Calibration of the image is of crucial importance to measurement. On calibrated images, realistic measurements can be performed and objects of different images could be compared to each other. A correct calibration has to be made before you begin to measure.
There are two ways how to obtain a calibrated image:
To capture images with a calibrated system (objective). Please see the Objective Calibration chapter which explains how to calibrate the NIS-Elements system.
To calibrate an uncalibrated image manually:
There are two ways to calibrate an image
After you run the Calibration > Recalibrate Document command, you can specify a distance in the image or set the current pixel size. Please see Manual Calibration
When you have an uncalibrated image, you can use an already calibrated objective to calibrate it. Right-click the Uncalibrated field on the image status bar and choose one of the objectives from the Calibrate using Objective sub-menu. Of course, the same objective which was used to capture the image shall be selected.
NIS-Elements supports the following units:
pixels, nanometers, micrometers, millimeters, centimeters, decimeters, meters, kilometers, inches, mils
If the image is uncalibrated, pixels are the only units available. In case of a calibrated image, it is possible to select other units which are then used to display all values (e.g. measured length/area). There are two ways of how to select the desired units:
Right click the image status bar where the calibration is displayed. Select the units and precision from the context menu.
Or, click the Current unit button located in the Calibration > Objectives command window and select the units.