In recent years, digital cameras have become one of the tools used by the new generation due to their unique advantages in capturing and processing data and usage in many applications, such as crop growth, forest monitoring and archaeological investigation. The quality of images captured by digital cameras originate from accurate measurements which are allied to the digital internal camera parameters. Instability of geometric cameras require consideration to achieve good accuracy in measurement. Therefore, camera calibration becomes an important task to ensure the stability of all internal camera parameters. This research is aimed to assess the internal camera parameters of non-metric cameras. The quantitative method was adapted by this research, which required an experimental implementation achieve quality in data acquisition. Several camera parameters needed to be emphasised in regard to camera calibration, which consisted of focal length, offset main point, radial lens distortion, and distortion of tangent lenses. The offset main point represents the image centre coordinates while the distortion of tangent lenses ensures image quality during image acquisition. The study found that Nikon SLR D60 camera provided a higher accuracy as compared to DJI 4 pro and iPad