## Step 3 – Enter Calibration Pattern Information

This step allows you to enter information about your particular calibration pattern and also to choose the real-world coordinate axes within the image.

The utility will remember the parameters used most recently and fill out the boxes accordingly. This is useful if you have a single camera / single inspection setup, as you will only have to enter the information once, and not when recalibrating.

If you don’t wish to use the previous parameters, you can click the Default button to recall the values shown above.

The text entry fields are:

- Rows – The number of dots down the camera image (down in pixel space);
- Columns – The number of dots across the camera image;
- Dot Spacing (X) – The real-world horizontal distance between each dot in the calibration target;
- Dot Spacing (Y) – The real-world vertical distance between each dot in the target;
- Dot Diameter – Not currently used;

- Units – The camera has no concept of mm or inches but this value will appear in other data later on. If you are measuring in microns, enter microns. This is a text field and is not used for any math;

- Origin – Shows which dot in the calibration pattern represents the world-coordinates origin:
  - Top Left
  - Top Right
  - Bottom Left
  - Bottom Right
  - Center
  - Custom
- Memo – Can be used to store a small note about the current calibration.

Note: Choosing Origin > Custom will show two more text fields that allow you to choose which point is the origin in your target.

The Multi-Dot Calibration Utility also gives you the choice of selecting the real-world axis orientation. The software defaults to the top-left arrangement but you can select any you want to use and the camera will then report coordinates relative to the origin point according to the axis orientation selected.

Once the text fields are populated as needed, click the Next button to proceed to the next step.