So you got a sizing at Velopez and want to know more about those numbers. Use this page as a reference for your needs in the future. And of course, feel free to contact me with any questions anytime.
Center of Bottom Bracket
A couple of the following measurements are measured from the "Center of The Bottom Bracket". Here is a picture of what that is.
This is measured from the center of the bottom bracket to the "top" of the saddle. The "top" of the saddle is both subjective and inconsistent between saddles. So when you measure this take your tape measure or ruler from the center of the bottom bracket along the saddlepost and up to where ever the saddle top ends.
This will be different by up to a centimeter, or even more, depending on the saddle you have on your bike. So get it to within a centimeter of the height you chose during the fit and see how it feels.
Take a looking at the image to the left for a visual of this dimension.
This refers to how far back the nose of your saddle is from being directly above the center of the bottom bracket. I used a laser level in the studio to quickly measure this, but you likely don't have access to that. You can use a long level or simply a second tape measure to approximate a straight line through the center of the bottom bracket upwards. When you are at the level of the saddle nose, simply measure from the nose to whatever you used for a straight line.
It's a little tricky, but worth doing right since your legs will be in a great position when you have the saddle height and setback in a good place.
This refers to how much below the saddle you like your handlebars. The measurement is taken directly upwards from the handlebars to the height of the top of your saddle.
Like saddle height, this dimensions is based on the top of the saddle. It's hard to have any consistency for "top" of saddle between different saddles, or even between multiple measurements of the the same saddle. This is a terribly subjective dimension. So anything based of of the saddle top has about a centimeter of play. Try to select the same spot you used for saddle height. See the image to the left.
And below you will see the handlebar drop in a visual example.
Saddle Nose to Hood Trough
This one is the least generally understood. This is a measurement of how long you want your "cockpit" to be. More helpfully, it is the distance between your rear end and your hands. Measure this from the nose of the saddle to the brake hoods. Or, more specifically, to the center of the "trough" of one of your hoods. Just choose either left or right and measure roughly to the center of the trough as seen in the image here.
Hopefully this helps answer any questions you have. Please email me if you have any other questions!