The arrangement for determining features of a hot surface during manufacturing process of a product, comprising a light source, camera, control unit for the camera and light source, image-processing unit and server, wherein the camera is arranged, controlled by the control unit, to take a number of successive images of the surface to be photographed, whereby each image comprises a part of the surface to be photographed, the camera and the surface to be photographed being arranged to move relative to each other such that each image comprises a part of the surface part shown in the preceding and the following image, the light source is arranged, controlled by the control unit, to illuminate the surface to be photographed from the side direction relative to the camera, whereby the camera and the light source are synchronized in such a way that the light source illuminates the surface at the moment of shooting the image or for part of the moment of shooting the image, the image-processing unit is arranged to combine a complete image of the whole surface to be photographed out of the successive images taken by the camera, the server being operatively connected to one or more measuring devices, the server is arranged to determine a coordinate system for the complete image, to receive from the one or more measuring devices data on the surface to be photographed, generated by the one or more measuring devices at different stages of the manufacturing process, and take into account those coordinates and proportions in the received data which deviate from the complete image and match them, to visualize the received data in the complete image formed of the target to be measured in that area from which the measuring data has been obtained. the camera is arranged, controlled by the control unit, to take a number of successive images of the surface to be photographed, whereby each image comprises a part of the surface to be photographed, the camera and the surface to be photographed being arranged to move relative to each other such that each image comprises a part of the surface part shown in the preceding and the following image, the light source is arranged, controlled by the control unit, to illuminate the surface to be photographed from the side direction relative to the camera, whereby the camera and the light source are synchronized in such a way that the light source illuminates the surface at the moment of shooting the image or for part of the moment of shooting the image, the image-processing unit is arranged to combine a complete image of the whole surface to be photographed out of the successive images taken by the camera, the server being operatively connected to one or more measuring devices, the server is arranged to determine a coordinate system for the complete image, to receive from the one or more measuring devices data on the surface to be photographed, generated by the one or more measuring devices at different stages of the manufacturing process, and take into account those coordinates and proportions in the received data which deviate from the complete image and match them, to visualize the received data in the complete image formed of the target to be measured in that area from which the measuring data has been obtained.