Shared inputs, different charts
Both approaches can use a birth date, time and place. A natal astrology chart reads planets through signs, houses and aspects. Human Design maps astronomical positions to gates and lines and calculates BodyGraph connections. The same birth information produces different symbolic outputs.
An ascendant is not a Human Design type
A type such as Generator or Projector is not translated from a Sun sign or ascendant. Type considers defined centers and complete channels. Two people with the same sign can have different Human Design types; two people with the same type need not share a natal chart.
Why does Human Design use two layers?
Personality uses birth; Design uses an earlier moment determined by an 88-degree solar arc. Activations from both are read together. The Design moment is not another birth date or a way to select a different ascendant. Colors such as red and black distinguish layers rather than good and bad.
When reading both systems
Define your question and keep each concept within its own system. Do not assume that a center directly corresponds to an astrological house. This Starmora calculator produces a Human Design BodyGraph; do not assume it calculates houses or an ascendant. Symbolic interpretation remains separate from calculation accuracy.
Sources and approach
Original Starmora text. Consult these sources for traditional system concepts.