Hi Martin Morton,
Thank you for reaching Microsoft Community. We appreciate for sharing your concern to us.
Pen pressure sensitivity is the ability of your graphics tablet to determine the thickness or thinness of the lines you draw based on the pressure you apply to your Surface pen. Using the Microsoft Surface App, you may adjust the pen pressure sensitivity on your Surface pen. Open the app, then select the Pen category from the list of options on the left. Change the settings for your pen by using the slider under Pen Pressure Sensitivity.
You may check the following articles below:
- How to use your Surface Pen - Microsoft Support
- Identify your Surface Pen and features - Microsoft Support
Kind regards,
Lavenia