Welcome to the world of push processing. What you saw is exactly what happens when you push. Contrast increases and highlights block up. The reason is that extending the development causes increases in the density in highlight areas more so than in shadow areas.(posted 9074 days ago)If you are trying to get more grain but without sacrificing contrast, try shooting delta 3200. I haven't shot much of it but people around here seem to have good results rating it at about 1600. I'm not sure about processing times. Look around the forum and you will come across someones recommended developer and processing times.