Re: Reciprocity Problem

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> *** Technical Answer Follows **
> ** press delete key if technical questions bother you **

----- Original Message -----
From: "Jeff Dilcher" <root@hiddenworld.net>

> I am trying to develop a mathematical function which will
> help determine reciprocity compensations.

As MS says, that is a good thing!!

> Initially, I would like to be able to submit a small set of
> reference values (metered exposure times along with
> exposure time compensation for reciprocity). Using these,
> I would like be able to enter in any exposure value, and
> get a corresponding compensated value on the reciprocity
> "curve".

That curve is known as BEST FIT.

> I am trying to boil this down into an algebraic equation
> as easily as is possible. I have quickly reached the
> endpoint of my math abilities. Can anyone provide a clue
> for me?

Here is a clue: what you want to accomplish is known as REGRESSION ANALYSIS
which give you as a result an equation for the BEST FIT CURVE, books on
those topics will teach or refresh your knowledge on that. Since you
mention the words "as easily as possible", another way is to use one of the
many REGRESSION ANALYSIS programs available (some shareware, some freeware)
which will save you the tedious calculations needed. One program easy to
use and very good IMO is "Regression Analyzer", you can read about it here:
http://www.mfsoft.com/equationgrapher/

Guillermo
Received on Tue Jun 19 12:37:40 2001