I worked with a professor on my final year project who has now left the college to finish his Ph.D. He is currently working as an assistant professor at some other college. As I worked closely with that professor, I thought of asking LOR from him. But, as he left my college, his official email ID is of the other college. I will not be able to ask for a letterhead from my college for the LOR written by the professor from another college. Does a LOR taken from such a professor affect my admission process?