Among a wide range of contactless 3D fingerprint acquisition methods available today, photometric stereo based method offers low-cost and accurate recovery of 3D fingerprints. This chapter discusses such online 3D fingerprint image acquisition approach. Systematic details on such photometric stereo based setup are detailed in this chapter, i.e. from setup hardware, offline system calibration, preprocessing the raw images, specular reflection removal methods, to the choice of reconstruction methods. This chapter also shares our insights and results on the attempts made to consider non-Lambertian nature of finger surface. Resulting computational complexity for respective online 3D fingerprint imaging system also appears in this chapter.