How to correct the time difference and time zone in the astrolabe correctly

Time zone is the most error-prone place to make a life table. Because China is a vast country, spanning several time zones, but all use Taibei time, there are inevitably errors in time. As we all know, the shortest time for the sun to project on the sundial is at local noon 12. At this time, judging from the horoscope, the sun should coincide with the transit. At present, only Beijing can adopt the -8 time zone (in fact, Beijing is not completely -8), and other regions need to correct the time difference before entering the correct birth time.

For example, someone: 1976, 8, 27, 0: 53 was born somewhere in Inner Mongolia, with latitude and longitude110e140N48. We first input all the data according to the -8 time zone, and then adjust the birth time to 12, and we will find that the sun deviates greatly from the transit, reaching more than 10 degrees. Then adjust the time zone to make the sun closest to the transit, and the result is -7: 18 (note: the progress of the time zone is 60), and then enter the correct birth time, and you will find that the rising point has moved more than 9 degrees. This chart is the real chart when this person was born. (Twelve constellations/Astronomy/)

Generally speaking, as long as the place of birth is not too far from Beijing (in longitude), the time difference can be ignored, and -8 can be used. However, if the birthplace and Beijing span more than one time zone, especially in remote places such as Xinjiang, the time difference must be corrected first, otherwise there will be great errors.