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The Versatility of Render Clouds
A Demonstration of Render Cloud’s Usefulness
By Ryan Foss

If you’re like me at all, one of the first things you did when you got your hands on Photoshop was experiment with the filters. Filters and fun, they’re easy to use, there are tons for free, and plenty to purchase. The possibilities appear endless. However, there is one filter that comes across as completely worthless, but it isn’t. Clouds, a Photoshop standard filter, along with Difference Clouds, can be used many, many way. Its versatility will amaze you once you realize the possibilities.

I’ve been using Photoshop since version 5.0, as well as doing 3D for just as long and I’ve come to realize the Clouds filter is probably one of those filters I use every day on every project. I make unique and interesting camouflage textures, nebulous starscapes, more organic looking special effects, dirty and rusty textures, and planetary textures or even smoke. And these are just the first few that come to mind. So, I’d like to introduce you to some of the possibilities that are at your disposal using the Clouds and Difference Clouds filters. If you search the net for tutorials on Photoshop using the Render Clouds, you’ll find hundreds of examples. I’ve tried to list some examples that are actually useful, and a little more complicated and interesting than the basic web tutorial.


First, a few basics on the Clouds and Difference Clouds filters. Straight from the Photoshop documentation:

“Clouds Generates a soft cloud pattern using random values that vary between the foreground and the background colors. To generate a more stark cloud pattern, hold down Alt (Windows) or Option (Mac OS) as you choose Filter > Render > Clouds.”

“Difference Clouds Uses randomly generated values that vary between the foreground and back-ground color to produce a cloud pattern. The filter blends the cloud data with the existing pixels in the same way that the Difference mode blends colors. The first time you choose this filter, portions of the image are inverted in a cloud pattern. Applying the filter several times creates rib and vein patterns that resemble a marble texture.”

You might shrug me off as a loon trying to get you to read the Photoshop documentation, but seriously, its worth it in this case. I'll summarize anyway. Clouds takes the colors you've currently have selected and makes a cloud like image. Difference clouds does the same thing, except it applies the clouds over the existing image.

In my Render Clouds tutorials, I usually always start out with a black/white Clouds, then apply a number of Difference Clouds.


The Clouds filters can be seamless (tileable, so that the border is not obvious). Just be sure the image pixel width and height are a power of 2 above 128 pixels (i.e. 1024 x 256, 2048 x 2048, etc).


The larger the image is, the more “cloudy” the image looks. See comparison in the image below.

render cloud resolution comparisson
As the number of pixels in the image grows, the more detail there is when the Clouds filter is used.

With a little forward thinking you can achieve largely different results depending on the size of the image. For example, for finer detail start out with a large image, say 2048x2048, then scale down to your working size. To illlustrate this possibility, I've done an example image using our Cool Psychedelic Ribbons tutorial as an example. The image on the left was made at the target image size 512x512, whereas the image on the right was genereated by starting at 2048x2048.

initial 512x512 image size
initial 2048x2048 image size
Starting with a 512x512 image.
Starting with a 2048x2048 image.

Vein-like Detail

In my Render Clouds tutorials, I usually always start out with a black/white Clouds, then apply a number of Difference Clouds. I do this because as the difference is applied, interesting things start to happen. See the two images below.

difference cloud comparrision
Starting with a black/white clouds, the difference clouds filter is applied a number of times. Vein-like feature details start to emerge.

colored difference clouds comparrision
Starting with Red 255 & Blue 255, this image shows what using color and Difference Clouds can do.

Fixing Seams

Now although the clouds and difference clouds filters can be seamless, applying other filters on cloud images aren't guaranteed to keep their seamless appearance. A example is blurring. Take an ordinary black/white cloud image that is seamless, then apply a Gaussian blur of 10. The seam is compromised because the blur doesn't wrap across the edges. This is true for many of the other filters as well. Now, in this case you could apply a little blur, then Offset (Filter > Other > Offset) but this is laborious and not guaranteed. Plus, it might not work for other filters. So I've come up with an approach I call the Double-Do-It and Crop-it approach to guarantee seem integrity.

The Render Cloud Tutorial Collection.

Don't forget to checkout our entire Tutorials section.

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