标题: (photoshop)'Clouds from Above '－－制作俯视的云层 [打印本页] 作者: 火柴盒 时间: 2008-4-22 07:31 标题: (photoshop)'Clouds from Above '－－制作俯视的云层
'Clouds from Above '－－制作俯视的云层 'Clouds from Above '
by Marek Hlavaty
原文链接：http://www.3dtotal.com/team/Tutorials_3/cloud_from_above/clouds_from_above01.asp
Hi, my name is Marek. I work as an illustrator and background artist. Painting sky scenery and dramatic clouds is an important part of my job. I wrote this tutorial to share my skills in this particular area of painting. The creation of nice and realistic clouds is actually not too demanding on time or technology. In spite of this I had been painting clouds in a particular method, which had not been generating satisfying results for many years. The main reason for this was because I wanted to paint everything with one brush, soft or hard. I really didn’t like clouds painted in this way. Recently I decided to change the way I do things. It resulted in finding out a method which allows me to paint very realistic sky scenery. First of all I’ll explain the basic principle of painting clouds. I use two types of brushes. First one is soft with smooth transition, the second with harder edge. It’s because when you take a look at the cloud, you’ll find out that its kind of a strange blend of smooth transitions in one hand and sharp contrasts with hard and bright outlines on the other. In the next few pictures I’ll show you how to perfect the illusion of marvellous fluffy cumulus clouds.
This image presents the cloud painted with soft brush. It reminds me the cloud in general way, but on the first view you can feel, that its not quite there yet.
（下面这张云的图片是用软笔刷绘制的。它告诉了我绘制云层大体的方式，但是第一眼看去，你感觉不到云在那里。）
I have switched from soft brush to harder and adumbrated the edges of cloud lightened up by sun. But there are still hard outlines on the shadowed side of cloud. We can solve this problem by switching to soft brush and creating smooth transitions.
(我选择了从软到硬的笔刷来描绘云层被太阳照亮的边缘。但是在云层的阴影部分仍然有硬的轮廓线。我们可以通过选择软的笔刷创建平滑的过渡来解决这个问题。）
Now we need to get rid of this big white stuff in the middle of the cloud. It looks little bit useless, and besides that, its situated in the area which needs to be slightly shadowed. We’ll also make the dark parts of the clouds on the left stronger.
（现在我们需要除去云彩塞在中间的那个大白团。它看上去没什么用处，此外，它处的位置需要一些轻微的阴影。我们还需要将左侧云彩的暗部加深。）
These kind of clouds can be created when the Observer, Cloud and the Sun are in the same position, as you can see in the images below.
（当观察者，云彩和太阳处在如图所示的位置时，你可以创建这样类型的云。）
If we want to select the different lighting (for example the same as on the above image, where the cloud is almost between the sun and the observer), we need to proceed in the same way, as what has been shown on the image below. The bigger part of the same cloud, which was the subject of our effort, will stay in shadow on our side of view. So we will paint over it by using dark colours and only let the edges shine, which are lightened up from the sunny side.
（如果你想选择不同光线（比如跟上面第二张图一样，云层处在太阳和观察者之间），我们需要用同样的方法来处理，如下图所示。更大的一片云层，从我们的视角来看是处于阴影中的。所以我们将用深色来绘制它，仅仅在边缘的地方呈现出光线，它们被太阳所照亮。）
We then add some details and lighten parts of the cloud, which are probably not sufficiently thick enough to create the deepest shadow. And that’s how you paint basic clouds.
（然后我们给它添加更多的细节，并加亮部分不太厚的云彩，因为它们不足以产生如此深的阴影。这就是绘制基本云层的方法。）
Creation of these clouds takes me about 10 minutes and I’ve used just two brushes. One plain soft brush with Scattering function, and the second one – harder brush, which reminds me of smoke or the little cloud. You just need to set up the plain soft round brush as a masking brush in the Dual brush menu. It’s fully sufficient not to create a repetitive pattern when using the brush. When you learned these techniques, you can try to paint more challenging sceneries.
（创建这些云层花了我大约10分钟的时间，我仅仅使用了两种笔刷。一种是有散布功能的柔软笔刷，另一种是更硬一点的笔刷，它使我想起烟或是小块的云。你仅仅需要在双重笔刷菜单中设置柔软的圆形笔刷作为遮罩笔刷。当使用这些笔刷时，它完全不会创建一个重复的图像。当你学会了这些技术之后，你可以试着绘制更有挑战性的场景。）
点击图片可以查看大图
First of all we need references. I have found several photos of clouds, taken from high altitude (probably from an aeroplane window) on the Internet. Everyone who has flown sometime had surely seen a view like these. I’ve picked certain clouds which are lightened by bright white light, approximately in the afternoon. This are the proper conditions I need to create my picture.
（首先，我们需要一些参考资料。我已经在网上找到了许多从高空采集的云层的照片（可是时从飞机的窗口拍摄的）。坐过飞机的人有时可能会看到这样的景色。我挑选了几张大概是下午被阳光照的雪白的云。）
I have laid out a basic structure and some shapes. On the left side of the picture I’d like to have a big bunch of clouds, in the middle and on the right will be the clouds will be a little more scattered, extending towards the distant horizon.
（我铺设了基本的结构和一些形态。图片的左侧我希望有一朵很大的云彩，在中间和右侧将是一些细小的，很多零散分布的云，它们一直延伸到地平线。）
I adjusted the contrast and saturation of the picture. Then I have created the basic effect of Cumulous formations raising up from the normal height of the clouds. Compact clouds are used to create towers and hills of clouds rising up by airflows. You need to realize that all of the clouds create shadows behind and underneath them, so you’ll need to sketch that in.
（我调整了图片的对比度和饱和度，然后我通过提升云的正常高度，创建了Cumulous（一种在平缓的云层上生成圆球云团的云彩构造）构造的基本效果。紧密的云彩被用来创建被气流提升起来的云塔和斜坡。你需要意识到所有的云的阴影都在它们下面，所以你需要将它描绘上去。）
I have added more contrast and saturation again. The basic mass of clouds starts to look like what I had in mind.
（我增加了更多的对比度和饱和度。云层的规模跟我脑子里所想的开始接近了。）
作者: 火柴盒 时间: 2008-4-22 07:39
It’s time to give the scenery depth and space feeling. I have concentrated on the clouds in the distance and added some breaches in the basic level of clouds. Airflows create not just towers and hills, but also some breaches and abysses. I have painted them by using a rich blue colour, so that it could look like there’s an ocean under the clouds. I have lowered the opacity of the layer with details in the back. It’s because I wanted to simulate this misty atmospheric effect (haze), which usually appears looking over vast distances.
（是时候给场景添加一些纵深和空间感了。我将此集中在云的距离上，并在基础的云层上添加了一些缺口。气流不仅仅创造了云塔和斜坡，同样导致了缺口。我用饱和的蓝色绘制了它们，这样它们看起来在云层下面有一片海。我降低了后部细节层的透明度。因为我希望将此解释为大气效果，这在观察极远距离的空间时会出现。）
I have added some more detail to the clouds in the front, without this they would look like they would be closer- and I did not want this. I want the observer to have the feeling that he or she is very high above the huge mass of clouds.
（我给前景的云层添加了一些细节，否则他们看起来会太接近了，我不希望这样。我希望观众有这样的感觉：他或是她正站在巨大的云彩上面。）
To polish off my work I have tuned up the saturation of the cloud-shadows in the front and gave them slight tone of yellow-green colour. Thanks to that, they do not look so monochromatic.
（为了润色我的作品，我提高了前景云彩阴影的饱和度，并给他们一点黄绿的色调。得益于此，他们看起来不才不至于那么单调。）
When I showed the finished picture to my girlfriend, she was able to tell me a very unbiased opinion. When you work on something long enough, you sometimes become blind to some of the errors that may lie within it. Having a person who hasn’t been staring at the work as long as I have and telling me that it looks good must mean that my work on the background is definitely finished. The clouds look really spectacular and the viewer has the feeling of flight above the vast space. That’s exactly what I was aiming for in this picture, and it only took me about 2 - 3 hours.
（当我将这幅完成的图片秀给我女友看时，它给了我一些非常客观的评价。当你做某件事时间太长，你有时会对一些错误变得麻木。有这样一个人，它从未看过我的工作直到我完成，然后它告诉我那看起来不错，这意味着我背后的工作确实是结束了。云层看上去真的很壮观，观察者的确有从飞机撩望天空的感觉。这就是我在这幅图像里所要达到的目标，它花了我2－3个小时。）
来源：译文3D网
