Aerial photography, aerial photographs of the area, types of aerial photography and aerial photographs of the area. What is aerial photography

If you have a task of operational mapping, surveying of gas pipelines, oil pipelines or power lines to determine their condition - our specialists will quickly and on time complete this work for you anywhere Russian Federation. Our unmanned aircraft are equipped with high-quality Camera with a resolution of 24 megapixels, a thermal imager with a resolution of 640*480 pixels and a video camera with HD resolution with a tenfold zoom, which allow you to perform planned and long-term aerial photography. To carry out the work, our organization enters into an agreement with the Customer for the provision of aerial photography services. For high-precision work, the UAV is equipped with a dual-frequency GPS/GLONASS receiver that uses most advanced GPS/GLONASS technologies and is capable of tracking satellites even in difficult environmental conditions.

And, of course, we are ready to process the received materials to prepare a photographic plan, photographic diagram, or perform decryption.

An example of an orthophotomap with an area of ​​14 km * 14 km, taken from a height of 1.5 km from a Supercam-350 UAV in one day

The essence of aerial photography

Aerial photography of an area is a set of works that includes various processes from photographing the earth's surface from a flying aircraft to obtaining aerial photographs, photographic diagrams or photo plans of the area taken. It includes:
1. preparatory activities, consisting of studying the area to be photographed, preparing maps, designing aircraft flight routes and calculating elements of aerial photography;
2. actual flight survey work or photographing the earth’s surface using aerial cameras;
3. darkroom work on developing the film and making positives;
4. geodetic work to create a geodetic basis on the ground, which is necessary to correct distortions in aerial photographs that arose during the process of aerial photography, linking aerial photographs and for drawing up photographic diagrams and photoplans;
5. photogrammetric work, which is carried out both in the field and office periods, and is associated with the processing of aerial photographs to draw up plans and maps of the area taken.

All these processes are closely related to one another and partly overlap each other. Aerial photography of each site must be carried out by the same organization from inception to delivery of the final product. As a result of this work, contact prints, block layout reproductions of aerial photographs, photographic diagrams or photographic plans are produced, compiled according to the geodetic basis. All these aerial photographic materials are subsequently used to solve a number of issues in the field of forestry and the forest industry.

History of aerial photography of the area

Unmanned aerial photography, like history itself, develops in a spiral: in 1858, while flying in a hot air balloon over Paris, Gaspard Felix Tournachon took the world's first aerial photograph, and already in 1887, the French photographer Arthur Batut developed and performed the first unmanned aerial photography with using a kite. Then the ideas of unmanned aircraft rapidly developed in aerial photography, which resulted in the patented “Method and means for photographing landscapes from above” using carrier pigeons of the German pharmacist Julius Neubronner. Moreover, this method was indeed widely used during the First World War. And only on April 24, 1909, the “First use of a motion picture camera mounted in a heavier-than-air aircraft” happened during the filming of the short silent film “Wilbur Wright and His Airplane.” Currently, aerial photography is taking another turn in its history, becoming unmanned again.

Planned and future unmanned aerial photography of the area

During planning shooting, the camera is directed vertically downwards, at right angles to the surface of the earth. In the photographs we see a flat picture (orthogonal projection), reminiscent of the image on geographical maps. With this type of aerial photography, we can determine the relative position of objects on a plane without taking into account their heights. When photographing real estate, we can see those parts of buildings that are directed upward (roofs). This type of shooting is mainly used to create photographic plans. A similar product can be obtained using satellite and traditional aerial photography.

In perspective (overview) photography, the camera is directed at an angle to the horizon. This type of survey is impossible for satellites and traditional “large aviation”. With perspective aerial photography, in the images we see a three-dimensional picture (axonometric projection): not only the roofs of buildings, but also the side surfaces (walls). Thus, we can judge not only the relative position of objects on a plane, but also their shape. In addition, with perspective photography, we can determine the height of objects relative to each other. At certain perspective shooting angles, the horizon line may be present in the frame. In this case, we get the opportunity to see in one picture how a site or structure fits into the surrounding landscape and their relationship with distant objects (distant objects, forests, reservoirs, settlements). Panoramic images, including full 360-degree panoramas, can be assembled from multiple perspective images taken by rotating the camera around a vertical axis. Creating aerial photo panoramas is only possible using a specially equipped remote-controlled helicopter capable of hovering for a long time at a certain altitude while adjacent frames are being filmed.

Stages of aerial photography work

The experience gained in the use of aerial methods in surveys shows their exceptional effectiveness compared to traditional methods of collecting information, both in terms of significantly reducing labor intensity and reducing survey time, and in terms of the breadth of coverage of various types of information necessary for design. Aerosurveys are carried out in three stages: preparatory, field and office.

During the preparatory period, the topographic information available for the survey area and aerial survey materials from previous years are collected, on the basis of which the range of variations of competitive route options is substantiated and a project for the production of aerial surveys, field and office aerial photo-geodetic works is drawn up.

During the field period, the following is carried out: ground geodetic work to create a plan-altitude justification for aerial surveys; securing and marking points of the support network; different kinds aerial photography, georeferencing and interpretation of aerial photographs. An important type of aerogeodetic survey is deciphering - identifying (detection and identification) and disclosing the content (cognition) of various objects and terrain elements from their images in photographs, their qualitative and quantitative characteristics, unique properties and features.

During the office period, they perform full processing of the results of geodetic measurements, photogrammetric thickening of the geodetic survey justification using analytical phototriangulation methods, stereophotogrammetric work to obtain information about the relief and produce topographic plans and digital terrain models (DTMs) in unified system coordinates

Equipment for unmanned aerial photography

As a rule, modern unmanned aircraft operators use in their daily work a small unmanned aircraft with a span of up to 3 m with a conventional, household or studio camera based on a CCD matrix. The most popular point-and-shoot cameras are Samsung, Sony, and Pentax. Photographs from such devices are generally suitable for drawing up plans and diagrams. Aerial photographs provide significantly higher quality SLR Cameras- here the leaders and the standard are the Canon 550D and its older comrade Canon 5D Mark II. In this case, of course, large multi-lens systems are also used.

Flight survey work performed by a camera based on a matrix sensor (CCD) is more reminiscent of the traditional analogue method of aerial photography, when all elements of the matrix are simultaneously exposed. In this method, the intra-pixel geometry is known and strictly defined. The current problem with matrix technology is that large matrix lattices are difficult to manufacture. Therefore, they combine: they make large gratings from several small ones. For example, out of four. The four-element lens produces four separate images, which are transformed into a central projection and automatically stitched together. Such images are processed using existing analytical processing programs.

Second main part, and no less important, is the system for determining the position of the UAV/camera in space. In the simplest case, this is a regular small-sized GPS receiver with an antenna, for example Ublox. Currently Russian manufacturers complexes with UAVs are almost universally switching to receivers of signals from satellite positioning systems of the combined GPS/GLONASS type. Unfortunately, they cannot provide the required accuracy. Therefore, in more expensive and serious devices, an additional high-precision GPS receiver is installed, which allows, during post-processing of raw data, to determine the coordinates of the center of the image with an accuracy of 5-10 cm.

And if this receiver is used together with ground-based GPS base stations, then the accuracy of fixing frames to coordinates will increase to stunning!!! 5 cm. To carry out the survey, GPS base stations are created, the data of which is used to calculate differential corrections when determining the trajectory of the aircraft. To determine the trajectory of the aircraft and refine the angular data of the inertial system, a method of joint processing of GPS data and inertial system data is used. Linking images to coordinates is usually done using programs written specifically for a specific type of receiver and UAV. The use of this calculation method increases the accuracy of determining both angular parameters and location.

GPS/GLONASS navigation accuracy and system features automatic control UAVs allow you to achieve the following parameters when flying along an aerial photography route:

Transverse displacement from the route axis - ± 10 m;
keeping the UAV at a given height - ± 15 m;
distance from the designed photography center to the camera shutter release point - ± 5 m;
change in the UAV roll angle along the route between two images - 10°;
change in the pitch angle of the UAV along the route between two images is 6°.

Technology

The result of digital aerial photography of the area is digital aerial photographs, as well as elements of external orientation recorded in flight (linear - Xs, Ys, Zs - coordinates of the photographing center; angular - α, β, γ - camera orientation relative to the coordinate axes).

In accordance with the laws of central design, according to which the image of the terrain is constructed, the aerial negative (aerial photograph) contains a number of distortions, the magnitude of which is determined by the angle of inclination of the optical axis of the aerial camera and fluctuations in the terrain. Elimination of these distortions is carried out in the process of their computer photogrammetric processing, and in particular - photographic or digital transformation, called morphing. In this regard, the use of aerial photographs without their preliminary transformation for cartographic (topographic) support of the work performed, including as a basis for GIS, is limited by the influence of these distortions.

The readings of special instruments and equipment recorded during aerial photography provide stabilization of the camera in flight or subsequent determination of the spatial position of aerial photographs in an absolute or relative coordinate system for the purpose of their subsequent use when performing photogrammetric work and converting aerial photographs into plans and maps. Such devices include gyroscopes, global positioning systems, equipment for determining flight altitude, elevations between photographing centers, as well as aeronautical systems, etc. The presence of these data largely determines the technology of office processing of aerial photography materials, significantly affects the efficiency, accuracy of photogrammetric constructions and volumes of field work to ensure them.

Route planning

Aerial photography can be area and linear; in area photography, in addition to the longitudinal overlap of the images, it is also necessary to observe the transverse overlap. The initial parameters of photography using a drone are the required image resolution, the resolution of the aerial camera, the angle of view of the camera lens, and the amount of frame overlap. From this data, the flight altitude, speed of the drone and the camera shutter frequency are calculated.

Flight and photography

During flight, the drone automatically calculates its speed and shutter frequency (frame rate) to ensure the specified frame overlap. The overlap of UAV images meets the usual requirements for aerial photography and is typically 60% of the frame. UAV images overlap by 60% in longitudinal overlap and 30% in transverse overlap.

Quick viewing of the results of aerial photography of the area. As a result of the flight, a set of photographs and telemetry data are generated, which include the coordinates of the photographing center, as well as roll, pitch and heading angles.

Stages of processing aerial photographs in photogrammetric software

1) Creating a project (name, coordinate system, object height range, placement in the resource system);

3) Import orientation from metadata;

4) Interior orientation (Creating a camera passport);

5) Import of external orientation;

6) Formation of block layout according to external orientation;

7) Network measurement (UAV triangulation machine, tie point machine with specified parameters, support justification measurement), control;

8) Network equalization (calculation of systematics, self-calibration, control measurements), control;

9) Creation of DEM (point cloud, TIN, breaklines, DEM, horizontal lines), control;

10) Transformation from images, control;

11) Working with orthophotos (cuts, brightness equalization, cutting into sheets), control;

12) (Optional) Stereo vectorization for creating 3D maps and 3D models;

13) (Optional) Creation of 2D maps.

There are three types of data processing: affine transformation of frames to create an orthophotomap of flat areas, complete orthotransformation of frames to create an orthophotomap of territories with pronounced relief, complete orthotransformation of frames to create an orthophotomap meeting geodetic scale requirements.

Affine transformation of frames to create an orthophoto map of flat areas

The program determines common points (from 50 to 1200) between each pair of images. After this, an equation is solved that includes information from all images to find the minimum standard deviation ( standard deviation) between all vectors connecting common points. Simply put, an elastic band is stretched between each pair of points, and all frames are lined up so that the overall tension of the elastic bands is minimal. In this case, the frame can only be transformed affinely, i.e. any straight line is displayed only in a straight line.

Orthophotos from an unmanned aircraft

The program determines common points (from 50 to 1200) between each pair of images. After this, the complete photogrammetric equation is solved to determine the terrain with an accuracy of 10 pixels. At the same time, the coordinates of the photographing center and orientation parameters (roll, pitch, course) are specified.

In accordance with the calculated data, all frames are orthorectified and the result is projected onto the plane. Linking to real data is carried out using data existing in publicly available cartographic resources. For example, according to GoogleEarth. The accuracy of these data in Russia is about 6 meters.

Orthophotos from UAVs

The program determines common points (from 100 to 3000) between each pair of images. After this, the complete photogrammetric equation is solved to determine the terrain with an accuracy of 2 pixels. At the same time, the coordinates of the photographing center and orientation parameters (roll, pitch, course) are specified with high accuracy.

In accordance with the calculated data, all frames are orthorectified and the result is projected onto the plane. Linking to real data is carried out based on the results of ground-based justification, which includes at least one point for every 10 frames or at least 10 points per orthomosaic. Half of these points are used for reference, the other half to confirm accuracy requirements. The accuracy of relief formation meets the requirements of the appropriate scale.

The result of the work is geotiff format files with an accuracy corresponding to the specified scale. The geotiff format includes two files - an orthorectified aerial photograph and a digital elevation model (DEM), which can be opened in any GIS program, such as ArcGis or GlobalMapper. With DEM enabled, you can form relief contours with any elevation difference.

3D terrain model

Based on the results of aerial photography, the relief is restored using photographs from a UAV. Together with DEM, it is possible to generate the relief using isolines with the required accuracy. The standard format is vector lines in ArcGis format, which are imported into any mapping system.

The company’s specialists can produce results in almost any required format. To do this, you need to specify the program in which the result is supposed to be used.

It is also possible to transfer to a local coordinate system from WGS. When performing ground-based justification, we can survey coordinates on the GGS marks (state geodetic network), then the work can be immediately carried out in the local coordinate system without conversion and a corresponding loss of accuracy.

Aerial photography of a land plot, carried out both in conjunction with geodetic work and separately from them, will provide a visual representation of the features of the area. On the resulting DTM it is possible to measure distances and volumes. This is especially important if it is necessary to estimate costs for the design of roads and communications.

Who needs aerial photography of the site and why?

Obtaining an image of the site from above will be useful in various cases. Among them are the design of roads and communications. Thanks to the resulting terrain models, it will be possible to determine the nature of the landscape, relief features, measure volume and area, and much more. This data will become the basis for topoplans of the territory.

Aerial photography will be useful for:

• Drawing up topographic plans- the data obtained by aerial photography will make it possible to assemble a 3D model of the terrain with heights, and the orthomosaic will make it possible to draw plan elements, which will ultimately turn into a topographic plan M 1:500 - 1:10,000;
• Monitoring illegal use of land- in this case, shooting from a UAV will make it possible to determine the location of actual fences, land use boundaries, real estate located on it and compare the obtained data with the real estate cadastre;
• Mine surveying of quarries- the service will allow you to draw up survey plans for quarries and dumps. The accuracy of this technique is significantly higher than traditional survey means, and the speed of work is 1-2 days for objects of several square kilometers.

Cost of aerial photography of sites

Benefits of aerial photography

• high quality, clarity and resolution of the received frames;
• the ability to carry out shooting in any hard-to-reach area;
• all-weather use;
• the ability to create panoramic video and photographic materials;
• affordable price compared to renting a helicopter/plane;
• the ability to obtain detailed data in high resolution about the size and landscape of the territory, the presence of water bodies and vegetation on it;
• mobility - a multicopter and an unmanned aircraft, with the help of which the filming is carried out, does not require much space for takeoff and landing - there is enough space for this small area land;
• fast speed of data acquisition - you will receive the result of your work in 1-2 days.

Order aerial photography of the site from Service Geo

The history of aerial photography of the area dates back to the 19th century. As this young science developed, it increasingly demonstrated the magnitude of its potential. First interesting idea was the placement of a camera on pigeons, proposed by a German pharmacist. This method of aerial photography was used during the First World War. Technologies continue to improve to this day. And it’s amazing how differently the course of the same Great Patriotic War with modern technology, so advanced in comparison with the samples of that era.

Aerial photography of World War II

In order to collect information in the Second world war Wehrmacht aviation units called “Rovel Groups” conducted aerial reconnaissance over the territory of the USSR. They consisted of high-altitude bombers, which were modified to conduct aerial photography of the area.

Right before the invasion of the territory of the Soviet state, Wehrmacht planes flew over it. The altitude of aerial photography was too high to be accessible by Red Army Air Force fighters. It was done a large number of photographs of strategically important objects Images obtained as a result of aerial photography made it possible to plan and carry out targeted raids on airfields of the country's air force. These actions brought the air force of the Red Army into virtually complete non-combat readiness at the first stages of hostilities.

Technique

The Ju-88D aircraft became the most popular in the process of German aerial photography of the Second World War. They were the ones who were subject to constant improvement. Their speed and range of action increased. Thus, German developers achieved for them a speed of 700 km/h and a range of 2500 km.

How did the process work?

The main goal Air reconnaissance activities served the interests of ground units. Before departure, they received assignments from the army leadership. Typically, headquarters received requests for reconnaissance of the enemy's front lines and near rear. Reconnaissance aircraft flew at altitudes of about 2 km and 6 km. On each sortie, there were most often two reconnaissance aircraft - one carried out aerial photography of the area, and the other detected enemy fighters, as well as anti-aircraft artillery located nearby.

The most important data obtained during this process was transmitted via radio. Sometimes text messages were dropped at the forward position of the ground unit. Such reports from the pilots, along with photographs, were immediately transmitted to army headquarters.

Role

Since the very idea of ​​blitzkrieg was based on powerful attacks by tanks and other equipment, their speed of movement had to be high. For this reason, they needed fresh intelligence data. The speed of conveying data obtained during military reconnaissance to the units themselves was very important. Therefore, reconnaissance squadrons were often subordinate to tank units. This allowed intelligence to sometimes actually transmit live reports from the scene to the troops.

The situation with long-range reconnaissance was somewhat different. The planes flew out one by one for long-range reconnaissance. The flight plan and the final route itself were drawn up by the crew commander himself as the situation progressed. He received a number of instructions before this. For example, take photographs of a specific railway junction, detect ships on a certain section of the river, calculate the location of artillery in a specified sector. Also, before departure, the required altitude for conducting aerial photography of the area was calculated. The type of film, exposure time, and camera aperture were selected.

At the beginning of the Second World War, the following tactics were used to conduct such operations. The plane occupied an altitude of 3 to 6 km and was heading to a given area. Having found the objects, he flew over them at an altitude of 6-9 km; they were usually covered by air defense systems. As the war progressed, the aircraft flew more and more often at lower altitudes. This made it possible to increase the chance of remaining undetected by radar. When approaching the object, the pilot gained the required 6-9 km altitude. Immediately after photographing, the altitude decreased sharply, and the plane headed to the base.

Despite all the security measures, losses in the ranks of the Wehrmacht reconnaissance squadrons on the territory of the USSR were large.

Night aerial photography

The Wehrmacht encountered problems with filming at night after the failure of the blitzkrieg in the Soviet Union. The front lines turned out to be stretched over vast territories. In summer, aerial reconnaissance did not experience difficulties due to the length of daylight hours. And in winter it began to get dark as early as 16:00, which gave the Russians the opportunity to move in pitch darkness. They crossed reservoirs and built bridges. Then, in 1942, squadrons were created for night filming. Then the possibilities of photographing were significantly expanded and nothing escaped the attention of the Luftwaffe. Terrain images obtained from aerial photography were widely used in planning all kinds of operations.

Technologies

Aerial photography at night made it possible to observe the night movements of detachments, fleets, and air defense. Anti-aircraft searchlights and batteries, which were hidden by camouflage during the daytime, were identified.

Over the territory of the USSR, the shooting was carried out at an altitude of 1.2-1.8 km, sometimes from 3 km. To take pictures, bombs were dropped to illuminate the area. After this, the most primitive camera was sufficient, but the camera with a focal length of 35 cm was most widely used. The main targets for photographs were airfields and river crossings. Typically, Do-215, 17 and He-111 flew on such missions on the Eastern Front.

Because there were many more opportunities on the Western Front air defense, there the flights took place at an altitude of 4-9 km with rare exceptions. The decrease in altitude occurred while monitoring the ships and monitoring the results of dropping bombs. Then it was necessary to film at an altitude of 3-5 km.

When flying, it was important to pass over objects in such a way that the presence of moonlight would help subsequently decipher aerial photographs. At the same time, such actions were risky, since the same light could affect the detection of the reconnaissance aircraft by enemy fighters.

Flare bombs

To facilitate night filming, flare bombs were widely used. They were developed by the Germans in 1943. They were dropped from different heights, but most often from 2.7 km. When triggered, they created light flashes of 40 million candles. It only lasted half a second. The intervals between dropping bombs and exposing the films were determined taking into account aircraft speeds and altitude.

It usually happened like this. Immediately from the moment the desired object was discovered, the pilot dropped such a bomb. The reconnaissance aircraft had 4-10 such charges on board. The troops below were shocked by the explosion of light, not understanding what was happening. Objects around looked much brighter than in daylight. The night ghost flew away with the photos already taken while people began to realize what it was.

Improving technology

Throughout the war, developers in Germany improved the aerial reconnaissance technology needed by the Wehrmacht. Since 1944, unique NRB 40/25 cameras have been produced. They contained metal plates that helped protect the equipment. Their optics were improved; night cameras operated faster than day cameras.

Over time, night reconnaissance began to be equipped with warning systems about enemy squadrons located nearby. Special radars examined an area 4 km long and 3 km wide around the aircraft. This protected the scout from sudden night attacks. Radio altimeters and reflectors were used. So, flying over air defense systems, the plane scattered dipole reflectors. These were strips of foil, and it was they that contributed to the confusion of enemy radars. Their missiles hit the air, and the ghost was difficult to detect by radars, since the radar screens were filled with white spots.

Modern technologies

IN this moment Aerial photography is still used today. The technologies for carrying it out have only made significant strides forward. Multicopters invented not so long ago have made the process much cheaper. They are able to shoot in almost any weather. If previously there was only aerial photography, now there are possibilities for filming on video and creating panoramic images. All this is often used in construction. Surveying allows you to provide the most important information about the nature of the landscape. During advertising campaigns related to real estate, high-quality aerial photography of the area using a quadcopter is widely used. The same method has become popular for recording mass events of a wide variety of nature. Modern aerial photography of an area using a quadcopter fully conveys the beauty and atmosphere of nature and the desired objects.

It is noteworthy that drone filming technologies have not been used for many decades. The first aircraft with cameras without pilots were kites and hot air balloons.

Aerial photography became most popular during the Vietnam War. Due to the massive use of air defense, it was too risky to often use manned vehicles for reconnaissance. It was much easier to lose small remedy than a whole pilot with a fighter.

For aerial photography, modern technology can operate at any altitude. This gives you more options in the map creation process. The methods of aerial photography have changed greatly. Modern devices often endowed with the ability to conduct planned and long-term surveys. Such devices are compact and economical compared to aircraft that were once used in WWII. They have become available to absolutely anyone, and people are actively purchasing unmanned vehicles and drones all over the world.

Aerial photography in geodesy and topography is photographing the terrain and various objects from the required distance. Photography is carried out using drones, quadcopters, drones, helicopters and airplanes. It all depends on the tasks: what is the shooting for?

Landscape photography is very popular in farming, forestry, environmental purposes, and in oil and coal production. At emergency situations, for example, in the event of a fire, or in case of chemical damage to the territory, a helicopter with special ultra-precise equipment is used to determine the source of impact.

Aerial photography in geodesy

Photographs can be taken at different heights, it all depends on the purpose of photographing and the tasks set. You've probably noticed drones being controlled more than once; this particular device is often used for photography at low altitudes. In our company modern equipment, it is attached to an aircraft and records the soil topography, the distance to the nearest buildings and structures, the presence of forest plantations, bridges, and highways. All this information is necessary when global construction, since the availability water resources, lakes or rivers, ravines, highways can lead to further deformation of the object.

Aerial photography in topography

Agree that photographs are often not enough, a detailed study of the territory is necessary, modern devices successfully filming the video. Our company’s engineers take into account the distance from the aircraft to the object, climatic conditions and weather factors, wind speed, cloudiness, frost or heat, rain or hail are also taken into account.

The processed photographs are plotted on the map by our topographers. Topographic data is carried out at different scales, it all depends on the order. It is worth noting that all objects are plotted on the map, even the smallest, seemingly insignificant ones. When developing a site, all data is required.

Aerial photography procedure

Our company carries out shooting as follows:

1. On initial stage is being studied land plot, its characteristics. Directions, distance and time for shooting are calculated.
2. Setting up the aircraft and equipment.
3. Aerial photography from a drone.
4. In an office environment, using computer technology and software, images are processed and objects are plotted on the map in the form of symbols.

Please note that the process of photographing the area and processing photographs is very labor-intensive and requires certain knowledge and skills.

Application of aerial photography

Particularly popular is photography in farms. It has become convenient to study the field area for pest damage or determine the boundaries of sowing.

Military affairs cannot do without photography; with the help of aircraft it is easy to survey the territory for the presence of enemy equipment and map the enemy’s territory.

Photographs of rare species of animals and plants that are listed in the Red Book are examined using video and photos. High-quality photographs can be seen on television and the Internet, in various encyclopedias and magazines.

Photographing individual objects, buildings and structures is one of the main conditions for successful construction design. It is not uncommon for a newly constructed building to become deformed or collapse. The reason may be ravines located in the nearby territory or highways along which large vehicles move. Our company and our specialists will accompany the customer from placing an order to putting the facility into operation. We will carry out all types of work. Our engineers constantly attend courses and trainings, learning to work with modern software equipment, which allows us to determine everything down to the smallest detail. Topographers will answer all your questions, explain everything correctly and show you everything.

Where can I order aerial photography?

Our company provides a wide range of geodesy services. By ordering terrain photography from us, you will receive excellent service, competent specialists, and topographic data on a map of the area at any scale. Our company uses individual approach to every client.

To view prices for aerial photography and geodesy, visit our company’s website. The pricing policy will surprise you, and everyone will be satisfied with the quality of the event. Please note that our company is licensed and is guided by regulatory documents, the concluded contract is a legal document that provides you with a guarantee for several years.

Renovating an apartment or house is a rather lengthy and grueling process. We make a lot of efforts to turn all our ideas into reality. But even after the main builder...

Photography of cities and towns should be carried out using aerial photography materials.

A photographic image of the area on photographic plans or photographic diagrams gives the designer a clear and complete picture of the city’s territory, intra-block development and its condition, individual buildings, the nature and density of green spaces, floodplains of rivers, ravines, etc.

The advantage of aerial photographic materials also lies in the fact that using materials from the same survey, without waiting for completion full cycle survey work, you can quickly obtain photographic plans or photographic diagrams of various scales for topographic support for the corresponding types of design and planning work.

The use of aerial photography to update and clarify existing topographic plans is of great importance.

There are mainly two methods of aerial phototopographic survey:

combined, when the contour part of the plan is obtained in the form of a photographic plan, and relief photography is carried out directly on the ground (on a photoplan) using a scale or level; stereotopographic, when aerial photographs are used to obtain an image of contours and relief using stereophotogrammetric instruments.

In relation to city photography, especially at scales of 1: 1000 and 1: 500, a combination of these two survey methods is possible, when using stereophotogrammetric instruments a plan of the situation and horizontal lines inside blocks and in undeveloped areas are obtained, and vertical surveying of passages is carried out using a level.

To obtain photographic plans (especially with a combined shooting method), they tend to use long-focus normal-angle or narrow-angle aerial cameras (AFAs) so that image displacements due to the terrain, as well as the roofs of buildings (due to their height) are in permissible limits. The choice of focal length of the AFA will thus depend on the scale of the plan being drawn up, the nature of the relief and buildings. If the aerial photograph format is 18X18 cm, you can use AFA with focal lengths 200, 350 and 500 mm. In this case, an AFA with fK = 200 mm should be used only when creating photographic plans at a scale of 1: 1000, and an AFA with fK = 350 n 500 mm should be used when creating photographic plans at a scale of 1: 500.

The photographic scale is set several times smaller than the scale of the photo plan being created. The choice of photographic scale is determined mainly by the possible magnification factors of the available phototransformers, as well as the information capacity of aerial photographs provided by the AFA. To obtain photographic plans of certain scales, the corresponding photographing scales have been established: it is known that with the same photographic scale, stereophotogrammetric determinations of the heights of terrain points are obtained the more accurately, the larger the angle of the field of view of the aerial camera. Therefore, ultra-wide-angle AFAs are widely used for the stereotopographic method of surveying undeveloped areas. However, when photographing built-up areas, it is not advisable to use these AFAs, since perspective images of buildings will cover a significant part of the passages, the greater the wider the AFA and the higher the buildings are. In particular, with fK = 70 mm and with normal overlap of images, the width of the “dead zone” will be equal to the height of the buildings. Therefore, when stereotopographically surveying built-up areas, wide-angle AFAs with /k = 100 or 140 mm are used, and in some cases narrower angles are used (for example, when surveying at scales of 1:1000 and 1:500). It is possible to use ultra-high-angle AFAs (s/k = 70 mm) for photographing built-up areas only in low-rise buildings and when performing a second run with normal-angle or narrow-angle AFAs to compile photographic plans.

The choice of an aerial camera and the scale of photography during stereotopographic photography depends on the nature of the building (number of storeys and density) and on the given height of the relief section, and, consequently, on the required accuracy in determining the photogrammetric heights of terrain points.

The relative errors of photogrammetric heights determined from aerial photographs of scales 1: 10,000 and larger are 1/3000-1/4000 at /.= 100 mm, 1/3500-1/5000 at /k= 140 mm, 1/4500 -1/6000 at /k = 200 mm.

At smaller photographic scales, the relative errors will be somewhat smaller.

Thus, for example, stereo topographic survey with. a relief section height of 1 m can provide the required accuracy of the relief image (with root mean square

error 0.30 m) at photographing scales 1: 10,000-1: 12,000 at /„=100 mm (H= 1000-1200 m), 1: 8500-1: 10,000 at /„=140 mm (#= 1200-1400 m) and 1:7000-1:9000 at /k = 200 mm (H = 1400-1800 m).

At the same time, when choosing a photographic scale, one should take into account what increase in the scale of the plan compared to the scale of aerial photography can be provided by the existing fleet of stereophotogrammetric instruments. When working on the SPR without a coordinateograph, the plan scale can only be 2 times larger than the image scale, on SD-3 - in Zraza (it can be 4, but then the coordinateograph will not be able to service the entire area of ​​the stereo pair), on SPR-ZM with a coordinateograph and on There are practically no restrictions on the stereomstrograph. In addition, for built-up areas, it is essential to photograph contours, the accuracy of the position of which will decrease if the photographic scale is reduced too much.

When shooting on a scale of 1:5000 with a relief section height of 1 m, it is most rational to take photographs at a scale of 1:12,000 with an aerial camera with =100 mm. With a continuous multi-storey building and the same section height, it should be taken into account that perspective images of buildings and trees will cover an area equal to approximately 0.7 of their height at 100 mm and approximately 0.5 of their height at = 140 mm. In this case, it is advisable to use AFA = 140 mm and a photographic scale of 1:10,000. If stereoscopic drawing of the relief is performed using aerial photographs obtained by AFA = 100 mm, then to compile a photo plan it would be advisable to perform a second flight using AFA = 200 mm at a given photographing scale 1: 20,000.

When shooting at a scale of 1:2000 with a relief section height of 1 m, it is advisable to set the photographic scale smaller than 1:8000, and in some cases even 1:6000 (when using SD-3). Therefore, photography can be done both AFA = 140 mm and AFA = 200 mm. In undeveloped areas, it is advisable to use AFA = 100 mm, then you can do sparse high-altitude training.

Longitudinal and transverse overlap, straightness of aerial photography routes and other indicators of flight quality must comply with established technical requirements.

In the built-up part of each city there are many trees and green spaces, the crowns of which in summer cover from 40 to 80% of the territory of streets and driveways on aerial photographs. Per 1 km of travel there are on average up to 45 wells of underground communications outlets, of which about 50% are covered by tree crowns. Therefore, aerial photography settlements With big amount It is advisable to plant greenery in the spring before the leaves appear or in the autumn, when the leaves fall from the trees, before the snow cover appears.

Aerial photography is carried out in cloudy weather or in the morning and evening hours, when the shadows are most transparent. When developing aerial films taken in sunny weather, excessive image contrast should not be allowed.

On the territory of cities and towns there is a dense network of points of the reference geodetic network, which must be used with combined and stereotopographic methods of aerial photography, which will increase the accuracy of plans and reduce the cost of work on the planned reference of aerial photographs.

Before aerial photography work, the points of the geodetic reference network are marked, drawing them up in the form of white squares 0.3X0.3 m or crosses with indelible paint on the sidewalks and roadways. In cities with low-rise buildings and passages without road surfaces As a marking, you can use a trench, for example, a quadrangle. The dimensions of the square are calculated so that its image on the aerial photograph has dimensions of 0.4-0.5 mm.

If the image dimensions of triangulation points exceed 0.5 mm, mark the center of the sign so that its diameter in the image is 0.1-0.2 mm. If the contrast of the sign with the surrounding background is low, it is recommended to fill the middle with lime or chalk.

Aerial photography materials are submitted for further processing in the following volume: aerial negatives numbered according to survey routes with a digital diagram, contact prints in duplicate, block layout negatives, reproductions from block layout negatives in duplicate, aerial flight passports, journals for assessing the photographic quality of negatives, radio altimeter readings and statoscopes, characteristics of the aerial camera and shutter, brief explanatory note indicating the assessment of the quality of work performed.