything you see now in gray, these are hollow spaces during the day, which have now been measured with this device, within a week. This pole is about two meters high. That's why you can see that this is a very immensely large facility. And now you can see, for example, we have a hollow space here, a very large structure, here another one. And these are ore-exhausted corridors, which were left behind after the mining. And you can see here, for example, these ends very briefly under the surface. And that is of course a kind of accuracy and, above all, the measurement speed, which is not feasible at all with the other methods. The problems are then the representation. Because these points have to be implemented, or networked into an attractive representation, so that you understand the problems a little. Both examples on the left. A machine photographed in the woods during the day. Everyone can see it, it looks like a mill wheel. On the right is the scan, where even the color values ​​were recorded. But nevertheless, for our observation habits, it does not have the effect like this photo. And that's why the data that comes from a 3D laser measurement always have to be prepared. Because with the SFM I have a 3D PDF with which I can work more easily. In addition, more and more photographs have to be taken, so that I can better represent the structures. As an example on the left, this is perhaps very atmospheric and a very nice picture, but for the archaeologists it is not very expressive. On the right you can see, through a clever illumination, different levels in the rock. The old miners have made the access a little easier. Of course, it is very important that this is extremely illuminated. Or as an example on the left, a photo of me. I just made a flash on the colleague around the pillar. That's okay, but the three-dimensionality hardly comes out. And on the right, a photo with different lamps, which we have brought in, it already shows the width of the room, but it does not represent it adequately in its demarcation. And that's why, in the end, there are two methods that are still suitable for us. Here, the methodology of the German Mining Museum, that I set up dozens of flashes in a room and these flashes all have to be aligned and set up. It takes a photo between 30 minutes and 45 minutes until I have set it up. Or the method that we are now using is the so-called light painting. You see two colleagues here in a hollow space. And now let's take the light-painted picture. You see a hole down below, and in front of the colleague also something, and behind the colleague a pillar. And we have positioned different people with flashlights. The observer is up there, where the photo was taken. The camera is on a tripod, long exposure, and then the rooms are painted with flashlights. And this allows me to represent large spatial depths at a relatively rapid speed and capture what I want to have. And now we are at the last point, where I want to get an overview. It is important, of course, that we not only collect this data, but we have to be able to discuss this data, also be able to discuss it with the general public and be able to represent what we want. For example, everyone will probably ask themselves, why did we make this effort with this room? This is because we have a shaft in the depths here, where material was transported up via a winch and next to the winch there was a, so to speak, it was laid out with boards, so that you could drive past it with other possibilities. And that is of course now a totally simple graphic on a photo. And the music goes much further, of course. This is what the Saxons are doing at the moment. Here we see a representation of a museum in Diepoldiswalde. For example, there was a similar situation in Diepoldiswalde. A 3D scan, this 3D scan, has been worked out very comprehensively and then brought in this Haskelknecht and this winch and the wood there with virtual reality. Which, on the one hand, allows the interpretation or discussion in the 3D room to be discussed in the audience. And on the other hand, of course, also interesting for the interested public. And with that I now come to the last slide, where you can see a group of people from a club in Siegerland. Most of the work that I was allowed to present now, we did in cooperation, for example with the already mentioned museum and also with various actors and local associations in Siegerland. Here you see the Stahlbergverein in Müsen, which I would like to thank at this point and thank you for your attention.