New command for spacing letters in microtype

Question

How can i make a new command that increases the space in between the letters. I do not want to use the already existing commands like \textsc, \Large or \footnotesize; and if it's possible I prefer a command with an argument ...

\documentclass[a4paper]{memoir}

\usepackage[italian]{babel}

\usepackage[T1]{fontenc}

\usepackage[babel=true,tracking=true]{microtype}

\SetTracking{ encoding = *}{ 400 }

\begin{document}

\textls{this is a test}

\end{document}

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Is it possible recreate this setting in microtype with the new command? LetterSpace=40 WordSpace=2

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Look at my answer and tell me if the commnet are rigth please. Thanks. whith this configuration i have the default letter spacing in all text and command, so no influence on any part of the document right?

\documentclass[a4paper]{memoir}

\usepackage[tracking=true]{microtype}

\newcommand{\textlsLarge}[1]{{\Large\textls[400]{#1}}}

\begin{document}

\textlsLarge{this is a test} % new spacing command that use the space specified in newcommand (400)

{\Large this is a test} % no influence on the large command 

\end{document}

Answer 1

Quoting section 7 of the microtype manual:

By default, each character will be spaced out by 100/1000em=0.1 em; this amount may be altered in the optional argument to \textls, using the \SetTracking command, or globally with the letterspace package option, with decreasing significance in this order.

Based on \textls, you may define custom commands that letterspace to a smaller extent than the default setting, and also commands like \textlsLarge. Note that font size switching within paragraphs may lead to improper line spacing.

\documentclass[a4paper]{memoir}

\usepackage[tracking=true]{microtype}

\SetTracking[no ligatures = f]{encoding = *,shape = sc}{120}

\newcommand*{\textsomels}[1]{\textls[40]{#1}}

\newcommand{\textlsfootnotesize}[1]{{\footnotesize\textls[800]{#1}}}% Note additional group!

\newcommand{\textlsLarge}[1]{{\Large\textls[-100]{#1}}}% Note additional group!

\begin{document}

\textsc{this is a test}% uses letterspacing as specified in \SetTracking above (120)

\textls{this is a test}% uses default letterspacing of 100

\textsomels{this is a test} 

\textlsfootnotesize{this is a test}

\textlsLarge{this is a test}

\end{document}