Here is a new paint.net tutorial where I will explain how to create a parchment paper as the ones from the Middle Ages. Then, you could use it as a start for medieval style creations. It is quite simple to realize this effect with paint.net. I am quite sure you will be impressed by what you can obtain from this software.
Here are the steps to follow in order to create a parchment from scratch :
1/ We start from a transparent sheet;
2/ We select the area where we want to create the parchment (S) and then we select DED898 as primary color code and EFE6C0 as secondary color code;
3/ We perform a clouds effect (effects menu > render > clouds) with the following parameters : scale 1000 and roughness 1,00;
4/ We perform a dents effects (effects menu > distort > dents) with the following parameters : scale 15 and amount 50;
5/ We add noise (effects menu > noise > add noise) with the following parameters : intensity 50, color saturation 0 and coverage 100;
6/ We perform a motion blur (effects menu > blurs > motion blur) with the following parameters : angle 0° and distance 5;
7/ We duplicate the layer (CTRL + Shift + D);
8/ We apply an outline effect (effects menu > stylize > outline) on the new layer;
9/ We edit layer properties and switch it to multiply mode;
10/ We merge the layers (CTRL + M);
11/ We perform a drop shadow effect with the following parameters : offset X at 5, offset Y at 5 and blur radius at 5.