Panorama 全景相

全景相就是那些把180度或更闊的畫面展開的相片，當然有專用相機可以製作，這些相機亦是很貴的，非一般業餘玩家可以享用，另外也會有一些相機，甚至乎是一些小DC也有在相機內設置了Panorama功能，可以不假外求便能拍出全景相，不過一般人只要用普通相機順序影多張相片後再用軟件駁起來，也可以做到全景相。其實只要留心一下拍攝的細節，也會易於成功。	Panorama is a kind of photo that puts 180 degrees or more of a view onto one photo.  Some delicated but expensive cameras on the market are good for this use but not unluckily they are not readily available to us.  Some cameras, or even small DCs, have a panorama mode that helps the users in making panorama photos within their system.  However, we can still make panorama photos by common cameras if we can observe some key points when taking a series of pictures of the view in order.  These pictures can be stitched into one pictures that makes the panorama.
上面的一張全景相，其實是用了下面六張普通相片駁接而成的，它們是我站在家前的露台上拍下來的。	The above panorama photo is stitched by the following 6 photos that I took from my home.
拍攝的時候，我站在一點上沒有移動過，只是轉動身體面向不同的角度把差不多150度的景物拍了下來，就是這六張相片了。之後我用我的Canon相機附送的軟件PhotoStitch把它們接駁起來。其實軟件可以選用很多別的，例如用Photoshop的話，它們也有駁相的功能，用來也大致一樣。也可以下載一些免費的駁相軟件，不過我沒有用過，不便介紹。 下面是我用PhotoStitch的過程	The above photos are taken by panning my camera while stands on a fixed point.  When these photos are ready, I put them into a free software PhotoStitch that I got when I purchased my canon camera and it stitches the picture for me without much work to do.  Of course, there are other softwares like photoshop that can do the same job.  There are also free software you can download to do so but as I have not experience on them I cannot give any suggestion. The following pictures show the steps I needed to make the above panorama from the raw phots.
fig 1 : put all pictures into the software fig 1 : 把所有圖片載入軟件內
fig 2 : arrange them in correct order fig 2 : 排列好照片的正確次序
fig 3 : set the panorama setting for the final picture fig 3 : 設定好全景相的參數
fig 4 : start merging the pictures fig 4 : 讓軟件接駁好相片
fig 5 : before saving the final picture, we can select the crop of the picture fig 5 : 選好裁相範圍後存檔
不過，要做到好的全景相，拍攝個別照片時有一些地方是要留意的： 每張相片要保留與下一張相片重叠的部份，這是不言自諭的了。 拍攝時相機若可以設定為固定光圈及快門的話請用M模式固定，因為讓相機自動測光的話，不同的部份會有不同的效果，全景相便不會統一起來。  對焦亦要選用手動模式，如果想要有最深的景深，可以用泛焦的做法。 相機最好放在調好水平的三腳架上拍攝，這樣的話相片不會一張跟另一張的高低不同而影響到最後裁相時只有很窄的可用範圍。 若有焦距可以選擇的話，盡量用標準或長鏡的範圍，因為廣角鏡必定有透視的變形，影響到相片接駁後不自然。	To me, I believe there are two solutions. Every single picture should overlap with the next picture.  So you need to take your pictures with about 1/4 in common with the next picture. To make the final stitched picture in one same tone, you need to take all the individual picture with the same shutter speed and aperture.  Thus using M mode instead of any automatic mode like A, S or P is the key point.  Focusing should be set into manual mode.  Use hypo-focus if you need to obtain the greatest dof. Put your camera on a leveled tripod so that all pictures are taken at the same height and the cropping of the final picture will give the greatest height when pictures are aligned.  Choose a standard or tele lens to use.  If wide angle lenses are used, the side of the picture will be stretched and makes the final stitched picture not looking natural.
上面可以見到另一張全景相，都是在同一地點拍的，只是拍的時候用的是廣角鏡，從左面的樹變細便可以明白了，你會發覺遠方的海岸線並不平直，這是廣角變形所做成的。	I have put another panorama of the same view together with the one we have seen before above.  This one is taken with a wide angle lens and you can see the tree at the left looks smaller due to the effect of the wide angle lens.  From the sea level, which is not straight, you can tell the effect of a wide angle lens distortion on our panorama photo.