OlProfBear- Yes, yes, I do now remember the nomenclature 4R and 3R. I agree that the 4"x6" print size seems to have come about in the 80s.
Bill Mitchell- I was not aware of the FLEIN printers! This would confirm my belief of the existance of a smaller standard print size than 3.5" x 5.5" This would possibly account for why I've heard of 6 x 9cm sized prints from 35mm in photo collections found in Europe. Do you have a FLEIN printer?
Ole- 7 x 10cm, a size I was not familiar with! It would seem that prints ranging in size from 6 x 9cm to 7 x 10cm, would look better and provide more continuity when displayed with and along side the contact prints that were so popular with roll film cameras of the era.
Paul Howell- Great find from 1946. That kind of confirms what I thought that a smaller size was the "Standard"
To all; I have just been told of a Argus brand printer from 1938 that was called the "Argus Electromatic Speed printer model EFA" for making a "Standard" size print of 2 3/4" x 4 1/4" or converted to metric 6.9cm x 10.5cm. This matches up with the smaller sizes you folks mentioned.
It would seem as though these smaller size prints with less than a 3x enlargement when exposed through a Eljy, Chema, Argus A or venerable Leitz with the older emulsions, with out a light meter, focused by guess and developed in home brewed soup would be wonderful to look at. At first this size seems small, but when you consider the number of contact prints from the 6x9cm folders such as Voigtlander and Zeiss Ikontas that many enjoy so much, I think these little jewell size prints from 35mm may really be quite pretty with the sperical abberation (Bokeh) found in the simple lenses. I shall have to give it a try with several older simple cameras.
Sam Hotton