Photo-generated 3D models are noisy mainly due to low-quality input photos or limits in the 3D reconstruction process.
Blurry, overexposed, or unevenly lit images confuse the algorithm, leading to misinterpreted textures/depth and grainy surfaces. Too few photo angles force the software to "fill in" details, adding noise.
To cut noise, use sharp, well-lit photos from more angles—this gives the algorithm clearer data for accurate mapping.