---
title: "Model parameters and static/dynamic processing"
canonical: "https://help.vicon.com/space/ProCalc16/12651112/Model%20parameters%20and%20static%2Fdynamic%20processing"
format: markdown
---
Parameters can be saved out from ProCalc in two ways:

- A Model Parameter is saved to an internal file that belongs with the data you’re processing.
- An Export Parameter is exported to Microsoft Excel when you process the data files.

The concept of a Model Parameter is that you can calculate a static value based on one trial and use this value in other trials. This is commonly used in 3D motion capture when a static trial is captured with more markers than subsequent dynamic ones, usually because the static trial includes markers that are difficult to capture – or have a high risk of being knocked off – in the dynamic trials.

If you select the **Model Parameter** check box on the **Parameters** tab, the parameter is saved to the **Session** folder that you’re currently processing, and associated with the subject name. For example, if you output a point or a segment as such a model parameter, you can subsequently use this as an input variable when you define your Variables. For a more specific example: you use a static medial epicondyle marker, and you create a thigh segment coordinate system based on three or more other markers (eg, a cluster attached to the thigh). You can now save the position of the medial epicondyle marker in the thigh segment’s local coordinate system as a Model parameter. Then, you can re-create this marker as a virtual marker in a dynamic trial by transforming the local coordinate of the parameter to the global coordinate system.