I had previously posted on my misconceptions about how breast mass translates into cup size and have since done some additional research. There is clearly a huge amount of confusion over bra fit out there in the whole female population. Two important things I learned:
1 - Band size should fit tightly-enough that you can only put two fingers under the back strap and this should be on the loosest hook. The band should also then run level all the way around without tugging up the back or having any loose spots at the sides. The shoulder straps should not dig in at all.
2 - Lettered cup size IS NOT THE SAME physical volume at different band sizes. It increases with larger bands. An A-cup on one person could be quite different from an A-cup on another. Without band sizes considered or without having the two people standing side-by-side for reference you wouldn't have any way of accurately knowing the individual breast volume of either person. Take what anyone has to say about their cup size with caution because they could be totally wrong and/or it could have absolutely no bearing on what that would look like on your own body.
My chest measurement gave a calculated 38" band size. I bought a very nice 38A bra to try based on this (cheaply thankfully) and am finding that the band is looser than it should be based on what I now know. I think I can make it work so it doesn't go to waste but it appears I actually need a 36" band size, which I would not have expected. In particular this will affect the spacing of the cups apart and the actual cup width which is terribly important for fitting exactly over the whole breast mass as closely as possible without being too wide or too narrow. What I really hadn't understood is that it will also affect the lettered cup size such that I'd probably fit best a letter UP in a smaller band.
I will admit that my own cup size right now is mostly 'conceptual' as I'm still waiting for development there. It will make a major difference though in fit and look as I develop small or stay small if I can get this whole fitting concept correct. From what I understand right now 36A would be my maximum ideal target size so I should be able to work down from this properly during the early days of my development. As noted in my last thread there are sizes available down to AAA if you seek them out so there is ample opportunity for the lesser-endowed to feel and look great. Also, different bra brands bands (say that ten times fast!) have slightly different relative cup volumes for a given band/letter combination so experimentation is key to finding the best fit and function.
If you would like to see a proper presentation on the subject, go to the following website and view the video there:
http://www.frmheadtotoe.com/2010/08/ask-ms-bra-fitting-101.html The presenter may be VERY petite and super cute but don't let that put off any of you aspiring transitioners from watching. She's felt very uncomfortable about her tiny breasts just as much as many of us have.
