Plastic "King of Bokeh"

<p>Too bad Leica decided to use a poor choice of materials on the crowned "King of Bokeh" 35mm M lens.<br /> <strong>Critical</strong> parts that are made of polycarbonate. (Plastic)</p>

<ol>

<li>The aperture / lens <strong>holding</strong> unit</li>

<li>The aperture "click" detent bar</li>

<li>The aperture blades actuator ring</li>

</ol>

<p>It's been mentioned before, but I never found any images of what items actually are plastic. (Now provided)</p>

<p>Issues that have been experienced with this particular batch of Canadian made, fourth version of the 35 Summicron M series is<strong>:</strong> Installation / removal of the lens from the camera by use of the lens shade or aperture ring, may cause the index TDC mark to be off and generally a loose now problematic lens group unit. Attempts at tightening this now loose front group, will cause the plastic threads to either fail or advance in it's thread travel.</p>

<p>Adhesive is required to seize up the group into it's alignment. Knowing this, care should be used to mount / remove the lens from the camera body by grasping the focus tab and/or DOF ring. Techs should always be careful when tightening any of the set screws into or against any of these plastic parts.</p>

<p>If you <strong>can't</strong> get with the "care-program", there exists a delicate method of drilling a strategically placed access hole near the focus tab and then tapping a tiny set screw <strong>to</strong> the aperture / lens <strong>holding</strong> unit.</p><div></div>

<p>A priori, I would have expected that the choice of "plastic" by Leitz would have validated and endorsed the use of "plastic" rather than being taken as a "poor choice of materials."</p>

<p>Is this the lens I see eBay for a cool BIN price of $2,228.00?</p>

<p>Heck, I can get you a plastic 50mm f/1.8 for about $100. :)</p>

<p>Gus,</p>

<p>Interesting, and thanks for posting.</p>

<p>As an aside, have you ever considered posting on rangefinderforum.com as well as on here?</p>

<p>I'm sure that your knowledge and expertise would be very welcome there as well as here. If you think you might like to do so, why not have a word with the owner of the site, Stephen Gandy?</p>

<p>John</p>

<p> </p>

<p>A good bokeh is often described as being "plastic". Those details seem to lack a certain harshness...</p>

<p>Gus,<br>

Do the Silver V4 lenses share all the plastic parts?</p>

<p>Those parts look relatively straightforward to machine (out of the appropriate metals) in a CNC environment. Hmmm.....</p>

<p>What about the clear stuff in the middle of the lens, the part photons go through? Is that glass or plastic?</p>

Polycarbonate is a particular type of plastic known for being quite strong and resistant. My old Nikon F80 was made of polycarbonate... which made it light enough to carry about, as I later discovered when I bought my F100 (which was NOT made of polycarbonate). I learned not to diss it. As far as plastics go, this is one tough customer.

<p>Looks like the primary flaw was expecting waaaaay too much out the fine threads on the barrel section that hold it into the mount. Definitely a misuse of the material. I think parts of the focusing mounts in the Pentax-M and Pentax-A lenses are polycarbonate, and you don't see complaints about them being fragile. (They have a very nice feel.)<br>

You would think the aperture blade actuator ring would be strong enough. Of course, if you're torquing the lens off the mount by the external aperture ring, you could put a lot of load on the pegs into that inner ring, and blast the holes in it. I suppose the detent bar can be a victim of the same abuse.<br>

Of course, in 1979 Leica was in the middle of the M5 marketing debacle, with the Leica CL eating away at M-series profits. So economies like those plastic parts were probably seen as a lifesaver to the company. (This was the time when many camera companies were floundering on the rocks of electronics.)<br>

Yeah, someone could probably setup a closet industry making aluminum replacement parts. Might need to consider if the thermal expansion and contraction of the aluminum alloy is too different from the polycarbonate, might need to have slightly differing internal diameters. You would also need to be savvy about any dimension changes that anodizing the aluminum would cost. But, yeah, in an order of 100 parts, that might be a reasonably priced part.<br>

Of course, it would be nice if Leica were to make that part...</p>

 

Hi Gus. Does this apply to the German version IV Summicron too?

<p>Thanks to Gus for sharing his knowledge freely with any other repair folks reading this. I emailed him while shopping for a Summaron 35/3/5, asking about CLA. He volunteered that I might want the screw mount because it has the same optics as the M-mount and is smaller.<br>

I bought one, and it arrived in good condition, but when a lens needs work, I'll contact Gus.<br>

Incidentally, my chance to use a Summarit 35/2.5 cured me of desire for a Type 4 or Type 1 Summicron.</p>

<p> </p>

<p>Why would the German version be any different? Basically, I don't care if it's made out of cardboard, it's a great lens.</p>

<p>Harley & Richard, my experience says no. But, if you look at the front of the lens and see a <strong>grey</strong> colored ring around the name bezel, then you have a plastic holding unit.</p>

<p>John, I totally agree, but the aperture blades actuator ring is even weaker than you thought, there's only one pin driving it !</p>

<p>Good to hear Charlie, thanks.</p><div></div>

<p>My Summicron V4 has a metal lens holding unit but plastic actuator ring. I didn't disassemble it far enough to see if the click detent bar is plastic or not. When changing the aperture one can easily feel how flimsy the whole thing is...</p>

<p>A gorgeous lens, but you definitely need to be gentle on it!</p>

<p>Gus, great post, as usual. Thanks for sharing!</p>

<p>K.</p><div></div>

Yours is German, Koray. My current worry is my tabbed 50 Summicron made in Canada. The aperture stops feel very

sloppy lately. Before this I thought it might just be stiff lubricant and grime. Now I'm not so sure. Time for a service

anyway.

<p>Richard, no mine is Canadian, too. At least that's what it says on its side! :-) The German ones have distance scales in newer Leica font.</p>

<p>K.</p>

Thanks Koray. Interesting. A lot of the Canadian lenses have LEITZ CANADA on the lens front, leaving no room for

the serial number which is then on the lens barrel.

<p>I have had the 4th gen. 35 Summicron at least three times over the last 15 years -- never a mechanical problem. But I must say that the differences among all the versions were real but minimal IMHO. 4th not worth the difference -- plastic, metal or wood!</p>

<p>I don't purchase Leica lenses with anything other than metal construction for major components anymore despite the, in my opinion, miniscule optical improvements that come after the significant incorporation of plastic in subsequent versions of the same lens. </p>

<p>The exceptions are <a href="00S9kR">bargain lenses I come across</a> occasionally such as an Elmarit-M 1:2.8/21mm I bought used for a song. It rocked back and forth about 1mm or more somewhere along the barrel, so I sent it to Sherry Krauter for a CLA. Sherry didn't want to touch it because some of the components were factory glued together. She sent it to Leica USA, who sent it to Solms. It returned after three months looking cosmetically much worse than when I sent it, but at a highly discounted service price and free shipping. At least it works fine.</p>

<p> </p>

<p>My problem with the whole thing is not so much what the thing is made of, but that they now want to sell us pot metal, plastic and cardboard, etc., at the price of machined steel or brass. They made their reputation with a certain level of quality vs. price, and now want to slip substandard products off as the real deal. <br>

Washing machines and dryers are so full of plastic now that the Maytag Man has to be called back from his deathbed. Welcome to the 21st Century.<br>

Great post, Gus!</p>

 

<p>Thanks Frank.<br>

Robert, check out the construction of an inexpensive Canon screw mount lens. The aperture detent bar as pictured here, is chrome plated metal !</p>

<p>The plastic one in the version IV Summicron pictured on page one, actually had a hairline crack forming in it. Pretty common for certain plastics to discolor & become brittle as age sets in. (Originally a white somewhat translucent color) </p><div></div>

<p>So you would rather have a Canon SM over a 4th Sum because it's all metal? This is making a lot of sense.</p>

<p>Gus, that's a real eye opener!</p>

<p>It makes me wonder what's really inside a Leica MP. Maybe I shouldn't be so keen on eventually getting one. A very well known and respected Leica personality told me in confidence, that in their opinion, the Leica M4 was the last of the superbly well built Leica M bodies. That was before the Leica MP came on the market. I wonder how it compares in materials and build quality with the Leica M4 and previous M bodies? I don't want to pay the money being asked for a Leica MP if some key interior plastic component is destined to disintegrate or otherwise lose its structural integrity, even if I'm not around to witness it. </p>

<p>Barry...</p>

<blockquote>

<p>"<strong>Too bad</strong> Leica decided to use a poor choice of materials"</p>

</blockquote>

<p>I think we all understand the reality with the economics of that era and the subsequent experimentation that took place. Maybe Leica had to succumb to the pressure to "cheapen" their build quality by using the new plastics of the day? I don't know. Yet, faced with that "Fork in the road", time has shown that they went left when they should have gone right.</p>

<p>I can't help but to lament over the fact that there exists out there, <strong>very pricey & sought after</strong> "M" gems, with hidden time bombs <em>in them</em> that also have the lofty branding of Leica <em>on them</em>...</p>

<p>I got my very pricey 4th version Summ 35 for about 700 USD a few years ago. I don't think the other lenses, especially the outrageously priced new lenses are using plastic the same way if at all. So why anyone is paying 2500 dollars for one of these is a mystery. I did see one for 2500 from Hong Kong because of this thread and a silver one for 3500. I think these are people selling the Leica name to people that don't know any better. The 4th version is sought after because it's a great lens and they were always much less expensive then the asph versions that replaced them.</p>