查看完整版本: 刚看到的一篇爱好者折射镜溯源文章，还不错

刚看到的一篇爱好者折射镜溯源文章，还不错

作者[i]Dave Novoselsky，[/i]一位年过六旬的器材老烧友。
a+j$~&s7Eyc 这个文章从早期欧美的长焦普消到德国蔡司APQ都写了，算是前两部分，现在还差一个日本篇。讨论的回帖里说用40寸的叶凯士折射镜看，虽然色差很大，却能看到河外星系里面的球状星团:funk:+D2~.]#a#E1m$v:if-r1n
另外，zeiss工厂的最后把关的资深光学技师直接在测试台上用大锤砸镜子也是第一次听说:Q/~P5mso

U]4A:{l/A{ While there is quite a lot of information available about today'samateur refractors and the current market, there is not a lot availableabout where this all started and the 'roots' of what we can now buy anddebate the merits of so vigorously here and at other locations on theNet. Much of what I will say here will be of limited interest to someor may seem the rambling of a senile and opinionated curmudgeon. Thelatter may be accurate, but here goes, and if it is not of interest,let me know, and I will stop.-EGS Q&S

3n(c'?{l9\&{$V There have 'always' (meaning since the Industrial Revolution madescientific instruments readily available outside of the confines ofacademia and a few wealthy dilettantes)been some amateur telescopes forsale. The birth of the hobby, however, began in the late 1800s whensome English and Continental makers (small, mostly family businesses)offered reflectors and refractors, usually in the 2 to 3" range for thelatter for sale with simple tripod mounts and a selection of eyepieces.In the United States, Alvan Clark & Sons, who began buildingrefractors for Universities and governmental agencies (including a 26"instrument at the Naval Observatory and the ultimate refractor, the 40"Yerkes refractor located at Lake Geneva, Wisconsin) offered a line of'standard' amateur refractors mostly in the 2.4 to 4" range but withavailable models up to 8". The company sold these with mounts, tripods,and piers as well as eyepieces.
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The Clark standard models were simple, albeit nicely figureddoublet achromats. Color was simply a inherent issue with these scopesand there successors which can still be found in this basic formattoday, the classic 'Christmas Scope' with simple optics, poor buildquality, and the single most common cause of a rapid loss of interestin the hobby by the kid who gets one or the parent who tries to dealwith using them. The Clark tradition of building a good but simpleachro for the US amateur market continued after the Second World War inthe US with companies such as Unitron (Clark closed its doors soonafter the war ended) and, again, primarily in the 2.4 to 3.5" aperturerange, with simple mounts and eyepieces not much advanced over theClark products of the turn of the prior century. p0TW-D1K
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Today, these refractors (as opposed to Christmas junk) can bepurchased by a frugal amateur from a number of companies who marketthem as now built, with modern coatings and better mechanical features,hopefully, from several sources in mainland China.
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The real successors of Alvan Clark & Son are the handful ofsmall, and sometimes one man operations such as D&G and Parallax.They offer the traditional, long focal length achromats, in sizes up toand sometimes a bit larger than an 8"aperture. These very long, butrelatively light OTAs are the last vestiges of the traditional high endacrho market. With modern coatings (my newly-acquired Parallax 7.1"F/15has a Royce Optics doublet with modern coatings on all foursurfaces)and hand figured to the most current optical specifications,these scopes produce great images with only a hint of color -- often'cured' to a great extent by filters such as the Baader Semi-apo.
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However, and as much as I like my Parallax and my friend loves his8" D&G, these scopes are the end of an evolutionary line nowbecoming extinct. While there will also be a place for simple acrhos,given price advantages for the beginner or amateur on a strict budget,or those who want a large aperture at a reasonable price, they are nolonger in the mainstream. For the source of the current 'state of theart' we need to go back to Germany and just after WWI in time.
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:p4?`A{_8l$l (By the way of a digression, achros always have color issues by thebasic fact of the design. The D&G and Parallax big acrhos, evenwith VERY long fls, still will show some color at high power or oncertain very bright targets. Now if you REALLY want to see color, Ihave been lucky enough to be allowed to view through some of thehistoric large aperture scopes built by Alvan Clark. The views I hadthrough the EP of the Yerkes refractor were literally breathtaking. Butcolor? You betcha. A whole lot and not subtle either. The 24" Lowellrefractor and the 26" at the Naval Observatory are also spectacular.Incredible views. (Remember that increase in light gathering byincrease in the diameter of the optic is not as it appears. Theincrease of two or three inchs of diameter yields a multiple of surfacearea, the real measure of light gathering ability. Now scale up theview of the largest 'available' refractor of 6" to the optic of a 24 o440" refractor and you get the idea.) But color? Oh yeah, and somethingno filter will remove.) 6]6p*}b+ZHy&G(^4I3M
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The German optic industry has a long, and well-justified reputation forskill, innovation, and perfection of design and production of carefullycrafted high end products. I have an interest in rangefinder cameras aswell as other hobbies. In cameras and camera lenses, the names Leciaand Zeiss stand out above most others. Interestingly enough, andgermane to the present discussion, those companies were the inspirationfor and 'copied' and then matched and sometimes 'bettered' by severalJapanese optic firms, including Canon, Nikon, Pentax and others. And,as with Zeiss, several of these Japanese companies also developedsuperb optics intended for amateur astronomers, following the lead ofZeiss.*ir.` q4fJ@P
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Inthe years after WWI, Zeiss introduced a growing line of amateur otpics,lens cells and complete telescopes, for the amateur market. Originallyhigh end achros, very much in the Clark mode, using its own research inthe development of optics for the scientific and government markets,Zeiss introduced the first APOs to be commercially available in any'production series.' Today, these can still be found, albeit rarely andat a VERY high price, as the ZEISS APQ series.\ V3Mz3w8A$W

:}m({6r DC:o The APQs wereflourite triplets built to the very highest standards. (Zeiss builtsuperb doublets as well.) Using what was then the most advancedscientific testing methods, each optic was rigorously tested beforerelease.
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Fc'k'H|u _.TZ Indeed, QC was maintained at the very highest level.Tom Back told me a story he had heard from a long-time Zeiss employeethat each APQ was given its final test by a senior optician who tookevery scope out to check its performance on the skies. If the optic didnot meet his standards, regardless of preliminary test reports, itwould rejected in the most emphatic manner as he would put it on abench and smash it with a hammer! Zeiss would not take the chance ofhaving a single sub-standard optic with its name on it leave thefactory. (I have heard this same story from others, so it would seem tobe true.)P:jr
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The APQ series was capped by the 150. This largest ofall the Zeiss apos, if it appears on the market today, commands ahealthy five figure price tag and even then rarely lasts on the marketfor more than a day. I looked through one at a star party. It lived upto its billing, although today's high end refractors will outperform it.
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TheAPQ is the ancestor of all of todays APOs. Several current designerstrained in the Zeiss "school" with Roland at AP building upon thisheritage, both as to design and emphasis on the highest possiblestandards of optic performance and rigid quality control. These sameprinciples found there way into our next section, the early JapaneseAPOs.

等有实力的时候，一定要弄一个Zeiss的APQ看看。。。

文中说APQ很对得起它五位数美刀的价格，但是同时也提到APQ被很多后来推出的知名APO所超过。我觉得它的意义主要还是在收藏。

还是当历史研究吧bbbb28

fancysky兄，能不能搞个原创翻译？看这洋文晕啊！bbbb45

好，等高桥专篇发表以后，收齐了后我统一大致来试着翻下一下主要内容。

不错 看过了 算是学习了一些 :handshake