After completing the draft and specimen calendar, Tư Thiên giám submitted it to the King. With the royal approval, Tư Thiên giám started to producing different kinds of calendar for the royal court. The “Imperial Calendar” (Ngự lịch) was made for the King, with a single version only; “Dragon-Phoenix Calendar” (Long phụng lịch) for the worship at Thái miếu, Chí Kính điện and Chính Cung miếu; “mandarinate calendar” (quan lịch) for courtiers and mandarins from central to local echelons; and “folk calendar” (dân lịch) for villages and communes.
Following the King’s approval, the Royal Observatory rewrote the manuscript, and assigned some superintendents to take care of the writing and editing.
Then, the papers were overturned and glued on woodblocks. The woodblocks were carved to keep the writing. After the Royal Observatory checked both the negative and positive, papers were applied on the ink-stained woodblocks and brushed to make the text appear. Printed sheets were folded in half and arranged in page order for binding and numbering.
Finally, the Imperial Calendar was stamped with the King’s seal, the mandarinate calendar with the King’s seal and the Royal Observatory’s seal, and the folk calendar with the Royal Observatory’s seal.
The calendar-presenting ceremony was solemnly held at Kính Thiên Palace’s dragon yard. The Ministry of Rites placed the King’s seat in the middle of the Palace’s door, with full arrangement of royal equitage, ceremonial music and flags. In the early morning of the 24th day of the twelfth lunar month, courtiers and officials, in full court dress, lined up in the dragon yard to pay respect to the King. A mandarin approached the table of calendars, covered with yellow paper, and knelt to offer the King with the calendar.
After the calendar-presenting ceremony in the dragon yard, the royal recitor, kneeling in the middle of the yard, read the King’s edict to give calendars to mandarins. The courtiers and officials expressed their gratitude and the King went home. Then, on behalf of the court, the officer of rites presented calendars to all mandarins in the dragon yard. The bureaucrats knelt down to receive the calendar and raised it to their forehead to pay respect to the King. The mandarinate calendar helped courtiers and officials know the Court’s activities and ceremonies as well as the government’s working schedule.