I ordered a Kasina and it's on the way. I want to use it primarily for concentration meditation. What would be the best program for that? Normally, when wanting to concentrate people stare at a disk on a wall (a kasina) using an afterimage develops, then they closed their eyes and focus on observing the afterimage. At some point focus gets so strong they a propelled into a jhana. Can MindPlace Kasina be used to access jhana?