Wow! It's not often I see this technique, and with good reason, perhaps, I think it looks so difficult. Did you really dot that whole drawing? How do you know where to put the dots? They all must be so perfectly placed to look good from a distance. Well done, is all I can say.
Thank you very much - the technique is more time consuming than anything else. Because the dots are so slight, it is easy to cover up if a mistake is made. The black background is more of a stippling technique, broken up by the white circles.