Sounds right to me.
For a rough estimate you can do this: put your fingertips against the palm of your opposite hand. Then press down and bend as if inserting your hand in the ball. Where (i.e. what angle) do you have to move your fingertips away from 90 degrees to the palm? The closer you come to 90 degrees (tip to second joint) the more under palm you can go with the fingertips.
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"I do desire that we may be better strangers." Willie the Shake, As You Like it(III,ii)
"Life robs us of more than death does."