Imaging devices, systems, and methods for capturing and processing images for vision applications in a non-fixed environment are described herein. An example system includes: an imaging assembly, an aiming assembly, and one or more imaging processors configured to: (a) receive a first image; (b) analyze at least a portion of the first image to determine a first focus value; (c) configure a focus parameter of the imaging assembly based on the first focus value; (d) receive a subsequent image; (e) determine a blurriness value for at least a portion of the subsequent image; (f) responsive to the blurriness value being less than a predetermined threshold value, transmit the subsequent image to a decode module; and (g) responsive to the blurriness value exceeding the predetermined threshold value: determine a subsequent focus value; (ii) configure the focus parameter based on the subsequent focus value; and (iii) repeat (d) through (g).