Summicron's 50mm rigid cap diameter

[timetraveller]

Hi,

I want to purchase a vintage cap for my summicron 50mm rigid, but i'm not sure of the diameter I should order: 39mm or 42mm???

The actual diameter of the lens is 39, but I don't know if the diameter of the cap refers to the measure of the lens or to the measure of the cap itself...any ideas???

Thank you

[luigi bertolotti]

Usually, the lens cap of the old Summicron 50 (and other lenses too) was referred to as "42 mm diameter" that is the measure of the front barrel , 39 is the measure of the filter thread, usually not used for caps (even if I have an old Leitz Canada front cap that screws into the 39 filter thread... an oddity...).

The old 42 mm Leitz lens cap is not difficult to find : the classical is silver with "Leica" embossed (unpainted) and a fine velvet ring inside, to have the correct grip without damaging the lens: it's a detail that can be worn in a used item... but is of exceptional quality and, if you find a nice one, can be sure you will be able to cap-decap thousands of times without problems...

[peter_n]

Another alternative is to buy a new Leica front lens cap for the recently discontinued Elmar-M 50mm/f2.8. I have that front cap on my desk here along with a cap from a recently acquired v.1 pre-ASPH Summicron 35mm/f2. The older cap is less matte in finish than the new cap and to be honest, the new cap matches the finish of the rigid 50mm perfectly whereas the older cap looks shiny.

I've tried this new Elmar-M cap on both a 50mm rigid and a 50mm DR I also happen to have here. It fits perfectly. I recommend this as a solution because the scripting on the front of the cap is identical to the old one, the new cap is a perfect match to the finish on the rigid, and it is still beautifully made and you will get all the advantages enumerated by Luigi above. The Leica part nr. for the silver cap is 14321. If you live in the United States B&H in New York have them in stock:

Leica | Lens Hood Cap for 50mm 2.8 M | 14321 | B&H Photo Video

[luigi bertolotti]

Originally Posted by peter_n

Another alternative is to buy a new Leica front lens cap for the recently discontinued Elmar-M 50mm/f2.8. I have that front cap on my desk here along with a cap from a recently acquired v.1 pre-ASPH Summicron 35mm/f2. The older cap is less matte in finish than the new cap and to be honest, the new cap matches the finish of the rigid 50mm perfectly whereas the older cap looks shiny.

I've tried this new Elmar-M cap on both a 50mm rigid and a 50mm DR I also happen to have here. It fits perfectly. I recommend this as a solution because the scripting on the front of the cap is identical to the old one, the new cap is a perfect match to the finish on the rigid, and it is still beautifully made and you will get all the advantages enumerated by Luigi above. The Leica part nr. for the silver cap is 14321. If you live in the United States B&H in New York have them in stock:

Leica | Lens Hood Cap for 50mm 2.8 M | 14321 | B&H Photo Video

Good alternative... but if your Summicron is chrome, a black cap is terrible....

[peter_n]

Not sure I understand your comment Luigi. The cap I describe and link to above is silver chrome. Leica also makes the cap in black, part nr. 14285. B&H also have that cap in stock although they have mislabeled it as plastic but it is anodized metal.