The Kodak 3A used 122 film. 122 film is the "postcard" film format. I think the nominal dimensions are 3.25in x 5.5in

Could a lens from one of these old kodaks work alright with a 4x5 camera?

I have everything I need for 4x5 photography, just not the lens. And Kodak 3A cameras are fairly cheap. Busted ones are even cheaper.

Would focussing at infinity cause any problems?

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