gregory peck

Opening sequence typeface for To Kill a Mockingbird


Hi everyone,
I've been quite perplexed over the last few days trying to figure out what this particular typeface is.
It appears on the opening sequence of Gregory Peck's 1962 film "To Kill a Mockingbird." The typography struck me as beautifully modern but I am yet to determine what it is set in. I think there's another forum on this topic that suggested Akzidenz Grotesk as being a likely candidate, however, they didn't arrive at any solid conclusions and I'm adamant that someone out there knows! Such is my curiosity that I've created an outlined vector file showing the differences that are most apparent to me.

Thanks for your help!