What precautions should be taken when using a Zhongze microhardness timer to ensure measurement accuracy?

When using the Nakazawa manual turret microhardness tester, there is one point that requires special attention. First, before the LED light is extinguished or while START is flashing, do not rotate the indenter/measurement conversion handle; otherwise, it will affect the indentation measurement accuracy and may even damage the instrument's needle. After the test is completed, rotate the turret so that the 50X objective lens is at the front of the main body, so that the diagonal lengths of both sides can be measured in the micrometer eyepiece to obtain the HV hardness value.