I'm from Bombay, India. And have just started playing pool since the past 2 months. I am also handicapped (I have the right eye with perfect vision, while the left eye has about 25% vision), despite the same I have gone on to win a tournament held recently in the intermediate skill players section. I have a query for you. I have had a lot of problems in judging the angle of deflection required for a cut shot. Could you guide me and tell me what I can do about it.
Regards,
Eurico Rodrigues

It's quite predictable, Eurico, varying directly with your ability to hit the cue ball exactly where you're aiming to. What you're basically asking about is called the 90-degree rule, or Rule of Tangents, and it goes like this.

When you strike the cue ball in its exact center, with a level cue, it begins to move in a SKID, before commencing to roll naturally. How far it skids, with neither forward nor backward roll, is a function of how hard you hit it. But if it's still skidding when it strikes the object ball, it will deflect 90 degrees from the object ball's path.

If, however, the cue ball is rolling naturally at the point where it contacts the object ball, it will deflect LESS than 90 degrees. How much less has to do with speed, but typically, about 15 degrees less.

If you've drawn the cue ball, so it still has backspin on it when it contacts the object ball, the deflection path will EXCEED 90 degrees. Again, by how much depends on speed.

Sidespin on the cue ball is not thought to affect the Rule of Tangents. In my experience, however, inside English (that is, cue-ball spin on the same side as the direction of your cut shot) in combination with draw produces the widest deflection angles of all.

It's easy enough to demonstrate this quickly: put an object ball on the foot spot, where the balls are racked, and hang another object ball in a side pocket, the same side of the table where you plan to pocket the first ball. Note that the angle formed by lines between the corner, the object ball and the side is just about 90 degrees. Now place the cue ball somewhere where you have a modest angle to the corner, cut that object ball in, striking the cue ball dead in the center with some authority, and I'd have to bet the mortgage you make the ball in the side too.

This is one of the cornerstones of position play. Not only does it let you see where the cue ball should travel, but what you need to do to avoid interfering balls or scratches. It does need some fine-tuning, in terms of applying your own sense of speed, allowing for cue ball/object ball "cling" (friction), etc. But once you get used to visualizing this, your game should expand almost at once. Good luck and good shooting, and special thanks for writing from so far away. GF
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