Nasib Makarim and Arabic calligraphy

Nasib Makarim is in my judgement the best Arabic calligrapher of the last two centuries.  So much of the Arabic calligraphy out there are attempts to mimic his style.  So much of the Arabic official insignia and loges and official signatures were designed by him.  I also like that Ottoman calligrapher who designed the official seal of the Sultan: what was his name?