1. A system for imaging an engine, wherein the engine comprises: a casing; a rotary shaft arranged within the casing, and extending along a longitudinal axis; a first plurality of blades arranged within the casing at a first point along the longitudinal axis of the rotary shaft, wherein the first plurality of blades are arranged around the rotary shaft and are configured to be rotated by the rotary shaft about the longitudinal axis; and a second plurality of blades arranged within the casing at a second point along the longitudinal axis of the rotary shaft, wherein the second plurality of blades are arranged around the rotary shaft and are configured to be rotated by the rotary shaft about the longitudinal axis, wherein the casing defines: a first access port arranged to guide a first observation scope through the casing at a first radial direction to the longitudinal axis of the rotary shaft to acquire image information of the first plurality of blades as the rotary shaft makes a predetermined amount of rotation, wherein the first radial direction is radially offset from a reference radial direction to the longitudinal axis by a first predetermined degree; and a second access port arranged to guide the first observation scope or a second observation scope through the casing at a second radial direction to the longitudinal axis of the rotary shaft to acquire image information of the second plurality of blades as the rotary shaft makes the predetermined amount of rotation, wherein the second radial direction is radially offset from the reference radial direction to the longitudinal axis by a second predetermined degree different from the first predetermined degree, and wherein the system comprises: a processor comprising hardware, wherein the processor is configured to: generate a first stage image of the first plurality of blades based on the image information of the first plurality of blades; generate a second stage image of the second plurality of blades based on the image information of the second plurality of blades; and align the first stage image to the second stage image based on the first predetermined degree of offset and the second predetermined degree of offset.