How to use namespaces in XAML WPF including to refer to a converter (maybe other code too)

Place in header part of file. My initial mistake was
    xmlns:local="clr-namespace:MyConverters
Should have been
    xmlns:local="clr-namespace:OneWay.WPF.MyConverters
Need to include the assembly, even if it is the same project.
In this code local gives the namespace a short name.

Next using the namespace in XAML

<Style.Resources>
    <local:ButtonCenterConverter x:Key=”DivideByTwo”></local:ButtonCenterConverter>
</Style.Resources>