{"slug":"astro-beginner-guide-1","title":"这可能是最详细的星空摄影入门教程，果断收藏！ (上)","author":"Thomas看看世界","date":"2018-04-15","wechat":"https://mp.weixin.qq.com/s?__biz=MzI4NDA5MzE5NQ==&mid=2247486691&idx=1&sn=adf0bf7c1816338d8d13daab70e2ea9e&chksm=eb81f287dcf67b9156c24da637081aade592e023b3f78cb38d238b98ae426ecbcb3493c948dd&scene=21#wechat_redirect","blocks":[{"t":"h","x":"引言","xe":"Introduction"},{"t":"p","x":"天体物理学有个浪漫的说法：星空是你身上每个原子的故乡。如果你曾在远离都市的某个地方看过夜空中流淌的星河，一定有过这样的感受，璀璨的星光将世俗的双眼洗刷得干净透彻， 心灵寻得片刻的宁静。","b":false,"xe":"Astrophysics has a romantic saying: the starry sky is the hometown of every atom in your body. If you have ever watched the river of stars flowing across the night sky far from the city, you know the feeling — the brilliant starlight washes your worldly eyes clean, and your mind finds a moment of peace."},{"t":"p","x":"星空季又到了，喜欢摄影的你是不是蠢蠢欲动却被不知从何下手而困扰呢？星空题材看似高深，但其实掌握了相关天文知识和拍摄技巧后，很多新手都可以拍摄成功。正文之前，先来欣赏几张星空美图吧。","b":false,"xe":"Milky Way season is here again. If you love photography, are you itching to shoot but unsure where to start? The night sky may seem like an advanced subject, but once you master the relevant astronomy knowledge and shooting techniques, even many beginners can succeed. Before the main text, let's enjoy a few beautiful star photos first."},{"t":"img","f":"img-01","w":1024,"h":1481},{"t":"img","f":"img-02","w":1080,"h":408},{"t":"img","f":"img-03","w":1024,"h":705},{"t":"img","f":"img-04","w":1080,"h":722},{"t":"p","x":"（本文中星空照片全部为作者本人拍摄，更多照片请看图虫个人主页 ID:JingshuZhu","b":false,"xe":"(All night-sky photos in this article were shot by the author. For more, see my Tuchong homepage, ID: JingshuZhu,"},{"t":"h","x":"及微信：JingshuZhu）","xe":"or WeChat: JingshuZhu)"},{"t":"p","x":"网络上星空摄影教程屡见不鲜，我试图将这些碎片化的知识点结合自己的经验，整理成系列教程， 全面地讲解前期拍摄技术和后期思路，并用实例详细介绍后期处理的每一步骤。","b":false,"xe":"There is no shortage of astrophotography tutorials online. I've tried to combine these fragmented bits of knowledge with my own experience into a series of tutorials that systematically explain field technique and post-processing thinking, using real examples to detail every editing step."},{"t":"p","x":"星空摄影系列教程拟分为：","b":false,"xe":"The astrophotography tutorial series is planned as:"},{"t":"p","x":"星空摄影技巧揭秘 (上)","b":false,"xe":"Astrophotography Techniques Revealed (Part 1)"},{"t":"p","x":"星空摄影技巧揭秘 (下)","b":false,"xe":"Astrophotography Techniques Revealed (Part 2)"},{"t":"p","x":"星空全景接片前期后期技术详解","b":false,"xe":"A Detailed Guide to Night-Sky Panorama Stitching, Field and Post"},{"t":"p","x":"本文将从以下几方面系统讲解：","b":false,"xe":"This article systematically covers the following:"},{"t":"h","x":"上篇","xe":"Part 1"},{"t":"h","x":"下篇","xe":"Part 2"},{"t":"h","x":"1. 相关天文知识","xe":"1. Relevant astronomy knowledge"},{"t":"h","x":"1. 降噪处理","xe":"1. Noise reduction"},{"t":"h","x":"· 南北半球银河特点及差异","xe":"· Milky Way characteristics and differences between the hemispheres"},{"t":"h","x":"· 噪点类型及特征","xe":"· Noise types and their traits"},{"t":"h","x":"· 如何利用月光为照片增色","xe":"· How to use moonlight to enhance your photos"},{"t":"h","x":"· 五种常见降噪方法适用情况","xe":"· When to use five common noise-reduction methods"},{"t":"h","x":"2. 拍摄条件","xe":"2. Shooting conditions"},{"t":"h","x":"· 堆栈降噪实例","xe":"· A stacking noise-reduction example"},{"t":"h","x":"3. 拍摄器材","xe":"3. Shooting gear"},{"t":"h","x":"2. 星轨拍摄技法","xe":"2. Star-trail technique"},{"t":"h","x":"4. 银河拍摄技法","xe":"4. Milky Way shooting technique"},{"t":"h","x":"· 拍摄时间","xe":"· Shooting time"},{"t":"h","x":"· 星空拍摄参数","xe":"· Night-sky camera settings"},{"t":"h","x":"· 拍摄方位","xe":"· Shooting direction"},{"t":"h","x":"· 四种利用光源拍摄地景方法","xe":"· Four ways to light the foreground"},{"t":"h","x":"· 拍摄器材","xe":"· Shooting gear"},{"t":"h","x":"· 手动对焦技巧","xe":"· Manual focus technique"},{"t":"h","x":"· 拍摄方法","xe":"· Shooting method"},{"t":"h","x":"· 景深合成","xe":"· Focus stacking"},{"t":"h","x":"· 堆栈叠加后期处理","xe":"· Stacking in post"},{"t":"p","x":"星空摄影可以大致分为两大类：深空摄影（天体摄影）以及星野摄影。深空摄影一般情况下指以拍摄深空天体为主要目的的摄影门类， 包括月亮，太阳，星云和星团等，又可分为纯深空天体和广域深空两大类，需要使用昂贵的特殊专业设备，诸如导星设备、赤道仪、冷冻CCD、天文望远镜等等。此类题材属于天文摄影，在此不做深入讨论。而星野摄影主要是以拍摄地景加星空（银河、星轨、流星雨等）的拍摄方式，风光摄影中的星空摄影通常是指这一类。相比深空摄影，星野摄影的起点并不高，更注重构图和后期调色等技巧。","b":false,"xe":"Astrophotography can be roughly divided into two categories: deep-sky photography (celestial photography) and landscape astrophotography. Deep-sky photography generally aims at deep-sky objects — the Moon, the Sun, nebulae, star clusters — and falls into pure deep-sky and wide-field deep-sky, requiring expensive specialized equipment such as autoguiders, equatorial mounts, cooled CCDs, and telescopes. That subject belongs to astronomical photography and won't be discussed in depth here. Landscape astrophotography mainly combines terrestrial scenery with the night sky (the Milky Way, star trails, meteor showers), and night-sky photography in landscape work usually means this category. Compared with deep-sky photography, its barrier to entry is low, with more emphasis on composition and color grading."},{"t":"p","x":"1","b":false,"xe":"1"},{"t":"p","x":"相关天文知识","b":false,"xe":"Relevant Astronomy Knowledge"},{"t":"p","x":"为什么别人的照片漫天繁星闪烁，而你兴致勃勃去拍银河，照片中却是星光疏落，失望而归，根本的原因就是银河没有出现在你拍摄的夜空中。星空摄影是较为特殊的题材，不仅需要精湛的前期和后期技术，了解相关的天文知识是拍摄成功的关键。","b":false,"xe":"Why do other people's photos overflow with stars while your excited Milky Way outing yields sparse, disappointing starlight? The fundamental reason is that the Milky Way simply wasn't in the night sky you shot. Night-sky photography is a special subject: beyond solid field and post technique, understanding the relevant astronomy is the key to success."},{"t":"img","f":"img-05","w":1080,"h":721},{"t":"h","x":"南北半球银河特点及差异","xe":"Milky Way Characteristics and Differences Between the Northern and Southern Hemispheres"},{"t":"p","x":"银河（Milky Way）是指横跨天空的一条乳白色亮带，是无数恒星发出的光，各部分的亮度和宽窄不等，最窄只有 4～5°，最宽约 30°。其实一年四季的夜晚都可以看到银河，但由于银心是最明亮壮观的部分，拍摄银河在摄影的概念中通常是指拍摄银心部分。","b":false,"xe":"The Milky Way is a milky-white band of light stretching across the sky — light from countless stars. Its width and brightness vary: 4-5° at its narrowest and about 30° at its widest. You can actually see the Milky Way on nights year-round, but since the galactic core is its brightest and most spectacular part, \"shooting the Milky Way\" in photographic terms usually means shooting the core."},{"t":"p","x":"有过星空拍摄经验的朋友都知道，银心在夜空中出现的方向和时间在每个月和每个季节是不同的，拍摄前的周密计划是拍摄成功的保证。在北半球，夏天的夜晚可以看到银河最璀璨的银心，而冬季只能看到暗淡的悬臂部分，南半球反之。为什么会有这种时间和方位的差异呢？首先我们需要了解地球、太阳系和银河系之间的关系。","b":false,"xe":"Anyone with night-sky experience knows the galactic core appears in different directions and at different times each month and season, so careful planning before a shoot is the guarantee of success. In the Northern Hemisphere, summer nights reveal the dazzling core, while winter shows only the faint arms — the reverse holds in the Southern Hemisphere. Why these differences in time and direction? First we need to understand the relationship between the Earth, the solar system, and the Milky Way."},{"t":"p","x":"大家都知道月亮绕地球转动，地球及其他行星绕著太阳旋转，太阳和其他星系绕着银河的中心旋转。但是太阳系和银河系不在同一平面，由于旋转角度的关系，所以在不同季节我们看到的银河的位置是不断变化的。但是如果拍摄点不变，相邻几天的同一时间， 银心在天空的出现位置是基本相同的，每一天位置的微小变化可忽略。","b":false,"xe":"Everyone knows the Moon orbits the Earth, the Earth and other planets orbit the Sun, and the Sun and other stars orbit the center of the Milky Way. But the solar system and the Milky Way are not in the same plane, and because of the angle of rotation, the Milky Way's position in our sky changes with the seasons. However, if your shooting spot stays the same, the core appears at essentially the same position at the same time on consecutive days — the tiny daily shift is negligible."},{"t":"p","x":"总体来说，北半球大部分地区三月至十月可以拍到银心，南半球大部分地区二月至十月可以拍到银心，其它月份只能拍到银河的悬臂部分。但每个月的拍摄时间都不一样，平均每月向后延迟两小时左右，所以在二、三月份凌晨银心从地平线升起，而十月份是日落之后银心会逐渐落到地平线之下。 在北半球的冬季和南半球的夏季，由于银心是在白天时段升起，我们自然是看不到的，这是因为地球公转的位置使太阳和银心在一条线上。","b":false,"xe":"In general, the galactic core can be photographed from most of the Northern Hemisphere between March and October, and from most of the Southern Hemisphere between February and October; in other months only the galactic arms are visible. The shooting window shifts each month, averaging about two hours later per month: in February and March the core rises above the horizon before dawn, while in October it sinks below the horizon after sunset. In the Northern Hemisphere winter and Southern Hemisphere summer, the core rises during daytime so we naturally can't see it — Earth's orbital position puts the Sun in line with the core."},{"t":"img","f":"img-06","w":1000,"h":809},{"t":"p","x":"由于地理位置和地轴偏角的关系，南北半球看到的银河形状和方位都是不同的。星空摄影要符合自然规律，照片中的景象应该是在自然界的某一时刻会出现的，切忌不可后期PS成不符合自然规律的画面，闹出笑话。","b":false,"xe":"Due to geography and the tilt of Earth's axis, the shape and orientation of the Milky Way differ between the hemispheres. Night-sky photography must obey the laws of nature: the scene in your photo should be one that could actually occur at some moment in nature. Never composite something in post that violates these laws, or you'll make a laughingstock of yourself."},{"t":"h","x":"拍摄银河，南半球的自然条件比北半球略好，不同之处可归纳为以下几点：","xe":"For shooting the Milky Way, the Southern Hemisphere's natural conditions are slightly better than the Northern Hemisphere's. The differences can be summarized as follows:"},{"t":"img","f":"img-07","w":549,"h":457},{"t":"p","x":"1","b":false,"xe":"1"},{"t":"p","x":"在赤道是可以看到所有的星座，越往北看到的南天星空越少，越往南看到的北天星空越少，所以南半球的大小麦哲伦星云在北半球是看不到的。","b":false,"xe":"From the equator you can see all constellations; the farther north you go, the less of the southern sky you see, and vice versa. So the Large and Small Magellanic Clouds of the Southern Hemisphere are invisible from the Northern Hemisphere."},{"t":"p","x":"2","b":false,"xe":"2"},{"t":"p","x":"·","b":false,"xe":"·"},{"t":"p","x":"4月-7月是拍摄银河最合适的季节，此时北半球是春夏季而南半球是秋冬季。","b":false,"xe":"April to July is the best season for shooting the Milky Way — spring/summer in the Northern Hemisphere and autumn/winter in the Southern Hemisphere."},{"t":"p","x":"3","b":false,"xe":"3"},{"t":"p","x":"南半球在东南方向和西南方向拍摄到的银河形状呈反向，而北半球只能拍摄到同一形态银河。","b":false,"xe":"In the Southern Hemisphere, the Milky Way appears mirrored when shooting southeast versus southwest, while the Northern Hemisphere only ever shows one orientation."},{"t":"p","x":"4","b":false,"xe":"4"},{"t":"p","x":"北半球的银心位置通常能与地景很好地结合，但是在南半球随着银心升高到一定位置，就不能与地景结合，不利于构图。特别是从八月至10月天黑之后，东南方向银心已经离开地平线很远，除非地景有高山否则很难与前景结合，但是可以向西南方向拍摄银河，银心形态呈反向。","b":false,"xe":"In the Northern Hemisphere, the core's position usually combines well with the foreground. In the Southern Hemisphere, once the core climbs high enough it no longer combines with the landscape, hurting composition. Especially from August to October after dark, the core in the southeast is already far above the horizon — unless your foreground has tall mountains it hardly combines — but you can shoot toward the southwest, where the core's shape appears mirrored."},{"t":"img","f":"img-08","w":1024,"h":714},{"t":"p","x":"南半球的东向银河","b":false,"xe":"The east-facing Milky Way in the Southern Hemisphere"},{"t":"img","f":"img-09","w":1080,"h":881},{"t":"p","x":"南半球的西向银河","b":false,"xe":"The west-facing Milky Way in the Southern Hemisphere"},{"t":"h","x":"如何利用月光为照片增色","xe":"How to Use Moonlight to Enhance Your Photos"},{"t":"p","x":"星空摄影是在夜晚，这就不可避免地涉及到月亮。由于月光的亮度很强，当一轮明月高悬夜空的时候，很多星星被月亮的光芒覆盖，可见的星星寥寥无几，月朗星稀就是指这样的景象。如果在这样的情况拍摄星空，月光会直接影响银河的亮度，拍出的效果非常不理想。如何确定最佳拍摄日期，了解月相是星空摄影的必修课。","b":false,"xe":"Night-sky photography happens at night, which inevitably involves the Moon. Because moonlight is bright, when a full moon hangs high it overwhelms most stars — only a sparse few remain visible, exactly what the Chinese idiom \"bright moon, sparse stars\" describes. Shooting the night sky under such conditions, moonlight directly weakens the Milky Way's brightness and the results are far from ideal. To pick the best shooting dates, understanding moon phases is a required course in night-sky photography."},{"t":"p","x":"很多人以为月亮是晚上升起来的，这个概念是错误的。月亮每天升起的时间比前一天大约推迟50分钟，所以月升月落并不和白天夜晚同步，有时月亮会在白天升起，这也就是为什么会出现日月同辉的场景。这样在每个月中都会遇到整夜没有月亮的日子，也会出现整夜都有月亮的情况。","b":false,"xe":"Many people assume the Moon rises at night — that's wrong. Moonrise shifts about 50 minutes later each day, so moonrise and moonset are not synchronized with day and night. Sometimes the Moon rises during the day, which is why you can see the Sun and Moon shining together. Every month includes days with no moon all night, and also nights with a moon all night long."},{"t":"p","x":"“人有悲欢离合，月有阴晴圆缺”，这里的圆缺就是指“月相变化”，是在地球上所看到的月球被日光照亮部分的不同形象。月相按照形状来分，总共有八种。周期是一个月，按数序来分别是（如图）：新月→娥眉月→上弦月→凸月→满月→凸月→下弦月→娥眉月→新月。","b":false,"xe":"\"People have their sorrows and joys, partings and reunions; the moon has its dark and clear, waxing and waning\" — this waxing and waning is the change of moon phases: the different appearances of the sunlit portion of the Moon as seen from Earth. There are eight phases by shape, cycling through one month in order (as shown): new moon → waxing crescent → first quarter → waxing gibbous → full moon → waning gibbous → last quarter → waning crescent → new moon."},{"t":"img","f":"img-10","w":468,"h":422},{"t":"h","x":"月相图","xe":"Moon phase diagram"},{"t":"p","x":"新月（约在农历三十或初一）","b":false,"xe":"New moon (around the 30th or 1st of the lunar month)"},{"t":"p","x":"娥眉月（约在农历的初三、初四）","b":false,"xe":"Waxing crescent (around the 3rd-4th of the lunar month)"},{"t":"p","x":"上弦月（约农历初七、初八）","b":false,"xe":"First quarter (around the 7th-8th of the lunar month)"},{"t":"p","x":"渐盈凸月（约在农历十一、十二）","b":false,"xe":"Waxing gibbous (around the 11th-12th of the lunar month)"},{"t":"p","x":"满月（农历十五或十六）","b":false,"xe":"Full moon (the 15th or 16th of the lunar month)"},{"t":"p","x":"渐亏凸月（约在农历十六——农历二十二左右）","b":false,"xe":"Waning gibbous (around the 16th-22nd of the lunar month)"},{"t":"p","x":"下弦月（约在农历二十二、二十三）","b":false,"xe":"Last quarter (around the 22nd-23rd of the lunar month)"},{"t":"p","x":"残月（约在农历二十四左右——月末）","b":false,"xe":"Waning crescent (around the 24th of the lunar month to month's end)"},{"t":"p","x":"拍摄银河时如何避开太强的月光，一是可以选择在月升之前或月落之后拍摄；二是在峨眉月的时期，这也是我比较喜欢的拍摄条件，月光不是很强，对银河的影响不大，同时又可照亮地景，起到补光的作用。","b":false,"xe":"To avoid overly strong moonlight when shooting the Milky Way: first, you can shoot before moonrise or after moonset; second, shoot during the crescent-moon period — my favorite condition — when the moonlight is not too strong, barely affects the Milky Way, and also illuminates the foreground as fill light."},{"t":"p","x":"善用月亮这个自然元素会令你的照片增色不少，一种比较高级的拍摄方法是在月升的时刻拍摄银河，画片上呈现银河与月亮共存的景观。月升和日出的感觉相似，都是红光四射，但在黑夜中看着温暖的光芒洒向大地，那种感觉更为奇幻。 由于只有短暂的几分钟拍摄时间，月亮升起后就会严重影响银河的亮度，因此这种拍法要求精密的前期策划和娴熟的拍摄技术。","b":false,"xe":"Making good use of the Moon as a natural element adds a lot to your photos. A more advanced technique is shooting the Milky Way at the moment of moonrise, capturing the Milky Way and the Moon in the same frame. Moonrise feels similar to sunrise — red light radiating in all directions — but watching warm light spill across the land in the dark of night feels even more magical. Because the shooting window lasts only a few minutes before the risen Moon seriously dims the Milky Way, this approach demands precise planning and practiced technique."},{"t":"img","f":"img-11","w":1024,"h":684},{"t":"img","f":"img-12","w":1024,"h":692},{"t":"p","x":"2","b":false,"xe":"2"},{"t":"p","x":"拍摄条件","b":false,"xe":"Shooting Conditions"},{"t":"h","x":"天气","xe":"Weather"},{"t":"p","x":"晴朗无云或者略有薄云的夜空，参考天气预报和卫星云图","b":false,"xe":"A clear or only slightly cloudy night sky — consult weather forecasts and satellite cloud imagery"},{"t":"img","f":"img-13","w":1080,"h":721},{"t":"p","x":"薄云有柔光罩的作用，令画面中的星光呈现梦幻效果","b":false,"xe":"Thin clouds act like a diffuser, giving the starlight in your frame a dreamy quality"},{"t":"h","x":"地点","xe":"Location"},{"t":"p","x":"城市光污染会影响拍摄，因此需要寻找光污染较少的地方，同时大气也会影响拍摄，海拔较高的区域空气更为纯净。下面几个网站可查询全球光污染情况：","b":false,"xe":"City light pollution affects shooting, so look for places with little light pollution. The atmosphere also matters — higher elevations have cleaner air. The following websites let you check light pollution worldwide:"},{"t":"p","x":"www.lightpollutionmap.info","b":false,"xe":"www.lightpollutionmap.info"},{"t":"p","x":"http://darksitefinder.com/maps/world.html","b":false,"xe":"http://darksitefinder.com/maps/world.html"},{"t":"p","x":"https://blue-marble.de/nightlights","b":false,"xe":"https://blue-marble.de/nightlights"},{"t":"img","f":"img-14","w":1024,"h":762},{"t":"p","x":"《千沟万壑》 摄于澳大利亚荒凉的中部地区，远离城市且空气纯净，璀璨的银河高悬在夜空，肉眼清晰可见。这里拍摄出的银河细节与离开悉尼两三百公里的近郊地区大不相同。","b":false,"xe":"\"A Thousand Ravines\" was shot in the desolate center of Australia, far from cities with pristine air, where the brilliant Milky Way hangs high and is clearly visible to the naked eye. The galactic detail captured here is completely different from what you'd get in the suburbs just 200-300 km from Sydney."},{"t":"h","x":"时间","xe":"Time"},{"t":"p","x":"首先要确定大的时间范围，即银河拍摄季节，其次要查询当前银心升起或落下时间，然后结合月相判断适合拍摄的最佳日期和时间。手机中的APP星空预测软件PlanIt! For Photographers, Photopills, Distant Suns, Stellarium 等都有非常精确的银河及月亮的信息，在拍摄前就可以做出周密的计划。","b":false,"xe":"First determine the broad window — the Milky Way season — then check the current core rise/set times, and finally combine moon phases to pick the best date and time. Mobile apps such as PlanIt! For Photographers, PhotoPills, Distant Suns, and Stellarium all provide very precise Milky Way and Moon information, so you can make a thorough plan before heading out."},{"t":"p","x":"3","b":false,"xe":"3"},{"t":"p","x":"拍摄器材","b":false,"xe":"Shooting Gear"},{"t":"h","x":"相机","xe":"Camera"},{"t":"p","x":"高感全画幅相机，相对APS画幅相机最大的优势之一就是高感画质，因为星空摄影要用到ISO3200-6400，甚至ISO12800，高感表现力对画质非常重要。","b":false,"xe":"A full-frame camera with good high-ISO performance — one of its biggest advantages over APS-C is high-ISO image quality, because night-sky photography uses ISO 3200-6400 or even ISO 12800, making high-ISO performance crucial."},{"t":"h","x":"镜头","xe":"Lens"},{"t":"p","x":"大光圈超广角镜头，星空摄影需要把地景和星空都拍摄进画面，超广角镜头视角宽阔，有利于构图。","b":false,"xe":"A fast ultra-wide lens. Night-sky photography needs both foreground and sky in frame, and an ultra-wide's broad field of view helps composition."},{"t":"p","x":"尼康14-24mm F2.8、蔡司15mm F2.8是很好的星空摄影镜头。最近市场上新出现几个大光圈定焦广角镜头，诸如Sigma 14mm F1.8, 老蛙12mm F2.8等等，都是星空摄影的利器。当然这些镜头也有价格昂贵，畸变控制不好，太重等等弊端，还是要根据自己的情况和能力综合考虑。除了主力镜头，我也使用三洋14mm/F2.8拍摄银河，这是性价比非常高的一个大光圈广角镜头。","b":false,"xe":"The Nikon 14-24mm f/2.8 and Zeiss 15mm f/2.8 are excellent night-sky lenses. Several new fast wide-angle primes have recently appeared on the market — the Sigma 14mm f/1.8, Laowa 12mm f/2.8, and others — all great tools for night-sky work. Of course, these lenses have drawbacks too: expensive, imperfect distortion control, heavy. Consider your own situation and budget. Besides my main lenses, I also shoot the Milky Way with the Samyang 14mm f/2.8, a fast wide-angle with exceptional value for money."},{"t":"h","x":"三脚架","xe":"Tripod"},{"t":"p","x":"星空摄影都需要长时间曝光，稳固的三脚架和球头是必须的。","b":false,"xe":"Night-sky photography always involves long exposures, so a sturdy tripod and ball head are essential."},{"t":"h","x":"头灯&手电","xe":"Headlamp & Flashlight"},{"t":"p","x":"为了避免光污染，星空摄影的拍摄地都在远离城市的偏远地区，在黑暗的环境中照明设备非常重要，任何时候安全第一是首要原则。这是常常被掉以轻心的附件，由于不够重视我也有过极为深刻的教训。一次拍摄中我和同伴的头灯都没电了，而且手机所剩电量无几，在伸手不见五指的国家公园中依靠手机微弱的光亮摸黑走出来。自此之后每次外拍，我一定会把两个头灯装在包中，同时带上备用电池。头灯和手电的另一作用就是给前景补光，并有助于对焦。快门线、GPS、御寒衣物、驱蚊液等也是必备附件。","b":false,"xe":"To avoid light pollution, night-sky locations are always far from cities, and in the dark a light source is vital — safety first, always. This is an often-underestimated accessory, and my own lack of attention once taught me a profound lesson. On one shoot, both my and my companion's headlamps died and our phones were nearly drained; we groped our way out of a pitch-black national park by the phones' faint glow. Ever since, I always pack two headlamps plus spare batteries. Headlamps and flashlights also serve to light-paint the foreground and aid focusing. A shutter release, GPS, warm clothing, and mosquito repellent are essential accessories too."},{"t":"img","f":"img-15","w":1024,"h":702},{"t":"p","x":"4","b":false,"xe":"4"},{"t":"p","x":"银河拍摄技法","b":false,"xe":"Milky Way Shooting Technique"},{"t":"p","x":"星空摄影我们应该拍什么？很多人认为拍到银河或星轨就成功了，忽略地景是普遍问题。在本章的开端就已介绍过，星野摄影不是天文摄影，属于风光摄影之中的一类，因此和风光摄影中其它题材的概念是一致的。前景（地景）的选取直接关系照片的成败，银河就像太阳和云彩一样，只是照片中的大环境，构图时要和地景配合。最常见的误区就是一味追求星空的细节，而忽略了照片的整体构图。","b":false,"xe":"What should we actually shoot in night-sky photography? Many people think capturing the Milky Way or star trails is success — neglecting the foreground is the universal problem. As explained at the start of this chapter, landscape astrophotography is not astronomical photography; it belongs to landscape photography, and the same principles apply as for any other landscape subject. The choice of foreground directly determines a photo's success or failure. The Milky Way is like the sun and clouds — just the backdrop of the photo — and must be composed together with the foreground. The most common mistake is pursuing star detail alone while ignoring overall composition."},{"t":"p","x":"从拍摄技术上来讲，星空摄影的前期和后期相比于其它题材较为复杂。因为光污染会影响星空的亮度，我们会选择黑暗的地区拍摄，在弱光环境下如何拍摄出曝光正常的照片成为最大的挑战。虽然长时间曝光可以解决拍摄地景的问题，但是由于地球的自传导致星星在天空中的位置不是固定的，而是相对地球旋转。如果曝光时间过长，会出现星星“拉线”而产生星轨的问题。那么如何保证星星不拖尾又能曝光正常呢？下面就星空和地景两方面分别说明。","b":false,"xe":"Technically, both the field and post work of night-sky photography are more complex than other subjects. Because light pollution dims the sky, we shoot in dark locations, and exposing correctly in such low light becomes the biggest challenge. Long exposures could solve the foreground problem, but Earth's rotation means the stars' positions are not fixed — they rotate relative to the Earth. If the exposure is too long, the stars trail into streaks. So how do you keep stars sharp while still exposing properly? Let me explain the sky and the foreground separately."},{"t":"img","f":"img-16","w":919,"h":1024},{"t":"h","x":"星空拍摄参数","xe":"Night-Sky Camera Settings"},{"t":"p","x":"首先要用手动拍摄模式M档预设好参数，重点要控制曝光时间以确保星星不会变成星轨，可以应用500法则，即曝光时间（秒）小于或等于500除以镜头焦距（mm）。比如拍摄的镜头焦距16mm, 500除以16 约为30秒，那么拍摄时间不要超过30秒。如果想更好地控制边角的星星拉线，建议应用400法则400/16=25秒。注意以上适用于全画幅相机，如果是APS画幅相机曝光时间要再除以系数（Crop Factor）。","b":false,"xe":"First, preset your parameters in manual (M) mode. The key is controlling exposure time so stars don't turn into trails — apply the 500 rule: exposure time (seconds) ≤ 500 divided by lens focal length (mm). For example, at 16mm, 500/16 ≈ 30 seconds, so don't exceed 30 seconds. For even better control of corner star trailing, use the 400 rule: 400/16 = 25 seconds. Note that this applies to full-frame cameras; for APS-C, divide by the crop factor as well."},{"t":"p","x":"如此黑暗的环境用这么短的曝光时间导致很多人拍出的照片一片漆黑，这就涉及到另外两个参数的组合了，大光圈和高ISO是拍摄出亮丽银河的保证。ISO建议3200-6400，这么高的感光度不是会使画面布满噪点吗？这个问题会在后面的降噪部分列举几种方案，现在各种降噪大法已经完全可以解决这个问题。光圈最好是F2.8以上，F4是底限，光圈越大拍摄出银河的细节越多。","b":false,"xe":"Such short exposures in such darkness lead many people to produce pitch-black photos, which brings in the other two parameters: a wide aperture and high ISO are the guarantee of a bright Milky Way. I recommend ISO 3200-6400. Won't such high sensitivity fill the image with noise? Several solutions are listed in the noise-reduction section later — modern noise-reduction methods handle this completely. The aperture should ideally be f/2.8 or faster, with f/4 as the limit; the larger the aperture, the more Milky Way detail you capture."},{"t":"h","x":"四种利用光源拍摄地景方法","xe":"Four Ways to Light the Foreground"},{"t":"p","x":"在没有任何辅助照明的情况下，用上面的参数组合拍摄地景会曝光严重不足，漆黑一片没有细节，如何解决这个问题？","b":false,"xe":"With no auxiliary lighting, shooting the foreground at the above settings will be severely underexposed — pitch black with no detail. How do we solve this?"},{"t":"p","x":"01","b":false,"xe":"01"},{"t":"p","x":"最好的办法是在峨眉月前后的夜晚拍摄，利用月亮给地景补光，大自然的光源最为均匀自然。理论上月面不超过1/3都是较为理想的情况，但是月光也会影响到银河的细节，月光越强银河细节越弱。","b":false,"xe":"The best approach is shooting on nights around the crescent moon, using the Moon to light the foreground — nature's light source is the most even and natural. In theory, up to about a third of the lunar disk illuminated is ideal, but moonlight also weakens the Milky Way's detail: the stronger the moonlight, the weaker the galactic detail."},{"t":"img","f":"img-17","w":1024,"h":683},{"t":"h","x":"《马头石》拍摄于峨眉月与上弦月之间的日期","xe":"\"Horse Head Rock\" was shot on a date between the crescent and first-quarter moon"},{"t":"p","x":"02","b":false,"xe":"02"},{"t":"p","x":"实际情况常受客观条件限制，并不是每次都可以选择有峨眉月的夜晚，有时要在月升之前或月落之后拍摄，这时我们可以利用照明设备如头灯或手电等对前景进行人工补光。这种补光技术需要反复练习才能做到自然均匀，不可太过生硬。","b":false,"xe":"In practice we're often constrained by circumstances — not every shoot can fall on a crescent-moon night, and sometimes we must shoot before moonrise or after moonset. Then we can use lighting gear such as headlamps or flashlights to artificially light the foreground. This light-painting technique takes repeated practice to look natural and even — it mustn't be harsh."},{"t":"img","f":"img-18","w":738,"h":1024},{"t":"p","x":"《金字塔》拍摄于阴历二十九，整晚无月光，用头灯给地景补光","b":false,"xe":"\"The Pyramid\" was shot on the 29th of the lunar month with no moonlight all night; the foreground was lit with a headlamp"},{"t":"p","x":"03","b":false,"xe":"03"},{"t":"p","x":"另一方式是利用不同时段（通常在蓝调时段Blue Hour和夜晚）分别拍摄星空和地景后期合成，可以日落后先拍地景，银心升起之后再拍星空，或先拍星空，黎明时分拍摄前景。这种方法的好处是低ISO拍摄地景，画质大幅提升，但前提是确保相机的位置要在拍摄时段内不移动。如果是在海边拍摄，要提前查询拍摄时段的潮汐涨落情况。","b":false,"xe":"Another approach is shooting the sky and foreground at different times (usually Blue Hour and night) and compositing them in post: shoot the foreground right after sunset and the sky after the core rises, or shoot the sky first and the foreground around dawn. The benefit is shooting the foreground at low ISO for a big image-quality boost — but the prerequisite is that the camera must not move between sessions. If shooting by the sea, check the tide schedule for your shooting window in advance."},{"t":"img","f":"img-19","w":708,"h":1024},{"t":"p","x":"地景：ISO200, F16, 10秒 （蓝调时段拍摄）","b":false,"xe":"Foreground: ISO 200, f/16, 10 seconds (shot during Blue Hour)"},{"t":"p","x":"星空：ISO4000, F4, 20秒","b":false,"xe":"Sky: ISO 4000, f/4, 20 seconds"},{"t":"p","x":"04","b":false,"xe":"04"},{"t":"p","x":"除了补光，还可以根据情况对地景进行几分钟以上的长曝光，后期在Photoshop中利用蒙版分别取天空和地景两张合成。但是高ISO和长曝光会产生大量噪点，建议打开相机中的长曝光降噪或多张堆栈并拍摄黑场降噪提高画质。这种拍摄方法无论前期拍摄和后期处理都比较耗时。","b":false,"xe":"Besides fill light, you can also give the foreground a long exposure of several minutes or more as conditions allow, then composite sky and foreground with masks in Photoshop. But high ISO and long exposures generate heavy noise, so enable in-camera long-exposure noise reduction, or stack multiple frames and shoot dark frames for noise reduction. This method is time-consuming both in the field and in post."},{"t":"h","x":"手动对焦技巧","xe":"Manual Focus Technique"},{"t":"p","x":"在黑暗的环境中相机不能完成自动对焦，星空摄影要转换成手动对焦模式，打开实时取景把图像放大，调节对焦环，直到星星清楚。当对前景对焦时，如果显示屏看不清楚细节，可以用头灯照亮前景帮助对焦。","b":false,"xe":"In the dark the camera can't autofocus, so switch to manual focus for night-sky work: open live view, magnify the image, and turn the focus ring until the stars are sharp. When focusing on the foreground, if the screen doesn't show enough detail, light the foreground with a headlamp to assist focusing."},{"t":"p","x":"这里介绍一个偷懒的小技巧，前提是前景离相机不可太近，至少3米以外，用16mm的超广角镜头拍摄，根据超焦距原理，只要对焦在5米以外，画面中的景物都是清晰的。为了保险起见，我一般对焦在7-8米左右的位置。","b":false,"xe":"Here's a lazy-person trick, provided the foreground is not too close — at least 3 meters away. Shooting with a 16mm ultra-wide, the hyperfocal principle says that as long as you focus beyond 5 meters, everything in the frame is sharp. To be safe, I usually focus at around 7-8 meters."},{"t":"h","x":"景深合成","xe":"Focus Stacking"},{"t":"p","x":"大光圈拍摄的弱光环境下，如果前景很近，单张拍摄很难满足景深的需求，可以用景深合成技术来解决这个问题。分别手动对焦星空和前景拍摄两张照片，一张星空清晰前景模糊，另一张前景清晰星空模糊。后期各取两张图片中清晰的部分在Photoshop中加蒙版合成。","b":false,"xe":"In low light with a wide aperture, if the foreground is very close, a single frame can't deliver enough depth of field — focus stacking solves this. Manually focus on the sky for one shot and on the foreground for another: one with sharp sky and blurry foreground, the other with sharp foreground and blurry sky. In post, take the sharp part of each and composite them with masks in Photoshop."},{"t":"p","x":"上篇知识点总结","b":false,"xe":"Part 1 Summary"},{"t":"p","x":"1. 银河季大致为每年3月-10月，其中4月-7月为最适宜拍摄月份","b":false,"xe":"1. Milky Way season runs roughly March to October each year, with April to July the best months"},{"t":"p","x":"2. 挑选无云或少云天气，远离光污染地区拍摄，并尽量避开月光干扰","b":false,"xe":"2. Choose cloudless or nearly cloudless weather, shoot far from light pollution, and avoid moonlight interference where possible"},{"t":"p","x":"3. 器材：高感全画幅相机+大光圈广角镜头+三脚架","b":false,"xe":"3. Gear: a full-frame camera with good high ISO + a fast wide-angle lens + a tripod"},{"t":"h","x":"4. 参数：ISO3200-6400，F2.8 - F4, 25-30秒","xe":"4. Settings: ISO 3200-6400, f/2.8-f/4, 25-30 seconds"},{"t":"p","x":"5. 构图时注意星空和地景的结合，选取适当方法给地景补光","b":false,"xe":"5. When composing, combine the sky with the foreground and choose an appropriate way to light the foreground"},{"t":"p","x":"下篇将于下周二转载，介绍星空后期的各种降噪方法和适用情况，以及星轨的拍摄技法，敬请期待。","b":true,"xe":"Part 2 will be reposted next Tuesday, covering the various night-sky noise-reduction methods and when to use them, plus star-trail technique. Stay tuned."},{"t":"p","x":"本文知识点，部分节选于笔者朱静姝 (Jingshu Zhu) 的新书《追光之路》，预计今年五月出版。","b":false,"xe":"Parts of this article's content are excerpted from the author Jingshu Zhu's (朱静姝) new book \"Chasing the Light\" (《追光之路》), expected to be published this May."},{"t":"img","f":"img-20","w":627,"h":800}],"titleEn":"The Most Detailed Astrophotography Beginner's Guide (Part 1)"}