P3D accurate math for macros

[Tom Deering <tmd@xxxxxxxxxxx>]

I've been having an off-list discussion about the 1:30 rule, and how poorly
it works for macros.  To help the discussion, I have placed several charts
on my website that show the Berkovitz geometrical calculations for maximum
lens separation in a variety of scenarios.  You can see them at the address
below.

Maybe you could print these two tables, and put them in your camera bag.
Then you could have access to good math, almost as easy as the 1:30
estimation.

Just for fun, the charts also show the 1:30 rule for comparison so that the
reader may decide how well this rule of thumb works for macros.

http://www.deering.org

Cheers,

Tom

P.S.  A photo of a piece of the "Dial M for Murder" filmstrip has been
added to my NSA photos.  Shows the two side-by-side pictures, and the sound
track.  Can't say where I got it, though.  :^)



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