Well, ever since I wrote my column called "The 50mm Lens and Metaphysical Doubt" — the point of which is that lens choice isn't as crucial to pictures as some photographers might wish to believe — I've been hearing from a bunch of enthusiastic photographers who want to know about my own professed "favorite" 50mm lens, the Pentax Super-Multi-Coated Takumar.

Takumars are M42 screwmount lenses. They will fit on Spotmatics — SP, SPII, SPF, ES, and ESII primarily. The early 52mm-filter-thread 50/1.4, called the "K" lens, was a different but very similar design in a bayonet mount. The SMCP-M lens is similar but the design was changed somewhat.

If you're interested in finding out more about the arcana of different Pentax lenses, the best place to ask further questions is on the PDML, the Pentax-Discuss Mailing List, which is found at www_pdml_net.

Basically, there's not a whole lot to choose between the lineage of Pentax fast 50s. I think you're safe with virtually any version of the classic Pentax 50mm f/1.4. They are, in chronological order, and starting with the lenses for the Spotmatic:

[b]Early 8-element Super-Takumar (M42 screwmount) with one radioactive (!) element...if you let one of these sit on a piece of Polaroid film for a few hours, then pull the Polaroid, you'll see a faint halo exposed by the rare-earth element itself! It's very difficult to tell the scarce 8-element lens apart from the much more common (and slightly better) 7-element Super-Takumar — the trick is that the focusing ring is just slightly different in width.[/b][b]The construction quality of the classic 7-element Super-Takumar was superb — not quite as good as the Zeiss lenses of the day but better than the Zeiss/Contax lenses available now.[/b][b]The Super-Takumar — note the cemented concave and convex surfaces between the fourth and fifth elements. Modern lensmakers shave costs by making these cemented surfaces flat.
7-element Super-Takumar (M42 screwmount).

Super-Multi-Coated Takumar (M42 screwmount) (note that this is "not" equivalent to "SMC" — this version, which still has a metal focusing ring, has the words spelled out on the lens barrel).

SMC-Takumar — last of the M2 screwmount versions, this one came with the SPF and had a rubberized focusing ring.

SMC-Pentax, a.k.a. the "K" lens, first of the bayonet mounts, 52mm filter size — Pentax took Nikon's lead in fiilter size for the first and last time with the K lenses.[/b][b]The cross-section of the K and M lenses.
SMCP-M lens, "compact" version for the M cameras, 49mm filter size.

SMCP-A lens, had the contacts for program operation, cheapest and worst-feeling of the manual-focus barrels but rumored to be the sharpest.

SMCP-F lens, first version of the autofocus lens.

SMCP-FA lens, current autofocus version.[/b]

Everything from the "K" lens onward will fit on any K-mount camera, from the KX and K2 to the ZX-5n and MZ-S, and including the K-1000 and all the M-series and A-series cameras. There are no significant incompatibility issues apart from the program-mode contacts present in the A-series onwards, and of course you need both an autofocus camera and and autofocus lens to get autofocus capability.

There are minor, subtle differences over the years. The Super-Tak and S.-M.-C. Tak were from back when Pentax was competing with Zeiss, and Pentax allegedly produced every fast normal lens it made at a loss — the quality level is very high and reflects a lot of hand-building and hand-inspection. The "K" lens is the same optical formula in a K-mount. The M lens is reputedly the least sharp, but it's still very nice (it's the lens I currently use). The A lens is supposed to be the sharpest of all, except that some people think the F lens is the sharpest — and the current FA lens has most if not all of the good qualities of its many predecessors.

All these lenses are classic Planar designs, as are more or less every fast 50mm except for the Leica M lens, which is an idiosyncratic design unique to Leica; but where most makers have economized by making the surfaces between the fourth and fifth elements flat, Pentax has always stuck with the original design and used cemented spherical surfaces there. Aside from being more expensive to manufacture, this results in a lens that is slightly less sharp at infinity in the plane of focus, but that has better off-axis aberration correction and thus, better bokeh or blur.

The rest of the visual differences can be accounted for by subtle differences in coating processes over the years, as well as the changing fashions in mechanical lens barrel construction. Early Pentax multicoating was superior to every company's except Zeiss's, which equalled it, and even today Pentax has better lens coatings than, say, Nikon or Olympus. The early Takumar designs were gorgeously built — they're just about the smoothest-focusing lenses ever made, Leica not excepted. This excellent mechanical construction and "feel" lasted through the SMCP-M lens, which handles marvelously (for me, the commonplace SMCP-M lens is just about ideal in terms of size, weight, feel, and handling). The "A" lens with its typical, tacky 1970s design style is pretty cheaply put together by comparison, and of course the autofocus lenses suffer from the same problems as virtually all AF lenses except Pentax's own Limiteds, in that they're mostly plastic and feel relatively cheap.

As for Pentax's Limited 43mm normal, it's an entirely different kettle of fish. It doesn't resemble the 50mm much at all. It's a very high-resolution lens with very low flare. A different look altogether.

If anyone reading this were actually want to get one of these lenses, I'd simply suggest buying whatever camera most suits your needs, and going with the vintage of lens that suits the camera. The MX and SMCP-M lens is a nifty combination; the MZ-S and current FA lens is up-to-date in its capabilities; the K2 or KX with the "K" lens is a typical dinosaur of its (bygone) era, from when SLRs resembled big metal bricks; and you can have a bit of fun by getting on eBay and acquiring an antique Pentax with one of the screwmount Taks for not very much money. Of these, I think the ESII and Super-Multi-Coated Takumar is a sweet combination, and of course the all-time classic is an SP Spotmatic with a Super-Takumar. It takes some hunting to find one in really good condition (although they were such durable cameras that it's quite unusual to find one that doesn't look pretty darned good for its age).

Remember, too, that obsessing about lenses just isn't necessary. They all take great pictures. But if it's fun for you, then do it! Messing around with cameras and lenses is safe, pleasant, legal, and harms no one. All things considered, it doesn't rank very high on the scale of silly vices.

[2002-11-25 23:56 补充如下]

writer:Mike Johnston

[2002-11-25 23:56 补充如下]

This is copyright infringement!

感谢天狼大侠。
不过看来我有些地方弄错了，汗颜

不揣冒昧，瞎翻了几句。
我是个菜鸟，要是翻的有出入，还请P家各位DX指出。
最后一点......
===============================================
　　　If anyone reading this were actually want to get one of these lenses, I'd
　　　simply suggest buying whatever camera most suits your needs, and going
　　　with the vintage of lens that suits the camera. The MX and SMCP-M lens is
　　　a nifty combination; the MZ-S and current FA lens is up-to-date in its
　　　capabilities; the K2 or KX with the "K" lens is a typical dinosaur of its
　　　(bygone) era, from when SLRs resembled big metal bricks; and you can have
　　　a bit of fun by getting on eBay and acquiring an antique Pentax with one
　　　of the screwmount Taks for not very much money. Of these, I think the
　　　ESII and Super-Multi-Coated Takumar is a sweet combination, and of course
　　　the all-time classic is an SP Spotmatic with a Super-Takumar. It takes
　　　some hunting to find one in really good condition (although they were
　　　such durable cameras that it's quite unusual to find one that doesn't
　　　look pretty darned good for its age).
　
　如果谁看到这些想要得到这些镜头的话，我只能简单的建议你买最适合你需要的，并且相机的
　型号也要注意匹配。MX和SMCP-M的镜头极其般配；MZ-S和FA的镜头也日渐合拍；K2 或者 KX带
　“K”口的镜头在是典型的早年的恐龙/*什么意思？？*/，那时开始，SLR的相机就像金属大砖　头；你也能在EBAY上富有趣味的拍到一个很便宜的PENTAX抓口  /* 不懂,是不是罗口? */　的老机器。还有，我认为ESII和S.M.C Takumar在一起也是郎才女貌，亲怜蜜爱的小两口。当　然，任何时期的都是经典的是一架SP 点侧的机器加Super-Takumar的头。要找到成色好的得好　好寻摸寻摸（尽管这些东西都很耐用，找到一架相对于机龄来说狠好/*狠狠地好*/的机器仍然
　是望外之喜。）

　　　Remember, too, that obsessing about lenses just isn't necessary. They all
　　　take great pictures. But if it's fun for you, then do it! Messing around
　　　with cameras and lenses is safe, pleasant, legal, and harms no one. All
　　　things considered, it doesn't rank very high on the scale of silly vices.

　同时要记住，沉迷困惑于镜头没有必要。所有的这些镜头都能照出极好的照片。但是如果它们
　对你来说很有乐趣，那就只管放开手脚去玩！四周乱七杂八的都是相机和镜头安全、有趣、合
　法并且不伤害任何人。一切都无伤大雅，在无聊的癖好里，玩这个排名还不太高.

[长歌 编辑于 2002-11-26 15:03 ]

不揣冒昧，瞎翻了几句。
我是个菜鸟，要是翻的有出入，还请P家各位DX指出。
不过这个贴子狠毒阿，，理由如下：...
===========================================
　　　There are minor, subtle differences over the years. The Super-Tak and S.-
　　　M.-C. Tak were from back when Pentax was competing with Zeiss, and Pentax
　　　allegedly produced every fast normal lens it made at a loss — the 　　　　
　　　quality level is very high and reflects a lot of hand-building and hand-
　　　inspection. The "K" lens is the same optical formula in a K-mount. The M
　　　lens is reputedly the least sharp, but it's still very nice (it's the 　
　　　lens I currently use). The A lens is supposed to be the sharpest of all,
　　　except that some people think the F lens is the sharpest — and the
　　　current FA lens has most if not all of the good qualities of its many
　　　predecessors.

这么多年来又有了一些细微的变化。当PENTAX和Zeiss竞争时，Super-Tak以及S.-M.-C. Tak的镜头逐渐淡出了，如前所述，连PENTAX出产的每个普通镜头都有点不计工本——工艺质量非常高、大量反映手工制造的细节。"K"卡口系列的镜头在K-卡口上都能得到同样的光学质量。M系列的镜头据说是 [整个P族镜头中]最不锐利的，但是表现仍然很好（实际上正是我自己用的镜头）。A系列的镜头被认为是所有当中最锐利一系，尽管有些人认为F系的是最锐利的——而现产的FA系列的镜头就算不是全部，也拥有绝大部分它们前辈的上佳质量。

　　　All these lenses are classic Planar designs, as are more or less every
　　　fast 50mm except for the Leica M lens, which is an idiosyncratic design
　　　unique to Leica; but where most makers have economized by making the
　　　surfaces between the fourth and fifth elements flat, Pentax has always
　　　stuck with the original design and used cemented spherical surfaces
　　　there. Aside from being more expensive to manufacture, this results in a
　　　lens that is slightly less sharp at infinity in the plane of focus, but
　　　that has better off-axis aberration correction and thus, better bokeh or
　　　blur.
所有的这些镜头都是经典的Planar结构，就像现今绝大多数的50mm镜头一样，除了莱卡——采用一种莱卡独有的设计；但是在绝大多数厂商在研磨第4和第5块镜片表面采取较经济的平面做法时，PENTAX仍然矢志不渝的坚持传统设计，并且采取粘合的球面表面。除了加工成本更高一些外，这样加工出来的镜头在无穷远的焦平面上锐利程度有细微的下降，但是拥有更好的轴外失真校正/* 原文为off-axis aberration correction，不知道翻对没有*/，并且有更好的bokeh或者说焦外虚像。

　　　The rest of the visual differences can be accounted for by subtle
　　　differences in coating processes over the years, as well as the changing
　　　fashions in mechanical lens barrel construction. Early Pentax
　　　multicoating was superior to every company's except Zeiss's, which
　　　equalled it, and even today Pentax has better lens coatings than, say,
　　　Nikon or Olympus. The early Takumar designs were gorgeously built —
　　　they're just about the smoothest-focusing lenses ever made, Leica not
　　　excepted. This excellent mechanical construction and "feel" lasted
　　　through the SMCP-M lens, which handles marvelously (for me, the
　　　commonplace SMCP-M lens is just about ideal in terms of size, weight,
　　　feel, and handling). The "A" lens with its typical, tacky 1970s design
　　　style is pretty cheaply put together by comparison, and of course the
　　　autofocus lenses suffer from the same problems as virtually all AF lenses
　　　except Pentax's own Limiteds, in that they're mostly plastic and feel
　　　relatively cheap.
就如同机械镜头筒制造的风格随时间变化一样，成像效果也可以认为随着镜头表面的处理工艺的变化而有微妙的差异。早期的PENTAX多重镀膜在其他所有的厂商之上，除了蔡斯的能与之一拼，就算是现在，PENTAX的镜头表面处理也比，如果直说的话，比尼康和奥林巴斯强。早期的Takumar设计是辉煌的——几乎是所有的（莱卡也算在里面）出产的镜头中对焦最柔顺的。这一杰出的机械设计和手感一直持续到SMCP-M系列的镜头中——它们的手感真是不可思议（对我来说，普通的SMCP-M系的镜头简直就是大小、重量、感觉和操作性的完美结合）。“A”系列的镜头是典型的70年代俗气的外观风格，比较起来塑料感太强，给人感觉是相当便宜的大路货。（这种问题实际上PENTAX所有的自动对焦的镜头都有，PENTAX的 LE 镜除外。）

　　　As for Pentax's Limited 43mm normal, it's an entirely different kettle of
　　　fish. It doesn't resemble the 50mm much at all. It's a very high-
　　　resolution lens with very low flare. A different look altogether.
对于PENTAX的43mm LE 标镜来说，简直就是焕然一新，完全不象50mm的镜头的表现。眩光很小，解象力极高，外观自成一格。

[长歌 编辑于 2002-11-26 14:29 ]

先上翻译的第一段：

自从我写专栏“50mm镜头及理论上的怀疑”（该文中指出镜头的选择对照片本身来说并不象有些摄影师坚信的那么至关紧要）以来，我从许多热情的摄影师那里听到希望了解我公开声称自己喜爱的50mm镜头，Pentax Super-Multi-Coated Takumar。
Takumar是M42罗口镜头。它们安装在最初的Spotmatic系列机器上——SP、SPII、SPF、ES and ESII。早期的52mm滤镜螺纹的50/1.4，被称为“K”镜头，是一个不尽相同但拥有非常类似设计的卡口镜头。SMCP-M镜头也比较类但设计稍微有些改变。
如果你有兴趣去找出更多的关于不同PENTAX镜头的秘密，最好的询问深入问题的地方就是PDML，Pentax-Discuss Mailing List，你会在www_pdml_net里找到它。
基本上，在PENTAX短暂的50年的系统里面选择，并没有一个纯粹的划分。我认为你无论选择PENTAX哪个版本经典的50/1.4镜头都是非常可靠的。按年月日次序的话，它们是由用于Spotmatic开始的：
[b]早期的8片Super-Takumar（M42罗口）有一片放射性镜片，如果你把他们放在一块宝利来（或者是偏光）胶片，然后拉动宝利来，你会在它的后组镜片上看到一圈模糊的光晕。很难说明8片镜头与7片Super-Takumar有什么不同除了8片的更加普及（以及稍好一点）——诀窍是其只有调焦环行程有少许不同。
经典的7片Super-Takumar的结构是非常好的——虽然不完全比得上Zeiss镜头的时代，但比现在的Zeiss/Contax兼容镜头要好一些。
Super-Takumar——注意第4片凹面镜和第5片凸面镜是粘合起来的，现代的镜头制造者进行薄片切削的价值正是在保证粘合表面的平坦。
Super-Multi-Coated Takumar（M42罗口）（注意这是不相同于“SMC”——仍然拥有金属对焦环的这一版本在镜桶上有单词的完整拼写）
SMC Takumar——最后一个版本的罗口镜头，这个镜头是随SPF机身一起出现并拥有橡胶对焦环。
SMC-Pentax，也叫做K镜头，第一个卡口镜头， 52mm的滤镜口径——PENTAX在K镜头上第一次也是最后一次引入NIKON的滤镜口径。
有代表性的PENTAX “K”及“M”镜头。
SMCP-M镜头，为M系列机器制造的紧凑版本，49mm滤镜口径。
SMCP-A镜头，拥有程序触点，最便宜以及手动调焦桶手感最差，但是传闻更加锐利。
SMCP-F镜头，第一版的自动镜头。
SMCP-FA镜头，现在的自动镜头版本。[/b]

自K镜头以来的所有镜头都能安装在任何一步K卡口机身上，从KX和K2到ZX-5N和MZ-S，以及包括K-1000和所有的M版和A版机器。自程序触点出现在A版本机身上以来，没有重大的不兼容出现，当然你需要一个自动机身搭配自动镜头来获得自动聚焦的能力。

原作者因该为Mike Johnston，没错吧。请问为何不交待？

This is copyright infringement!

这可以给无忌带来麻烦。