The paper summarizes the methodology followed, to evaluate the accuracy of different digitization methods of ecclesiastical monuments in 3D computer vision form and stresses the importance of photographic equipment calibration. In this study, a set of images were taken using the CANON EOS M5 digital camera, while the internal calibration parameters – horizontal and vertical focal length (fx, fy), principal point coordinates (x0, y0), radial distortion coefficients (K1, K2, K3), tangential distortion coefficients (P1, P2) and the affinity and the shear terms (b1, b2) were estimated. These parameters were calculated using different software applications and then analyzed. For the calibration procedure, 3D texture models were built with the Agisoft commercial software based on: (a) the aforementioned calibration parameters and (b) the self-calibration process. The overall accuracy (Root Mean Square – RMS) between these models, by comparing known geo-referenced ground-control-points (GCP) is presented through the Cloud Compare software. The results indicate that the internal calibration parameters of the digital camera used for documentation purposes are essential and should be systematically implemented for documentation purposes.

本文总结了所采用的方法，以评估3D计算机视觉形式的教会纪念碑不同数字化方法的准确性，并强调了照相设备校准的重要性。在这项研究中，使用CANON EOS M5数码相机拍摄了一组图像，而内部校准参数–水平和垂直焦距（fx，fy），主点坐标（x0，y0），径向畸变系数（K1，估计K2，K3，切向变形系数（P1，P2）以及亲和力和剪切项（b1，b2）。使用不同的软件应用程序计算这些参数，然后进行分析。对于校准过程，使用Agisoft商业软件基于以下内容构建了3D纹理模型：（a）上述校准参数和（b）自校准过程。通过比较已知的地理参考地面控制点（GCP），这些模型之间的整体精度（均方根– RMS）通过Cloud Compare软件提供。结果表明，用于记录目的的数码相机的内部校准参数是必不可少的，应出于记录目的进行系统地实施。