A standard lidar survey produces a point cloud consisting of the topographic information (e.g., position in x,y,z) and the intensity (I). Thus far, the intensity information has not been used and no calibration methods have been available. As the lidar intensity data can sometimes be the major (or only) source of high-resolution brightness information from a particular area (especially in the polar regions), there is a growing interest in more effective intensity calibration methods. This would enable more cost-effective and accurate method of laser-based brightness measurement. We have developed a calibration scheme for airborne and terrestrial lidars, based on calibrated brightness targets (grayscale) for airborne and laboratory use. The first results point out that this type of test targets can be used in both airborne and laboratory laser brightness calibration. More information on the research group: www.fgi.fi/envilaser.