Filter size/thread for Elmar 9cm f/4 Ernst Leitz Wetzlar

Does anyone know the filter thread/size for the above lens? I've looked around and couldn't find anything definitive.

Thanks.

Mine has the same size filter as 5cm Summicron, 3.5 cm Summaron, and 135 Tele Elmar. Can't recall 39mm?

Mine has the same size as the 5cm Summar which is smaller than 39mm.

Mine has the same size as the 5cm Summar which is smaller than 39mm.

My kit was Dad's, and ex the 135 was bought in Germany - guessing, around '54. Yours is apparently different - before I wrote I made certain filters were interchangeable on my lenses. Possibly one of the Leica Forums can help.

Ditto - mine was also my Dad's. The Elmar's serial number dates to 1933 or '34.

All four of the versions listed on the all photo lenses database have m39 filters

I included the macro model (two versions include Leica M variants & screw threaded variants)

Hopefully the pictures will help you identify which if any of those included is your model.

All four of the versions listed on the all photo lenses database have m39 filters

I included the macro model (two versions include Leica M variants & screw threaded variants)

Hopefully the pictures will help you identify which if any of those included is your model.

 

Thanks, unfortunately all these are too "new". I have an M-mount 9cm and yes it takes 39mm filters but as you can see in the attached photos, the M39 screw mount lens (black) takes a smaller (~33mm-ish ) filter than the M-mount 9 cm (silver).

After more digging it appears to be 34mm

Are you going to try a step up ring? Just about certain they are still out there.

Yes that's clearly smaller than M39!

Tmo me it looks like it's 33mm between the inner parts of the threads which would be what you expect from a M34 x0.5 thread. Metric threads are designated according to the measurement across the outside of the male threads, the diameter between the inner edges of the female threads will be about twice the pitch smaller than this (actually slightly smaller to allow some movement between threads 0.2mm leeway is typical for the threads I've measured).

 

M34x0.5 is one of many threads around this size that have been used in photography. I know of M32.5x0.5 threads on some enlarging lens filters (as well as Copal 0 mounting threads), m33 threads of unknown pitch used on early Industar 50-2 models...

This region is also one where pitches are not standardized in the way they are on larger filters pitches of 0.5 & 0.75 are used seemingly at random between 25.5mm & 43mm with both being used on different m37.5 filter threads. Looking at my notes on optical screw threads I've found an amazing 29 different threads between 25mm & 40mm diameter, and the chances are quite high there are several I've not come across!

 

It's not easy checking the pitch of very fine threads like these especially in female form. If you get a metric pitch gauge you can supposedly use it to judge the pitch but I find visual comparison with filters of known pitch often works out easier. filter threads between 43mm & 77mm are nearly always 0.75 pitch, if it looks finer than this it will be 0.5 pitch (as long as it's a metric thread).

NB the Leica M39 screw mount is a strange mixture of metric & imperial despite being very close to 1mm pitch its M39 but at 26tpi (tracks per inch). Similar odd combinations might be seen in early Lietz filter threads :eek:

 

Perhaps not a solution you'd want to use on a Leica lens but I've heard of options like using sticky foam to pad out a smaller stepping ring so as to fit unusual threads. I have a couple of old sprung filter holders (one sold as 'Handcross' but the other having no identification) that could be used to attach filters - again I might be reluctant to fit them to a Leica lens & risk scratching the paintwork.

 

The ideal solution might have been the smallest size 'Revoring' adjustable stepping ring, I backed on kick starter a year ago, but it seems so far it's only the larger sizes that are being made so far. So much for the November 2020 dispatch...

 

 

Edit - Typical taken far too long typing & you've got the answer already!

Edited March 22, 2021 by petrochemist

Are you going to try a step up ring? Just about certain they are still out there.

Exactly. That’s the plan.

Mine has a 34 mm filter thread. It is probably a 1952 copy. The "Walz" UV filter fits nicely with same barrel width, so the cap doesn't drop off.

Don't know about the screw-in size, but the clamp-on filters for them are of the "A36" type, same as for the 5cm Elmar/Hektor/Summar and wider LTM lenses. And for the 135mm Hektor as well.

My 1951 is also a 34mm thread. FIKUS hood fits over it.

Edited March 27, 2021 by luis triguez

My 50mm Summar takes an A36 clamp-on filter.

BTW, that is a terrific lens

So here's the skinny: 34mm to 43mm step up ring fits perfectly and as an added benefit fits a DCR-150 Raynox close-up lens just for fun. Maximum mag of the 9cm Elmar with the Raynox is about 0.5:1. Shot is handheld, ISO 200, f/18, Nikon Z7, squirrel vertebra.