This calculator finds the maximum lens focal length and the appropriate minimum field of view, based on data entered for the CCD size, the distance from the lens to the object, and the maximum size of the target object to be imaged. Select the CCD size from the options in the drop box or select CUSTOM.

If CUSTOM is selected, enter the numeric value for the custom CCD size in millimeters. The standard default is 1/4 inch and the custom default is 10mm. Enter the numeric value for the distance from the lens to the target object and select the designation for distance from the drop box. The combined defaults yield 10 meters.

Enter the numeric value for the maximum size of the target object also select the designation for the size, from the drop box. The default is again, 10 meters. All calculations take place at each entry. You may however, click Calculate to update if needed.

You may click Clear Values to begin again. The result is displayed as a very accurate rendering of the maximum focal length, in millimeters, and the minimum field of view in degrees.