I am trying to identify this typeface (the letterforms in "Isopan" and "Feinkorn Film," etc) used on 1930s-era packaging of Agfa camera films. It has similar characteristics to a few Antiqua typefaces of the 1910s through 1930s, including Bravoura and Lipsia-Antiqua, however the lower case 'g,' uppercase 'F,' and lower case 's' are different and distinctive.
I'm fairly certain it would be a typeface from a German (or Austrian) foundry and likely to have been introduced between 1900 and 1930.
Any suggestions?