Palaeoboy
Joel Matherson
When I started using 40mm lenses on Rangefinders I at first accepted the general statement that 40mm Summicrons are Single Coated and the CLE Rokkors are Multi-coated. A statement still repeated even now. Without doubt the CLE Rokkor is Multi-coated, but what I couldnt figure out was why the Summicron didnt seem to flare any more or less in identical situations. With no real theory or solution, I just kept on accepting the general coating statement of the 2 lenses.
Then one day I acquired an Elmar-C lens and its coatings were completely different in colour to that of my 40mm Summicron. It was more orange and the same as an Compact TE 90 I had as well, a lens that was supposed to be Multi-Coated. That was strange but possibly just that the 40-C's were coated one way and the 90-C's another. But it got me thinking perhaps I should watch out for either a 40 or 90 C lenses with coatings in reverse to the ones I first purchased. And then I found one! I have attached a photo for you side by side. One clearly has a deep purple blue coating the other quite orange. Leica is known not to announce certain changes so is this a case that through its production life was the 40mm Summicron given Multi-Coatings? There is certainly clear evidence of a coating change but could this just be a case of change in single coatings? One further thing I noticed was that the purple blue coated lenses were given phillips head screws for their mounts and the orange coated ones have been given regular screws for their mounts. None of the CL Rokkors I have observed have had the orange coating that I have seen on many Leica lenses of the period including R lenses.
So my fellow forum sleuths what do you think? I have a theory but there is one thing that doesnt fit but I will mention that later once I hear more of your thoughts?
PS This is just meant as a fun little puzzle that I have been pondering for a couple of years now just thought others may enjoy having a stab at it too given the number of 40mm enthusiasts that have been posting recently.
Then one day I acquired an Elmar-C lens and its coatings were completely different in colour to that of my 40mm Summicron. It was more orange and the same as an Compact TE 90 I had as well, a lens that was supposed to be Multi-Coated. That was strange but possibly just that the 40-C's were coated one way and the 90-C's another. But it got me thinking perhaps I should watch out for either a 40 or 90 C lenses with coatings in reverse to the ones I first purchased. And then I found one! I have attached a photo for you side by side. One clearly has a deep purple blue coating the other quite orange. Leica is known not to announce certain changes so is this a case that through its production life was the 40mm Summicron given Multi-Coatings? There is certainly clear evidence of a coating change but could this just be a case of change in single coatings? One further thing I noticed was that the purple blue coated lenses were given phillips head screws for their mounts and the orange coated ones have been given regular screws for their mounts. None of the CL Rokkors I have observed have had the orange coating that I have seen on many Leica lenses of the period including R lenses.
So my fellow forum sleuths what do you think? I have a theory but there is one thing that doesnt fit but I will mention that later once I hear more of your thoughts?
PS This is just meant as a fun little puzzle that I have been pondering for a couple of years now just thought others may enjoy having a stab at it too given the number of 40mm enthusiasts that have been posting recently.