When I first looked at this lens, I could not believe that it's almost 80 years old. It's beautifully made of brass. Everything still works perfectly except the focusing is very stiff, due to the grease dried up.
No doubt a very special lens, this Dallmeyer creates very unique pictures with a swirling background, similar to the 75mm Carl Zeiss Jena Biotar. Very small lens but image circle covers the Panasonic G1 sensor without problems. With its hood on, there is a slight vignetting. No vignetting at all with the hood off.
The Image quality? Well, by modern standards, this lens can be classified as having horrible edges. In fact, even when stopped way down, the edge is not sharp. But, people do not buy this lens for the sharp edges, they actually buy it because it does not have sharp edges.
The center of the lens is very very sharp, even wide open. You would not believe such excellent optical quality lens was produced some 80 years ago.