The scale of a drawing, map, diagram or image is the ratio of the linear dimensions of objects reflected on them to the real dimensions of the same objects on the ground or in nature. If it is a diagram, engineering drawing or map, then, usually, an indication of the scale is a mandatory requirement for this kind of documents. But sometimes it happens that the scale is not known, so you need to determine it yourself.
Instructions
Step 1
Just in case, check, maybe you just didn't notice this inscription. In diagrams and drawings, it must be indicated in the stamp. It can be an inscription in full format "Scale 1:20" or abbreviated "M 1:20". On topographic maps and diagrams, the indication of the scale is also an obligatory element of the out-of-frame design. It can be indicated in the title of the card, which is located at the top or bottom. Sometimes the scale label is located in the text of the map legend or directly on it. Review the diagram or map carefully.
Step 2
If you did not find the indication of the scale on the diagram of a machine-building part or building plan, which indicate the dimensions of the part in centimeters or measurements in meters, then you can determine the scale yourself. Measure the dimensions on paper with a regular ruler in millimeters or fractions of a centimeter. Divide the value indicated on the diagram and converted into millimeters or centimeters by what you got when measuring. This will be the desired denominator of the scale of the drawing or plan.
Step 3
Similarly, you can find out the scale of a map or topographic scheme. To do this, you need to carefully look at the map and identify a couple of characteristic objects located on the ground. For large-scale maps, these can be buildings, boiler pipes. For small-scale maps and diagrams, you can use the tops of hills and mountains, road forks, and other characteristic points of relief and terrain. Measure the distance on the map between these characteristic objects with a ruler.
Step 4
If you have a map of the same territory with a known scale, then measure the distance between the same characteristic points on it and recalculate the scales. If there is no such map, then use the mapping services Yandex or Google. Find this area using satellite images, which are the basis of these services, and determine on it the same characteristic points that you found on a map or diagram. Select the Ruler tool, measure the distance in kilometers from space images and calculate the scale of your map using this data and the distance measured on the map.
