WECC member Nick Bedford published a YouTube video showing the process he produced in Photoshop and Silver Efex Pro to simulate the classic Kodak TRI-X 400 film stock. Original published in July 2017, his original article has been updated as well with the video and some other changes.
This is the best simulation of Kodak TRI-X 400 black and white film I've made so far. You can try it as well!
You'll need Photoshop and DxO Silver Efex Pro from the Nik Collection, but it works best with Lightroom and VSCO Film 01's Tri-X 400 preset.