Veteran filmmaker Subhash Ghai, who directed Dilip Kumar in films like `Vidhaata`, `Karma` and `Saudagar`, says working with the legendary actor has been an `evolving process` for him.

`Directing Dilip Kumar was evolving process for me for 20 years in three films. Best I learnt from him in film making - 'never loose dignity even in cheapest scene' - that makes you a dignified director as well as a man," Ghai posted on Facebook on Saturday.

Dilip Kumar, whose real name is Yusuf Khan, celebrated his 93rd birthday on Friday.

He became a name to reckon with in the 1950s and 1960s through his performances in films like "Aan", "Daag", "Devdas", "Madhumati","Paigham", "Mughal-E-Azam", "Ganga Jamuna", "Leader" and "Ram Aur Shyam".

After working for about six decades, he stepped out of showbiz in 1998 after "Qila".