Summicron 50/2 L39 LTM question

[jusxusfanatic]

Summicron 50/2 L39 LTM question

Yep, I got it 🙂 anyways, when "extending" the lens, the turn to lock it is a bit stiff, by stiff I mean it's smooth, but needs a little bit of force, same with the focusing ring, smooth but need a little bit of force. Is it supposed to be like that? I don't think so..

 

[Robert Lai]

Lens lock is supposed to require some force, as you don't want it to collapse accidentally while in use. The focusing should be smooth and easy. Your lens may need relubrication of the focus helical.

Look though the lens with a light source on the opposite side (cell phone flashlight will do). If you see haze, then the lens should be professionally serviced. Otherwise, you will join the chorus that claims that this lens is "low contrast".

Congratulations on getting a true classic lens.

 

[jusxusfanatic]

Lens lock is supposed to require some force, as you don't want it to collapse accidentally while in use. The focusing should be smooth and easy. Your lens may need relubrication of the focus helical.

Look though the lens with a light source on the opposite side (cell phone flashlight will do). If you see haze, then the lens should be professionally serviced. Otherwise, you will join the chorus that claims that this lens is "low contrast".

Congratulations on getting a true classic lens.

Sounds good, thanks! 😀

 

[jusxusfanatic]

I think my lens needs relubrication as I need a little bit or force to turn it, just a teeny bit.

No haze tho 🙂

 

[Ko.Fe.]

Put it in refrigerator to cool it down. If focus stiffness will increase too much, it is time to re-lube it.

 

[jusxusfanatic]

Put it in refrigerator to cool it down. If focus stiffness will increase too much, it is time to re-lube it.

Are you serious about putting it in a refrigerator? Other people told me to do that too

Btw, can I re-lube the helical without taking apart the lens? Thanks 😀

 

[Robert Lai]

Make sure that you have a UV filter to protect that front glass!

Also, I use only canned air to blow off dust from the glass. If there is a fingerprint, use a Q-tip (ear cleaning cotton bud), and some lens cleaning fluid, and very very gently clean it.

 

[jusxusfanatic]

Make sure that you have a UV filter to protect that front glass!

Also, I use only canned air to blow off dust from the glass. If there is a fingerprint, use a Q-tip (ear cleaning cotton bud), and some lens cleaning fluid, and very very gently clean it.

Of course!

 

[splitimageview]

Btw, can I re-lube the helical without taking apart the lens? Thanks 😀

No. The old grease should be removed, and new lube applied; the only way to do this is to take the lens apart.

 

[jusxusfanatic]

No. The old grease should be removed, and new lube applied; the only way to do this is to take the lens apart.

Alright then, thanks 🙂

 

[Ko.Fe.]

Are you serious about putting it in a refrigerator? Other people told me to do that too

Btw, can I re-lube the helical without taking apart the lens? Thanks 😀

Not it the fridge, but into refrigerator where temperature is low, but above freezing. It is exactly the same as using lens outside in (mild) winter time.
If lens has too old lube, it will became much more stiff under cold temperature.

But some of us are using Leicas under freezing temperatures every winter🙂

-21 C. by Kostya Fedot, on Flickr

You can't re-lube without taking both parts of focusing helicoid apart, cleaning each part by toothbrush and gasoline like liquid, before applying new lube. Some RF lenses are very easy to re-lube, some ain't so.

Here is famous youtube repair channel, I used his video couple of times.
How to re-lube collapsible Cron. https://www.youtube.com/watch?v=bORzSzjyakM

 

[jusxusfanatic]

Now I get it, thanks!

Btw, is the turn smoooth like the elmar 50/3.5?

 

[jusxusfanatic]

More replies please!

 

[David Hughes]

Hi,

The light seals in the lens that run around the long lens barrel are felt and sometimes get loose and twisted and make it stiff. So they have to be sorted out and reglued.

The focussing ring sounds like the usual problem and you've the answer to it although I'd prefer an expert to do it all and check the rest of the performance. Lots can go wrong gradually and never be noticed...

Regards, David

 

[splitimageview]

Felt light seals? The Summicron collapsible has these?

 

[jusxusfanatic]

Yea I was wondering aabout that!

 

[David Hughes]

Felt light seals? The Summicron collapsible has these?

Well, you don't really know because I've only seen one and it could have been a home made repair...

Regards, David

 

[Dralowid]

I can't remember whether this lens has the felt light seals but I think it might. If it does a tiny bit of oil on the barrel will ease them and make the action smooth, if it doesn't I doubt it would do much harm, it can't migrate to glass from there.

What does go wrong is the spring loaded ball that runs in a channel on the barrel. With misuse this can run out of the its channel and make all sorts of scorings on the barrel, jam etc.

All actions should be smooth and easy. To tighten up the 'lock' you can very slightly bend the bayonets for the barrel. It should be obvious.

 

[davidnewtonguitars]

Pretty sure it's in there David, right under that conical section on the Elmar, seen in a cross-section cutaway picture (which I can't seem to find now). I mean, the tube has to slide on something.

Well, you don't really know because I've only seen one and it could have been a home made repair...

Regards, David

 

[jusxusfanatic]

Alright thanks 🙂

Gonna go and ask someone to help me check if the focusing on the cron collapsable is that "tight"