著：Alan MacRobert 译：Shea天文望远镜器材评测和交流论坛+ ~" k6 ?2 V# }) e# t4 P
一旦你拥有了一架望远镜，你期望从它那儿得到些什么呢？或多或少都会有些出乎你的意料。
, ?) _- N0 e( s国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材业余天文学家的最大乐趣之一是向他人展示星空的壮美。当人们第一次通过望远镜看到月亮和土星时所发出的惊叹声是对那些望远镜拥有者的最大回报。自然地，你会将望远镜对准地平线上最壮观的天体。有时你会有一种向人们展示更经典的天体的冲动——那些若隐若现、勉强可见的目标——“让人们了解什么是真正的天文学”。但反映却不那么令人鼓舞，甚至当人们被告知他们正在看的是一颗回归的彗星或是一个离我们4000万光年远的星系时，也是如此。天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪+ t. g; B) {9 x
事实上，在业余级设备所能看到的数千个天体中，大多数一点也不壮观。任何有望远镜的人，期望得到那些具有视觉冲击的画面都是徒劳的，他们已经走入了误区。
5 G2 c0 W, v1 I+ L天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪天文学的魅力不在于此，它更有深一层的含义。目视观测意味着去寻找那些极其暗弱、微小、难以找到的天体，或者是三者皆而有之的天体。任务越是艰巨，然而，成功之后的回报越是大。兴奋与喜悦总蕴藏在寻找和看到那些离我们极其遥远的天体之中——并且从中获得技巧和知识，就像一个业余天文学家。
' M8 ?9 E7 F" S& i% v+ q/ N& o* p( O1 ]国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材许多人买望远镜，就好像它是一部彩电，希望它们自己能放出图像。可是望远镜更像一架钢琴，它的回报总是与你在它身上花的时间成正比的。然而，学习用好一架望远镜远比学会一种乐器要来的简单。如果你坚持不懈并且仔细实践在下文中提到的一些技术，相信不久之后你就会精于此道了。www.astroview.com.cn- v1 Y$ w+ k2 ?4 L! z
了解你的设备天文家园欢迎您！$ X2 I+ \9 N$ Z9 y0 a6 z
很自然，每个人都会在白天第一次使用他的新望远镜。这是你熟悉望远镜的机会，它的运转、指向、调焦、不同的目镜和放大倍数，之后你就可以在晚上干任何事了。天文望远镜器材评测和交流论坛, e1 c1 P& X0 a. A6 Z* G9 f
寻星镜。几乎每台望远镜在其一侧都有寻星镜来帮助你瞄准目标。你需要一个寻星镜，因为主望远镜的视场太小——只能看到一小片天空——你无法精确的辨认出他正指向哪儿。
; v+ h3 V- W( `# z4 C放大倍数越高，视场越小。例如，在50倍的放大倍率下，你所能看到的天区大小仅相当于在离你一个手臂远的地方你手指甲所能覆盖的范围。另一方面，通过一个8倍的寻星镜，你能看到的天区则相当于一个高尔夫球在一个手臂远的地方所能覆盖的区域。国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材3 S" T. u) M. Q2 |
这已足够大来瞄准一些目标了，并且使它们出现在寻星镜的视场中。一旦它们出现在视场中了，把它们调至十字叉丝的中央。如果用主镜来完成这些工作，其艰巨程度是难以想象的。
7 u/ d* {. C3 L3 r# G% f天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪最重要的事先做：你需要调节寻星镜支架的螺丝使它与主望远镜平行。在白天，使用低倍目镜将主镜对准至少数百米远的某个物体（但不要对准太阳！不要将望远镜对准太阳，否则你会使自己致盲）。远处的树顶是理想的选择。不要介意它是上下颠倒的。
, D1 p% K  M& M; W" b: n, W天文望远镜器材评测和交流论坛现在通过寻星镜观察，看到树顶了？它是否在十字叉丝的中央？调整寻星镜支架上的螺丝，直到十字叉丝的交叉点与目标重合。现在检查一下主镜，确定它没有转动。然后换一个高倍目镜，重复前面的步骤直到寻星镜的指向以被精确的调整并且锁定。
! q% z4 x. [: [9 d# Mwww.astroview.com.cn你会问，为什么树顶是上下颠倒的或是指向其他古怪的方向？答案是这是一架天文望远镜,毕竟在宇宙中没有上下之分。因此，视场的方向性无关紧要。把影像调回正确的指向需要额外的光学器件，这会增加费用和设备的复杂度并且可能会稍稍降低图像的质量。因此，“正像”透镜组织用于地面上的望远镜，它们只用于观察地面上的东西。天文望远镜器材评测和交流论坛7 ?6 q7 S# {' z) u8 K- d
接下来则是支架。在《如何选择望远镜》一文中提到，望远镜支架有两种基本类型：赤道式和地平式。www.astroview.com.cn2 _7 I  {8 _- _( _
赤道式的支架仅允许望远镜沿着天空中的南北方向和东西方向运动。地平式的则是上下、左右运动。地平式支架有简单的优点。赤道式的则非常有用，但你需要花时间来适应。
- H4 V. M  p$ F2 ~% O( [天文家园欢迎您！赤道式支架。如果这是你买的那种，找到它的极轴。在户外，架起你的望远镜使极轴指向北极星。现在望远镜就能绕着这个轴跟踪天体在天球上的运动了。1 D8 d0 ~" x( _. O! X. H. g
将你的望远镜从东面的地平线扫过天空然后指向西边的地平线方向，想象一下这就是晚上恒星运动的轨迹。一开始赤道式支架的运动看起来很笨拙而且不可预测。但是记住，无论望远镜指向哪儿，它始终朝向或远离北极星（天空中的南北方向）运动，以及垂直于此方向的方向（天空中的东西方向）上运动。这需要你在白天花时间练习和适应。国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材  J- |) f4 \: Q9 ]# q9 g6 A
观测技巧天文家园欢迎您！4 l, l! D. W: T7 e) m( R. a. ^1 f/ ]
天文学的挑战是我们必须观察离我们极为遥远的天体。在地球上当你想看清楚某样东西，你的本能是靠近它，然后看个真切。但是，对于遥远的恒星和星系，我们只能呆在我们所在的地方。因此，从望远镜天文学诞生至今，观测的技巧始终是将你的眼睛发挥到最大限度的艺术。
6 ~% A4 e2 Z5 y& Z4 t5 p1 A% r观测提示。当你通过望远镜观察时，请仔细调焦。一个好的观测者总是乐于花时间在调焦上，尽量使星象变得最尖锐。许多人发现保持两只眼睛都睁着比较好，因为闭起一只眼睛会使另一只工作的眼睛疲劳。你可以用手盖住你的一只眼睛。
! n) x$ W1 @4 ^# `+ p' I天文望远镜器材评测和交流论坛不要期望一下子就能看到天体的细节，看一眼所能看到的总是比后来的少。这是事实，不管你观测的是一个仅能从天空背景中区分出来的星系，或是月面上的细节，或是一颗明亮的行星。
8 D$ S& P& K# u# T! T: c需要花时间才能看到细节的一大原因是地球不稳定的大气。由于在我们上方微弱但总是存在的热气流，使星像在高倍放大下总是显得闪烁和沸腾。这种闪烁的剧烈程度——被称为大气视宁度——每晚甚至是每分钟都在变。
) H% A$ x; z# H当你观察一个“颤抖”的天体，不可预料的细节会在大气稳定的瞬间闪现，此时星像会变得尖锐，但却在你意识到它之前就消失了。有经验观测着的会记住这些美妙的时刻并且忘掉其他的部分。大气视宁度对于用高倍率观测明亮的天体尤为重要，但它也可以影响暗弱的天体。
7 B) _7 J- F3 \, b0 e" bwww.astroview.com.cn然而，需要花时间才能看到细节的主要原因不是大气的影响而是眼睛和意识。从视场中发现暗弱的天体意味着学习新的视觉技巧，这需要聚精会神的努力。
2 H  {! A( d# u. t国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材你会发现眼睛对一些极难观测的天体的成像非常的慢。当一个细节被看到并固定下来时，你会想没有东西会在被看到了。但是几分钟后，另一个细节出现了，接着是另一个。天文家园欢迎您！9 k  H: a, W$ i" u. B
为了使你确信这一点，用肉眼观察一片天空并且努力去发现暗弱的恒星。一些恒星会被立即看到，另一些则要花上几分钟。当没有恒星出现时，大多数人决定放弃了，但是请再坚持一会儿。可能在先前认为空无一物的区域出现了星点。过一会儿，你至少能多看半个星等了。
. \  r0 w% e  D天文家园欢迎您！火星是这一效应的经典例子。当初学者第一次用小望远镜观测火星时，火星可能是天空中最令人失望的天体。它仅仅是个小而无细节的橙色绒球。初学者走到一边让一个有经验的火星观测这来看。片刻的沉默。“那是 北极冠……，南部一大片暗区一定是Erythraeum海。哦，我看到Meridiani湾了……在西边有一片云。”国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材3 e* t2 _- W5 }+ d
初学者上前再看。仍旧什么也没有，只有一个绒球。也许北部的边缘变得亮了一些，火星也不再是均匀的橙色，但是仍然没有什么值得注意的东西。然而，下一次初学者就不再是初学者了，慢慢的亮区和暗区已经可以分辨出了。
  x' K7 _6 l: z  o4 g6 J! r2 n天文望远镜器材评测和交流论坛一个训练视觉能力的绝佳方法是画素描。不必把它做成艺术品；我们的主要目的是在你的笔记本中用比文字更直接的方法来记录细节。素描星场不需要任何艺术天赋，但是通过素描一个天区，其中包含一个暗弱的小行星或是外行星，你可以通过检查几天或是几周前的素描来识别出这些天体的位置变化。
+ i9 p/ O8 f3 N, }5 H天文家园欢迎您！对于素描行星，尝试用肉眼来画月面。如果你有锐利的视力，月亮在肉眼中所展现出的细节元比行星在望远镜中所展现的细节要多得多！画一个直径几英寸的半圆，描绘一些圆的目标，然后画出月面上明暗部分的交界线。仔细用铅笔添加主要的暗区，然后寻找一些细小的斑点。现在你一看到了许多月面上的细节，比你所能想象的要多得多。天文家园欢迎您！1 R3 _5 J* f, V. B- S) f. M; L
“教训是显然的，”英国《业余天文学家手册》的作者詹姆斯·穆尔登（James Muirden）写到，“不应该浪费任何使用望远镜训练你眼睛的机会；用不同的放大倍率观测同一目标可以看到它们的不同效果；尝试观测暗弱的恒星；画下行星的细节。在开始阶段，这看起来全是无用功；观测记录本中会充斥着无用的素描和失败的记录。但表面上无用的劳动却是必需的，因为几周之后，训练的效果就会慢慢的显现。一些被认为是极难观测或是无法观测到的天体会在第一次观测中被识别出来，一些暗弱的影像也会出现在视场中。确实，这些细节会变得如此的清晰以至于观测者会把这本质上的改善归功于观测条件的好转。但这却主要归功于你的眼睛。”
! E+ K% ^) N% C8 P$ z2 Q国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材使自己更舒适
( `* v% e( e1 P/ A. Z天文家园欢迎您！很自然，这一点会被望远镜所带来的不适或是不方便所摧毁。你需要一张桌子来放星图、红色手电、目镜、笔记本、铅笔和其他设备。对我来说，完美的解决方案是一张有四条可折叠的金属腿的牌桌。它很大，又轻且便于存放。它是我20年前在二手市场花了4美元买到。国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材8 g" m1 P5 P3 P
一个可旋转的目镜盘会带来许多便利，因此它已几乎成为了望远镜的必备附件。如果你能找到或是做一张可调节高度的观测椅，你的望远镜会向你展示一个全新的世界。
: k" p+ M$ o0 Q+ h7 g- z天文家园欢迎您！赤道仪运转中的不稳定或是速度过快都是会招致恶果的，尤其是当你没有钟转仪时。请确认望远镜已经调至平衡状态；它不应该朝一个方向运动比较容易，而朝另一个方向运动比较困难。不要害怕拆开赤道仪并且将它退还生产厂家，如果它确实不令你满意。数年前我为6英寸折射望远镜买的赤道仪转起来十分的颠簸。在尝试了几种润滑油之后，我在所有的轴承表面上都涂上了蜡。支架的夹子是螺栓式的，它们由于拧得过紧顶住了支架；我在螺栓的一端塞入了一小块皮革，并加入一些石墨粉和一些油，因此使其具有了可调节的张力。改善的效果是显著的。在高倍情况下我仍能平稳的跟踪一颗恒星，仅靠我的鼻子轻推目镜就行了。
' g- |7 |, n* s# Uwww.astroview.com.cn在冬季，你要遵从天文学家的标准建议，穿足足以低档华氏20度到30度的低温的衣服，否则你就要吃苦头了。在夏季，在驱蚊剂发明前成功的观测是如何进行的仍是一个谜。www.astroview.com.cn) L( ?% [2 D! q/ v" Q
总之，任何可以使你观测更简单、安全和舒适的努力都是值得的，无论在这之前它会带来多大的麻烦。国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材2 P# w$ q& m0 ~
天文望远镜器材评测和交流论坛" s9 l8 f* o* P: |) B  g
[ 本帖最后由 siqingtan 于 2008-4-20 17:41 编辑 ]

译自 《Sky and Telescope》天文家园欢迎您！: L& ^$ a! d& ?4 }5 e; f

+ ?7 ~& u; L% X$ D3 awww.astroview.com.cnThe Art of Using a Telescope(By: Alan MacRobert)
: [3 ^8 x! {* G; p" G  I3 H' u天文望远镜器材评测和交流论坛天文家园欢迎您！6 ~7 G; }/ d+ e/ `, i' P
Once you've obtained an astronomical telescope, what can you expect of it? Both less and more than many new owners realize. & J9 R8 _; p0 D
One of the most fun parts of being an amateur astronomer is showing off the heavens to others. The "oohs" and "aahs" at a public star party as people get their first good look at the Moon or Saturn are a pleasant reward for the proud telescope owner. Naturally, you will have aimed the scope at the most spectacular object above the horizon. Sometimes there's a temptation to show people more typical objects -- ghostly, barely visible apparitions with obscure catalog numbers -- "to give them an idea of real astronomy." The reactions then are not so encouraging, even when viewers are told they're looking at a recently recovered comet or a galaxy 40 million light-years away. # [' y1 y' C0 z' t6 ?- F
The truth is, most of the thousands of objects visible in amateur instruments are not the least bit spectacular. Anyone who gets a telescope expecting dramatic visual thrills is in the wrong hobby. 天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪4 j! y  @( y6 V; x% a% s) R
The riches that astronomy offers are of a different sort. Visual observing outdoors in the dark usually means working to detect something that's extremely faint, tiny, hard to find, or all three. The more difficult the task, however, the greater the rewards of success. The excitement lies in finding and seeing first-hand remote marvels far beyond our planet -- and in gaining skills and knowledge as an amateur scientist. . A5 m/ O5 Y4 R( @
Too many people buy a telescope as if it were a TV, expecting it to show pictures all by itself. It's more like a piano, which gives back only as much value as the work you put into it. Learning to use a telescope well is a lot easier than learning a musical instrument, however. If you're reasonably persistent and careful and are willing to practice the techniques described here, you'll soon master the skies.
; \2 L/ F) `7 i3 DKnow Your Equipment www.astroview.com.cn, [+ F4 `$ N  n
Naturally, everyone first tries out a new telescope in the daytime. This is when to become familiar with its motions, pointing, focusing, different eyepieces, and magnifying powers, so you can then do everything in the dark. 天文望远镜器材评测和交流论坛) |5 P* C9 s. ~3 i8 l3 x
The Finder. Most telescopes have a finderscope attached to the side to help aim it. You need a finder because the main telescope has such a tiny field of view -- that is, it shows such a tiny piece of sky -- that you can't tell exactly where it's pointed just by looking. 天文家园欢迎您！$ G/ u! o, Q' C  c9 L. O; U
The higher the power, the smaller the field of view. For example, at 50 power you're looking at a magnified piece of sky about as small as your little fingernail covers when held at arm's length. An 8× finderscope, on the other hand, displays about as much sky as a golf ball covers at arm's length.
! O; u8 e4 q* o天文望远镜器材评测和交流论坛This is big enough to aim at something you see with the naked eye and get it in the finderscope's view. Once it's there, you center it in the finder's crosshairs. That should be a precise enough aim for the object to appear in the view of the main telescope.
$ n3 \8 K' i; p# k1 N: WFirst things first: you'll need to adjust the finder's mounting screws so it's aimed parallel to the main telescope. In daylight, point the main scope at something at least several hundred feet away using the lowest-power eyepiece. (But not the Sun! Never look through a telescope that might get aimed at the Sun or you could blind yourself.) A distant treetop is ideal. Center it in your view. Never mind if it appears upside down. 6 t* L! [; H: r- L( ^, e5 ]" {; N1 r
Now look in the finder. See the treetop? Is it centered in the crosshairs? Adjust the screws holding the finder until the crosshairs line up on the target. Now check back in the main telescope to make sure it hasn't moved. Then switch to a high-power eyepiece in the main telescope, and repeat the operation until the finder is locked in position with perfect aim.
  p' k3 @' k8 @/ `And why, you ask, is the treetop upside down or oriented at some other weird angle? The answer is that this is an astronomical telescope, and after all, there's no up or down in space. So it doesn't matter how the field is oriented. Turning the image right-side up would require extra optical parts, adding to the expense and complication of the instrument and probably degrading its performance slightly. Therefore, "image erecting" lenses are used only in terrestrial telescopes, those intended for looking at things on Earth.
0 o8 R1 F% J# }- MNext let's turn to the mounting. As noted in the article "How to Choose a Telescope," telescope mounts come in two basic types: equatorial and altazimuth. 天文望远镜器材评测和交流论坛5 o/ W9 L0 U- P. F0 _5 s1 J
An equatorial mount allows the telescope to swing only in the directions of celestial north-south and east-west. The altazimuth goes up-down (moving in altitude) and side to side (azimuth). An altazimuth mount at least has the virtue of simplicity. An equatorial mount is ultimately more helpful, but it takes some getting used to. , A& r% l: A8 ^- t3 i
The Equatorial Mount. If this is what you have, find its polar axis (the rotating part that's more toward the base and maybe has a setting circle showing right ascension). Outdoors, place the telescope so the polar axis points roughly to where you know Polaris, the North Star, will be located after dark. The telescope's motion around this axis now traces the paths taken by celestial bodies across the sky as the Earth turns. 天文家园欢迎您！& G- V% A9 ], B, x
Sweep the telescope around its polar axis from the eastern horizon across the sky to the west to visualize nightly star paths. At first the mount's motions will seem awkward and unpredictable. But remember that no matter where the telescope is pointed, it will move only toward or away from Polaris (celestial north-south) and at right angles to this direction (celestial east-west). The orientation of these varies in different parts of the sky, but with some practice swinging the telescope around in daytime you'll get used to them.

The Fine Art of Observing
% K3 I/ R/ ]4 U) Q$ q" r1 \0 x天文家园欢迎您！The challenge of astronomy is that we must view most of the universe from extremely far away. When you're trying to see something well on Earth your instinct is to move closer for a better look. But when it comes to distant stars and galaxies, we're stuck where we are. So, ever since the dawn of telescopic astronomy, the art of observing has been the art of using your eye to the utmost of its ability.
# P- L: [2 U7 L0 M8 @Viewing tips. When looking through the telescope, focus and refocus with care. A good observer is always fiddling with the focus, trying to get it just a hair sharper. Many people find it best to keep both eyes open, since squinting strains the working eye. You can cover the "off" eye with one hand.
6 r  g2 M/ A  b: ^国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材Don't expect to see right away everything an astronomical object has to offer. The first look always shows less than comes out with continued scrutiny. This is true whether your subject is a dim galaxy that can hardly be told from the blackness of space, or detail on the Moon or a planet where the light is almost blindingly bright.
% h" p; V$ p* \4 E" ~* COne reason it takes time to see detail is the unsteadiness of the Earth's atmosphere. Celestial objects constantly shimmer and boil when viewed at high power, due to weak but ever-present heat waves in the air around and above us. The severity of this shimmering -- called the atmospheric seeing -- varies from night to night and often from minute to minute.
0 A1 g8 \, T7 h9 j7 c9 Awww.astroview.com.cnAs you watch an object quiver and churn, unsuspected detail will flicker into view during quick moments of stability when the view sharpens up, only to fade out again before you know it. The skilled observer learns to remember these good moments and ignore the rest. The quality of the atmospheric seeing is most important when viewing bright objects at high power, but it can influence the visibility of faint ones too. * W8 Q& g  V) t3 l$ X! H
The main reason it takes time to see detail, however, has to do not with the atmosphere but with the eye and mind. Wringing everything possible out of very distant views means learning new visual skills that involve active, concentrated effort.
  m9 k$ J7 [' wwww.astroview.com.cnYou'll discover that the eye's picture of a difficult object builds up rather slowly. First one detail is noticed and fixed, and you think there's nothing more to be seen. But after a few minutes another detail becomes evident, then another. www.astroview.com.cn8 s8 ^7 V% C. h: ]0 e
To convince yourself of this, look at a piece of sky with the naked eye and try to spot faint stars. Some will be visible right away; others take a few seconds to come out. When no more appear, most people would quit trying. But keep at it for a few minutes. Chances are some more will glimmer into view in places you would have sworn were blank. After a while you're seeing at least half a magnitude fainter than at first. www.astroview.com.cn, C0 ^3 B$ G2 E7 Q
The planet Mars is another classic example of this effect. For the beginner taking a first look with a small telescope, Mars ranks as the most disappointing object in the sky. It's just a tiny, featureless, orange fuzzball. The beginner steps aside to let an experienced Mars observer look in the eyepiece. Silence. "There's the north polar cap.... That big dark area in the south must be Mare Erythraeum. Okay, I've got Sinus Meridiani.... There's a cloud patch on the western limb...." 天文家园欢迎您！# P* w0 c- x+ u$ ?
The beginner looks again. Nothing but a fuzzball. Well, maybe there is a bit of brightness at the north edge crawling around in the poor seeing, and the fuzziness isn't a perfectly uniform orange, but these hardly seem like things worth noticing. Nevertheless, the next time the beginner looks he or she won't be quite a beginner, and the bright spot and dark area will come into view more readily.
5 U8 f0 u% S! Q( j# w天文望远镜器材评测和交流论坛An excellent way to train yourself to see better is to make sketches. These don't have to be works of art; the idea is just to record details in your notebook more directly than you can with words. Star fields require no artistic talent whatsoever, but by sketching a field that contains a faint asteroid or outer planet, you can identify the intruder be checking back in the next few days or weeks and seeing which one changes position.
& |- Q; h, l6 h* PFor practice sketching planets, try drawing the Moon with the naked eye. If you have reasonably sharp or well-corrected vision, the Moon shows much more detail to the naked eye than any planet will in a telescope! Make a semicircle a couple of inches in diameter by tracing some round object and then draw the terminator exactly as you see it on the Moon. Carefully add the major dark areas with pencil shading, then look for finer markings. By now you'll be seeing much more detail on the Moon's face than you ever thought possible without optical aid. 天文望远镜器材评测和交流论坛% ^- {9 t0 Y& H' j- p, h9 h
"The lesson is clear," wrote the British author James Muirden in The Amateur Astronomer's Handbook, long a classic: "No opportunity should be lost to train the eye to work with the telescope; to observe the same object with different powers so as to see the effect of magnification; to try to see faint stars; and to draw planetary markings. In the beginning, to be sure, this may all seem to be wasted effort; the observing book will fill up with valueless sketches and brief notes of failure. But this apparently empty labor is absolutely essential; for, as the weeks pass, a steady change will be taking place. Objects considered difficult or impossible to see will now be discerned at first glance, and fainter specters will have taken their place. Indeed, these former features will now be so glaringly obvious that the observer may suppose that some radical improvement has occurred in the observing conditions. But the credit belongs entirely to the eye."
% [6 k8 b, ]* G1 m" I国内专业的天文望远镜器材评测和交流论坛，致力于如高桥、televue、tmb、ap、tec等顶级望远镜和附属器材Life's Little Comforts
4 H3 X! f4 b9 |www.astroview.com.cnNaturally, this sort of concentration will be spoiled by any undue discomfort or inconvenience at the telescope. You'll need a table right at hand to hold charts, red flashlight, eyepieces, notebook, pencil, and other gear. The perfect solution for me has been a cheap cardboard card table with fold-up metal legs. It's big, very light, and easy to carry and store. I got it for $4 in a secondhand shop 20 years ago.
. ?9 E5 U6 [; K天文家园欢迎您！Nothing ruins your ability to see like having to twist and strain to look through the eyepiece. A rotating tube, which can turn in its cradle to orient the eyepiece more where you prefer, is therefore a nice plus in a small reflector and almost mandatory in a large equatorially mounted one. If you can find or make an adjustable-height observing chair, your telescope may start showing new worlds. I've used an assortment of seats from a milk crate to a stepladder.
5 ~8 S- ]& v- O& S% t天文家园欢迎您！Any jerkiness and backlash in the mount's motions can also spell doom, especially if you lack a clock drive. Make sure the telescope is balanced properly by adjusting any counterweights; it shouldn't move in one direction more easily than in another. Don't be afraid to take a mount apart and lubricate it, or return it to the manufacturer if it's truly unsatisfactory. The mount I bought for my 6-inch reflector years ago was originally quite jerky. After trying various lubricants, I settled on candle wax rubbed onto all the bearing surfaces. The mount's "clamps" were merely bolts that tightened head-on against the shafts; I epoxied small pieces of leather to the bolt ends, impregnated these with graphite powder and a little oil, and thus gained adjustable tension. The improvement was enormous. At high power I could follow the stars with a smooth, continuous motion just by touching the side of my nose against the eyepiece.
/ G+ t6 K+ j, `6 N0 O天文望远镜器材评测和交流论坛In wintertime, you can either heed the astronomer's standard advice to dress for 20°F to 30°F colder than the actual temperature, or you can learn the hard way. As for the summer, it remains a mystery how successful observations were performed before the invention of mosquito repellent. 天文望远镜器材评测和交流论坛  _8 y, b$ f; ?3 Y+ W: _
In short: Anything that makes your observing easier, surer, or more relaxed, no matter how much trouble it takes beforehand, is worth the effort.
0 F8 N. [; a2 _7 l% \2 C4 m天文家园欢迎您！　
# c. a: T1 C+ S  a; H" f* hwww.astroview.com.cn
" z% ]9 b  e5 K4 A- u  n天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪
, t# o- I* e, K. K- P4 oFrom 《Sky and Telescope》
8 q$ X! D6 s( i5 ^: z0 X7 O* ^2 w+ ^& i天文论坛,天文,望远镜,天文望远镜,apo,ed,televue,tv,tmb,高桥,ap,tec,望远镜评测，望远镜测评,双筒望远镜，天顶，目镜，望远镜配件，赤道仪
$ \* r' p9 R1 P! b/ k+ n+ T1 K2 Owww.astroview.com.cnRobert J.T. Yan
8 d' {4 J' @8 x' Vhttp://www.astroblog.cn/RobertYan/category/8.html/rss

相当好的入门介绍！

漂亮,学习一次

学习了一遍，  谢谢！

非常好的入门文章`!~