What distinguishes a Vedic astrologer?

Vedic astrology is not Sun-sign astrology. The primary birth-sign around which the Vedic birth-chart is constructed is called the lagna-sign or the rising-sign. While there are many aspects that distinguish Vedic astrology from others, probably the most significant aspect is the use of, “karmic principle”.  For chart-analysis, the most powerful tool used by Vedic astrologer is the dasha system whose foundation is karmic principle. While there can be many lineages/techniques like Parashara, Jaimini, Bhrigu, Nandi Nadi, Varaha Mihira, Bhaskaracharya etc. it is dasha system that is used almost everywhere in Vedic astrology making it inseparable from spirituality. Even the modern procedure called KP uses dasha system. A Vedic astrologer follows sidereal calculation to construct birth-chart unlike a typical Sun-sign astrologer who follows tropical calculation.