
The spatial frequency response (SFR) has long been a crucial metric for evaluating imaging quality, particularly in camera performance assessment. However, the constraints of chart-based assessment limited the evaluation of natural scenes, making it challenging to evaluate resolution accurately in real-world environments. Notably, the development of the natural scene spatial frequency response (NS-SFR) has enabled resolution evaluation from natural scenes, extending its utility to diverse applications. Nevertheless, existing NS-SFR methods have been limited to two-dimensional analysis, neglecting depth-dependent behaviors such as variations in sharpness across focal planes. To address this limitation, we propose a depth-aware extension of NS-SFR, integrating depth dimension into modulation transfer function (MTF) analysis, and establish a model of the depth-MTF relationship that derives a representative MTF value for a single image’s resolution. Our approach extends conventional planar NS-SFR analysis into a 3D depth-augmented framework that accounts for depth-dependent variations in MTF. Also our results suggest that our approach enables a more resilient and informative methodology for accurate cross-sensor comparison, yielding predictions that show a reasonable correspondence with resolution tendencies observed in natural scenes, while enhancing robustness under varying illumination.