Started using a dual laser park assist device mounted to the ceiling above the table to mark spots for repetitive shot practice. I centered it, at one end of the table so I can reach the pointers to adjust them. This means I am marking the top of the ball, not necessarily the spot on the cloth. The device is motion-activated, I put the sensor on the backside, which means it needs to see motion on that half of the table to be on. Might switch it around, or might just swipe the cue in the air to activate if needed. Lasers show very well, even in well lit room. You have to gauge the top of the ball to accurately place it. Will experiment with marking one end of the ball or finding ways to accurately place ball under laser spot. Hopefully the bright lasers shining off the balls isn't an issue with the eyes. If anyone else tries this, be sure you understand the effects of lasers on the eyes and follow the rules.