Re: : RE SUB PIXEL Estimation

Goldsmith, Noel writes:
>Calvin asks about sub-pixel measuring.
>
>Yes its possible.
> ...
>The keeping everything the same, repeat the process with your unknowns.
>And it might sound easy but it is very difficult to keep everything the
>same.


Indeed.  Also, consider this: before you spend a great deal of trouble
trying to get sub-pixel measurements, be sure that you know the
difference between precision and accuracy.

In this group, it's tempting to bring up the concept of "empty
magnification'. 

It's possible to "find" edge locations to whatever precision you like.
The question is: are you gaining any ACCURACY?

-- 
Kenneth Sloan                                            sloan@xxxxxxx
Computer and Information Sciences                       (205) 934-2213
University of Alabama at Birmingham                 FAX (205) 934-5473
Birmingham, AL 35294-1170                http://www.cis.uab.edu/sloan/