Calculation of best focus point

Calculation of best focus point


Hi,

my question regards the calculation of the best focus point for a
situation in wich dof should extend from some near limit different
from the hyperfocal point to infinity. I know about the formula 2*X*Y/X
+Y (where X is the near limit of dof and Y is the far limit) to give
the best focus point but what value do I have to set for Y if it
should be infinity? - 0 or some negative value?

Any input very welcome!
Michael

Re: Calculation of best focus point


"Michael Quintero" <michael.quintero@gmx,com > skrev i meddelandet
news:1180182693.122864.306850@k79g2000hse.googlegroups,com ...
>
> Hi,
>
> my question regards the calculation of the best focus point for a
> situation in wich dof should extend from some near limit different
> from the hyperfocal point to infinity. I know about the formula 2*X*Y/X
> +Y (where X is the near limit of dof and Y is the far limit) to give
> the best focus point but what value do I have to set for Y if it
> should be infinity? - 0 or some negative value?
>
> Any input very welcome!
> Michael
>

The value of the expression for 'best focus point' approaches 2*X when Y
approaches infinity.

/BJ