Quote Originally Posted by kb3lms View Post
Thanks for the responses everyone. So it would appear that our efforts compare fairly well with the products of the early 20th century. If only I could coat as well as they did then!
Film speeds were

Super XX 200ASA
Plus X 125ASA
Verichrome 125ASA

As far as know (I've been wrong more than once) those are the speeds GIVEN by film companies, but yes there was a change in ASA speed at one point. Basically they would rather you OVER expose, than under, and I think that means at one point 100 speed was really 200 speed at today's standards. But I don't know when that cutoff was, and there were different versions of at least plus-x and verichrome so they may have really been 400 and 250 speeds at today's standards.

That's my understanding.


~Stone | Sent w/ iPhone using Tapatalk