一只苏联产物镜。上面的标志符号比较难认。

收藏的过程也是学习的过程。不然我不可能知道相衬物镜还分正负。

而且国内的厂家存档的文字资料较少，时间长了就搞不清了。
下图是一个国产的用在倒置显微镜上的相衬物镜。正相衬，长工作距离，平场。

清朝时的孤品银元是无价之宝，那这只1972年产的孤品镜头呢？ 我不能确定它是否真是孤品，请手头有同样镜头的网友也亮亮宝。

谢谢朋友帮顶。

谢谢D兄解惑。我想国产物镜的标志应该是汉语拼音，所以没明白那个S的意思。物镜的种类繁多，各个厂家的标注方法也不同。有时真挺难猜啊。

好贴 帮顶下   

-XC 的意思是负相衬，这是个相衬物镜。还有一种是+XC，正相衬。

SP一般是Semi-Plan的意思，半平场。场曲介于平场物镜和普通的消色差物镜之间。

最近收的国产物镜。不太明白上面标志的意思。-XC 前面的负号是什么意思？SP 是什么物镜？

请知道的大侠赐教。

这台国产镜做工精良啊。

这帖是我的自留地。片子比较另类啊。

这个我也有一台，XPA-I型。呵呵

K兄可以开光机博物馆啦

蔡司和苏联产的工业和军用光学仪器。

两台不常见的苏联产旁轴相机。Fed 3 1a 款，Zorki-2, 和一只很少见的国产35毫米电影摄影镜头。608厂产 长城20mm F2.

早期核工业部267厂生产的偏光显微镜。

目前为止仅此一台的苏联产红字莫5折叠机。

一款少见的英国产偏光显微镜。

一款南京生产的售价只有上海牌1/4左右的紫金山牌手表当年很受欢迎，如今成了收藏者们喜欢的，难得的藏品。

还是早期新中国生产的轻工产品，上海牌手表，1970年代一个普通工人要不吃不喝2-3个月才能买一块。

真挺像。※※牌的，我猜？

K老师，我这市场门口经常竖这玩意，您看像不像CARL ZEISS生产的某款全球顶尖光学产品这东西又高又粗还冒烟，价值不菲啊

本帖最后由 小牛角 于 2015-7-3 16:18 编辑

另一种有趣的便携式显微镜。

结构图。

网上见到的便携式偏光显微镜。

国产16毫米电影摄影机。

European watchmakers are competing for lucrative slices of the China market, but not everyone in the world's fastest-growing economy is interested in a Chopard or a Blancpain. One small clique of collectors prefers to concentrate on homegrown brands — and they don't mean upscale makes. Their obsession is for mechanical watches produced by communist factories from the 1950s to the 1970s, and stems from a mixture of historical curiosity and opportunism. It's an area of collecting that has been barely explored, with no price barriers to entry.

Hong Kong native Joel Chan is one of the pioneers. When not scouring the curio and antique shops of Shanghai, the 38-year-old collector frequents online forums such as those at Watchuseek.com to satisfy his time-consuming but affordable craving. The website's Chinese Mechanical Watches forum is a learned gathering where Chan and his fellow aficionados politely compare and praise each other's recent discoveries, discuss dial typography and intricate case engravings, and generally provide encouragement to other members of their growing band. Chan also writes a blog at micmicmor.blogspot.com, and generously — in fact surprisingly, given the secretive nature of many collectors — shares locations of the dusty Shanghai outlets where he adds to his collection of more than 700 Chinese watches. If you want to see what the fuss is about, pay a visit to Mr. Rong, whose quaint and rarely troubled store is at 378 Changle Road in the city's Xuhui district. Or try Mr. Xie's dealership at 425 Fang Bang Zhong Road.

Chan admits that a love of his country partly spurred his original interest in old Chinese timepieces. A chance meeting with a Japanese collector left him perturbed by the thought that overseas enthusiasts were snapping up China's horological history. "I was jealous of them," he admits, and immediately set about studying the subject. Today, novice collectors regularly approach Chan with their questions, and a book is in the pipeline.

The earliest, state-produced watches in China, Chan says, came from the Shanghai Watch Factory, founded in 1955 — six years after the declaration of the People's Republic. Rare handmade 1956 Shanghai prototypes of the Heping (meaning "Peace" and Dong Fang Hong (or "East is Red" models are the favorites in Chan's extensive collection. They were based on a classic Swiss movement, and Chan acquired them from private collectors for a few hundred dollars each.

Of the first 100 or so pieces produced by Shanghai, only 12 passed the modest quality standards, which required the watches to neither gain nor lose more than 120 seconds a day. But these unreliable prototypes, Chan explains, provided the basis for the mass-produced A581 — launched in July 1958 and adorning many Chinese wrists until its discontinuation in 1967. Millions of A581s were made, which means that today they are relatively easy to pick up in Shanghai curio stores from about $15 (variations in dial color and casing style will affect the price). Chan is also a fan of the A623, launched in 1963 and the first Shanghai watch with a calendar function. The A623 was not available to the general public but only provided to high-ranking government and military officials — a fact that lead to its nickname of "the minister watch." The very first piece made was strapped upon the wrist of China's then Premier Zhou Enlai, who wore it until his death in 1976. The trusty timepiece is now on display at the National Museum of China at Beijing's Tiananmen Square. In 1964 a special edition of the A623 was released to commemorate the successful testing of China's first nuclear device.

Chan snapped up his A623 in an online auction for just under $150 — underscoring the fact that early communist-era Chinese mechanical watches are within the financial reach of almost anyone. "Even many rare models can still be found for [around] $75," Chan says. To be sure, some pieces occasionally fetch impressive sums (a 1955 Shanghai Watch sold at auction for over $15,700 in 1996), but for the moment no one is talking about the investment value — only the pleasure of getting your hands on a quaint piece of revolutionary history.

Time magazine 文章的内容.:-)
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2007年美国‘时代周刊’的文章。介绍了当时建立不久的WUS的中国机械表论坛。

很少见的国产16毫米快速电影摄影机。

眼光锐利！ 我收了一台Zeiss Winkel 的GFL.许多部件都是通用的。

原国营二六七厂生产的另外一种偏光显微镜XPS-III