Patrick,
If you wish, I will send you a specific formula and procedure for a blue-sensitive emulsion based on commercial silane treated PVA. I am currently waiting for a delivery of silver nitrate and have not made an emulsion since September. I have had other things I had to do. If you are interested in ortho or panchro emulsions, I can send info on that too. But I strongly recommend doing a simple blue sensitive emulsion first. BTW- Bostick and Sullivan now carry Kuraray R1100 silane funtional PVA.
Bill