Errors in the correction of Chinese maps

In the course of class or answer questions of group friends, often encountered the problem of Chinese map correction, the most common is that we get the following data correction.

Pictures from Baidu Pictures, no actual geographical significance.

See similar to the latitude and longitude of the picture, to its raster data rectification, a lot of people get his correction method is directly input latitude and longitude to rectify. This is in fact a wrong approach. Because the input latitude and longitude to correct this type of map, it is the default bar this data is considered a latitude and longitude data. In fact, the type of frame used for this data is this:

The coordinate type of this frame is the projected coordinate system type, which is the Jarpos projection (Albers) using the equal-product conic projection. So this data correction should use the frame to correct, instead of using the input latitude and longitude correction, and do the frame is to pay attention to the scale and ellipsoid type, already conformal or equal product. Some graphs also have different selection of standard parallels.

If you want to use latitude and longitude to rectify, the shape of the Chinese map should be like this

Errors in the correction of Chinese maps