50 f1.2 Focus and Optical Cement Issue Question

[Mojo]

Thinking about acquiring a Canon 50mm f1.2 rangefinder lens for my Leica and possibly a GXR. I was told by a well-known US camera service tech that he had quite a few Canon rangefinders for repair with optical cement problem. I have not seen any discussion in the forums on this issue. Has anyone heard about this.

Is it difficult to focus the 1.2 wide open? I plan to acquire a Ricoh GXR; will focus peaking help?

Thanks.

 

[Vickko]

Yes, I heard about the potential of Canon lenses developing doublet separation, due to their age, and happening around now.

I can't remember where or what I was reading.

But I didn't put much to the story, as I thought it was hard to believe that any one generation of gear would be prone to failure under the same failure mode.

Mind you, many of the Canon RF lenses are now decades old, but I don't hear of similar failures in other brands like Nikon RF or Leica RF of the same age.

Sure, there are stories of particular lenses that are more susceptible to failure than others (e..g, soft coatings on some early Leica lenses, separation on Nikon 3.5cm f1.8, Nikon 5cm f1.1, Schneideritis).

But not an entire family, e.g all Canon lenses with doublets being susceptible to optical cement failure.

 

[ferider]

Don't think separation is more of a problem for the Canon 50/1.2 than for other lenses of this age.

However: in contrast to other lenses of this period, many canon LTM lenses - and in particular the 50/1.2 - have problems in the coating on the surfaces before and after the aperture due to hazing that then is impossible to clean without destroying the coating.

Roland.

 

[Vickko]

Hmm, maybe that is what I heard, Roland.

Would you know why? Just the combination of grease (whale?) used and type of coating?

Other companies used something else and they stood up better?

Leica internal coating on older lenses was notoriously soft.

Oh, I also remember a Leitz 90mm f2.8 lens that was notorious for haze, maybe something due to an internal adhesive they used.

 

[Mackinaw]

Haze is very common with this lens (on the element surface directly behind the aperture) but it can be easily cleaned. I've gotten so good at it I can literally take apart the lens, clean, and reassemble in about ten minutes. Problem is the haze always comes back.

I've also heard about "staining" that is occasionally found on/in this lens. I believe you find this in the rear element group (which is cemented together). This may be what the repair tech is referring too.

Jim B.

 

[ferider]

Hmm, maybe that is what I heard, Roland.

Would you know why? Just the combination of grease (whale?) used and type of coating?

Other companies used something else and they stood up better?

Leica internal coating on older lenses was notoriously soft.

Oh, I also remember a Leitz 90mm f2.8 lens that was notorious for haze, maybe something due to an internal adhesive they used.

Don't know why, Vick. Only that I've seen it with 50/1.2, 50/1.8, 100/3.5 (both 34mm and 40mm copies) and 50/1.5. None of the 50/1.4 copies that I have had, had that problem. The haze didn't surprise me, many Leica lenses have that too, and are typically easy to clean without coating damage (I've cleaned both collapsible and DR Summicrons, for instance). And old Leica coating feels softer than Canon LTM coating, typically. But somehow the haze in the Canon LTM lenses was "eating" the surfaces close to the aperture.

Roland.

 

[Mackinaw]

......And old Leica coating feels softer than Canon LTM coating, typically. But somehow the haze in the Canon LTM lenses was "eating" the surfaces close to the aperture.

Roland.

Year's back, when I was on LUG (Leica Users Group), one of the list historians said that, because Zeiss patented the vacuum application of coatings (like what is used today), Leica lenses of the 1950's had coatings that were liquid-based and literally dripped on. Don't know if that's true or not, but, if so, may explain their softness.

Jim B.

 

[Roger Hicks]

. . . Don't know if that's true or not. . .

Dear Jim,

To the best of my knowledge, most assuredly not.

Cheers.

R.

 

[ottluuk]

It's a very cool lens, especially for the price you can get one for. Just try to get a clean one from a decent seller. Watch out for the original hood - they are expensive and difficult to find separately.

I haven't had much trouble focussing at large apertures but then again, I mostly shoot static things and I'm rarely in a hurry to do so. The focus ring is large, well damped and has about 180 degrees of travel which definitely helps. BUT the lens has significant curvature of field which can cause some funky stuff when the subject is way off center.

You probably know that already but the 50/1.2 should be considered mostly for its character/rendering and if you are looking for raw performance, the f/1.4 version is a better choice. Personally, I really love the results I've been getting from my f/1.2 but it is obviously not uniformly well-behaved like modern f/1.4 designs. But in light of the ongoing bokeh craze, you'll have no hard time selling it if you decide you don't like it.

 

[Mojo]

Thanks for the comments. The tech told me the optical cement deterioration problem is mainly with the f1.2 starting a year and half ago.

Yes, I am interested in the 1.2 for how it renders out of focus. It will be a character lens only for wide open. I have a Nikon f2 ltm for slower speeds.

 

[Brian Legge]

That seems suspicious to me. Lenses have such different histories, some treated worse than others. I would expect to have seen a bunch of failures in the more abused 1/4 of lenses if there was a systemic problem.

The RFF community is so quick to jump on weaknesses of lenses or lines of lenses that if there was a lifetime issue I would expect a much higher percentage of the lenses to have had failures by now. 🙂

 

[Pioneer]

I cannot comment on lens separation other than to say that I understand it most commonly occurs in lenses which use a certain cement. I do know that I have owned two Zeiss Ikon lenses for my Contaflex that had separation problems. I had one of mine repaired so it can be done if you want, but it takes time and can be expensive.

I love fast lenses and own several. They are all difficult to focus wide open and close up for the simple reason that the area that is truly in focus is very, very narrow. It does take practice. I find it easier to get corret focus with my ZI and my M3. On the M9 I use a magnifier but it is still hit and miss for me. Maybe I am just sloppier with digital cause I can chimp.

Of course at infinity I have no problem at all. 🙂

In my personal experience it does not seem to be any better with autofocus. My Canon 1Ds Mk II does not hit 100% of the time with my fast 50 or 85 either. Especially when I am trying to take pictures of my black cat. 🙂

 

[goamules]

I've owned a few 1.2s and handled a lot more. Never seen any separation on any of them. And the idea that all would begin to fail....right...NOW! is comical. Someone is pulling your leg or just likes spinning a tall tale.

Do cemented lenses have separation? Yes, especially if they get too hot, like in a car, or sitting in the blazing sun often. But I commonly shoot 160 year old lenses (yes, I wrote that correctly) that have no separation, or a tiny bit on the edge that doesn't matter. The F1.2 Canon is a cult lens in my experience, and the prices always showed that. Buyers aren't going through dozens trying to find the golden "good" one.

I agree with you Brian, the internet forums always have someone that starts spinning a worry factor on any lens, usually starting with "...but you've got to get a good one..." They imply that only a fraction of the Summars, or Sumarits, or .95 Canon, or Nikkor 1.4, or J-3 are any good. The rest have horrible problems. I just don't buy it.

 

[Frontman]

I buy and sell Canon LTM lenses with some regularity, and though many are prone to haze, of the 50 or so that I have had, only one had a problem with separation. From the looks of it, whoever had had the lens previously had tried polishing off the internal coating to get rid of a haze problem, and got the glass hot enough that the cement softened.

If your tech has seen more Canon LTM lenses than I have, I would be surprised. I have had half a dozen 50/1.2 lenses, and though most had haze to an extent, or chips in the glass caused by slipped tools, none have had any separation.

 

[Mojo]

Thanks all for your comments. I was quite surprised that the tech warned me to stay away from the 1.2 because as many of you have mentioned if high optical cement failures were the case, the net would have been ablazed with posts indicating so. I have 1.4 lenses but none give the creaming out of focus of the Canon 1.2. I will search for a good sample and hopefully I can do the lens justice. I am still wary of the DOF. Thanks again.

 

[Monochrom]

Hi, the 50 1.2 is a great little lens.

The images it produces are very beautiful even at 1.2 is very special and stopping down to 5.6 is superb.

Wide open has tons of spherical aberration, but in the center is still sharp enough.

NEver had problems abot separation and had many RF canon lenses.

with a .72 VF is enough in my case to nail focus.

But take into consideration you will get focus shift with out any doubt.

My sample was a 2.8 optimzed lens, but after a while i changed that to 1.2, and when i sold it i returned to the original setting wich is the correct one for fast lenses.

Try one you won´t be sorry!

🙂

 

[aoresteen]

Here's a tip for you 50 1.2 users. As mentioned the correct Canon shade is expensive and hard to find. While I have one, I use an Olympus OM shade for their 55mm f/1.2. It's 57mm and slips on just right.

With an M3 no issues with viewfinder cut out.

On my M3-MOT:

 

[Mojo]

I am so delighted by the generous support by the forum members. Now that the optical cement problem is a non-issue, I have a few questions that need clarification.

1. Is there any optical difference between version 1 and version 2 and coating difference between early and late serial numbers? Is there a preference?

2. I plan to use the lens mainly wide open on my M2. I read that if the lens is optimized for the intended camera, focusing will be enhanced. Any comments?

3. I do not have a digital but am thinking about the Ricoh GXR with the M module, even though it may be dated, as a starter kit for value. How much will focus peaking help in low light? I read that this feature is not always dead-on. Any tricks on low light focusing in general?

Thanks