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This paper investigates off-equatorial plane deflections and gravitationallensing of both null signals and massive particles in Kerr spacetime in theweak deflection limit, with the finite distance effect of the source anddetector taken into account. This is the effect caused by the fact that boththe source and detector are located at finite distances from the lens, whilemany researchers often use the deflection angle for infinite distances fromsources and detectors. The deflection in both the $\phi$ and $\theta$directions is computed as power series of $M/r_0$ and $r_0/r_{\mathrm{s,d}}$,where $M,\,r_{\mathrm{s,d}}$ are the spacetime mass and source and detectorradii respectively, and $r_0$ is the minimal radial coordinate of thetrajectory. The coefficients of these series are simple trigonometric functionsof $\theta_\te$, the extreme value of the $\theta$ coordinate of thetrajectory. A set of exact gravitational lensing equations is used to solve for$r_0$ and $\theta_\te$ for given deviation angles $\delta\theta$ and$\delta\phi$ of the source, and two lensed images are always obtained. Theapparent angles and their magnifications of these images, and the time delaysbetween them are solved and their dependence on various parameters, especiallyspacetime spin $\hat{a}$ are analyzed in great detail. It is found that theregenerally exist two critical spacetime spin values that separate the case oftest particles reaching the detector from different sides of the $z$ axis fromthe cases in which the images appear from the same side in the celestial plane.Three potential applications of these results are discussed.

Off-equatorial deflections and gravitational lensing. I. In Kerr spacetime and effect of spin