I am using Dura-lar film matte surface as my substrate. It has just enough tooth to hold the graphite. It is difficult to get rich dark marks with pencils, however you can use other media to achieve that. This leads into why I love using this substrate. You can use multiple wet and dry media on the surface, like oils, gesso, and acrylics. I have not tried pastels, but I don’t see why it wouldn’t work. I look forward to experiment more with this surface and sharing my results.