Thanks for such a quick response. I've typed up a quick comparison chart of My calculations (A), Tawbaware (B), and the values listed on the Nikonians page (C). Please note, that I recently read that the Tawbaware calculations had an error in them at some point, but they do conform with several other online calculators that I have found so I think that error has been fixed.
As you can see the error listed on the far right (A minus B and A minus C) are within 1 degree. For practical purposes this is ok because at 1 meter distance (i.e. distance from target to focal plane indicator) 1 degree only translates into 1.7 cm error.
This work is all part of some new research I am working on, and I will eventually publish the results. I simply want to cross all my t's and dot all of my i's...like ensuring I don't forget to account for something like crop factor...so that the information I publish is as accurate and reliable as possible!