Explanation In general, the size of the feathers displayed on your monitor does not correspond to their natural size. Therefore, most of the  presentations of feathers on this website show a ruler with a millimeter scale. This offers the possibility to calculate the zoom of your browser necessary to display the feathers in natural size. In order to determine the value of the zoom one has to messure the distance A (in millimeters) between two points on the ruler which represents a distance of 10 cm, e.g. betweeen 8 and 18 cm or 7 and 17 cm. Then divide 100 (mm) by A (the distance in millimeters). Example 1: If the distance between 8 an 18 cm on the scale on your monitor is 200 mm, then you have to devide 100 by 200. The result is 0.50, that means the zoom of your browser has to be set to 50 % to see the feathers in natural size. Example 2: If the distance between 8 an 18 cm on the scale on your monitor is 90 mm, then you have to devide 100 by 90. The result is 1,11, that means the zoom of your browser has to be set to 111 % to see the feathers in natural size. Zoom (%) = (100 : A) x 100 (%) The zoom value given in the presentation of the feathers on www.ornithos.de\Feather_Collection is calculated for the use of the Microsoft Internet Explorer and a monitor with 1680 x 1050 pixels. For return to the website www.ornithos.de\Feather_Collection click on the return buttom of your browser.