I have a few of the Masuyama eyepieces from the 1980's. These were discontinued after being manufactured just a few years. Masuyama started production again recently and this is what is said about the new version. "Masuyama eyepieces are back in production and updated with modern glass and multi-coating technology."
I haven't had a chance to compare any of the new versions with the old. Some of the newer ones are different in terms of AFOV but the 60mm version is 46 degrees which is the same as the old version. I doubt there are too many who have compared these 2, but I am wondering in what way the glass might is different. Is modern glass better? In what ways? Or is this all marketing? I know coatings have developed and improved but how has the glass changed?