VSI AC-19, Semiautomatic minirhizotron camera system. The system is designed to be operated in horizontally or flat-angled installed MR tubes as commonly installed in rhizolabs and other experimental installations holding large amounts of minirhizotron tubes. The dual view system (i.e. 2 cameras on opposite sides of the imaging unit) is wirelessly programmed with the MR tube number via a tablet computer and placed on a gear rack slightly protruding from the MR tubes. After initialization, the AC-19 camera module is independently and precisely taking photos at pre-set positions (set via a tablet computer) before returning to the home position. This allows an operator to run 2-3 camera modules efficiently in parallel - being only tasked with changing camera modules between tubes and setting the MR tube numbers via scanning RFID tags with the handheld. Images are saved in ultra-high resolution (2500 dpi) and with the ICAP naming scheme on one of two USB sticks (16 GB) per camera module and can thus be transferred anytime to a laptop etc. The battery of the camera module is chargeable and replaceable for virtually unlimited time of operation. The software allows to pre-set imaging positions in bulk or individually per tube, taking e.g. differently protruding MR tube length into account. The circular gear rack position can be manually changed with magnetic end caps (indexing heads) at the end of tubes (to image the complete inside of the MR tube). Gear racks can either remain in tubes (most convenient) or can be interchanged between tubes (to save set-up costs). Check out the MS-190 manual minirhizotron, or the fully automated AC-21 minirhizotron imager for different root imaging solutions in situ.