Green Reading with the 'Zero Line'

This concept of green-reading is only 100% accurate on a planar slope; meaning a slope that is one continuous gradient and does not have localised humps and borrows. That said, it is still a priceless concept to work with. 

This is a massive tool to use when reading the greens out on the course. You start by finding the zero line: just stand where you think you have a straight uphill putt (you will be surprised how good you are at this), from there, you will have a pretty good idea of how your ball will curve from its position on the chart.

Here are the relative curves with some key notes:

Chart taken from Aimpoint

• The closer you are to the zero line, the straighter the putt becomes.
• Note that the two biggest curves are at right angles to the zero line.
• Note that the balls 2, & 10 situated just above the perpendicular curve as much as the ball on the perpendicular points (3 & 9) due to them being downhill. 
• Downhill putts curve more than uphill, therefore balls 2 and 10 curve more than their uphill opposites, 8 and 4.

Putting Course

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