The Blog

About Me

Marius Oberholster Hey! I'm having an incredible learning experience, not only learning how Blender works (yes, still learning), but also about Open-Source and the incredible software available. Stick around!

Underwater compositing - Mist

Posted by Marius Oberholster on Wednesday, January 28, 2015 Under: Quick Blog Tutorial
Hey all!

Been a while since the last post, but this one is something I've learned a little bit on, so I hope this helps you tons! :D

Something that can easily be missed when it comes to underwater compositing is mist or a cloudiness. This comes from the way light bounces in the water, as well as other particles in the waters. Just think of a misty day. You can only see so far. Depending on the kind of water you are in, you will have varying decrees of clarity.

BUT! This is not a white mist. There are some places where the water gets a white, milky look to it, but we're not talking about that, we're talking about sea water and some river's water in general. This mist is something that has two components:
1) It colors things blue in the distance
2) It diffuses clarity into a blue-green cloud

So, let's see another example of compositing done for underwater shall we:

Now that is one of my personal favorites! :D

This is what it looked like before compositing:

So, how do we set up our scene, so that, we can get the right effect?

Simple, you just need your depth pass and you need to stabalize it (so that it does not jitter with the amount of objects the camera can see in it's current view, because that changes it).
This you can do through a Color> Mix node. For a single image, like the above, you can use Vector > Normalize.
Your Z-pass or depth pass, will go into the mix node's first color input and the second one you will make black. Then you simply adjust it until you are satisfied that you can see what you want to see (usually a factor slightly above 0.98). It can look something like this:

(Notice that the edges are jagged - use a Filter > Blur node to soften it a tad)

Now, if this is waaay to much mist for you, you can always adjust it using a Converter > ColorRamp node to either lessen, shift or increase it.
This will become your factor (fac) in the next Color > Mix node.

You will do this twice, because we need one that is our coloration and one that is our mist. Coloration will get closer to the camera than the mist will, so you may have to use a ColorRamp node at least once in this compositing process.

To color your image, you can do one of two things - Cverlay with a color, or Color with a color using a Color > Mix node.
Your first color input is your base image and your second color input is your 'what will be mixed' image.
For example - let's say I have a beautiful mountain scene and I want to add some light to it, but I don't have an image yet, so I opt for just making it brighter using an all-white look.
To do that, I would have to input my mountain image in the first input and the second input will be the white, so that the white can affect the mountain and not the mountain the white.
The second input is applied to the first according the factor value or input.
   Back on point - we input our underwater scene into the first color input and our water color will go into the second (note, factor will be 1 on this and the BlendType should be either color or overlay - I recommend color - feel free to experiment though. Who knows, you may get a better result you can then teach others ;)

Now! We have the following:
1) Our mist (the reduced depth)
2) Our coloration distance (the initial depth we settled on for the mist)
3) Our raw scene rendered
4) Our raw scene rendered colored blue-green for the water

Using our coloration distance as a factor, create your colorized scene (ie raw scene that fades to a blue version in the distance) using a Color > Mix node.

Using our mist, we take our Colorized scene and place it into another Color > Mix node, into the first color input. The second will be, again, our water color, but this time it will create that cloudy misty look.

And if you did only this, you would have this effect:

Unfortunately, we don't have much color in this scene, but I've noticed on documentaries, unless there is a lot of fish or coral, you're just not going to get much other than browns, greens and blues and possibly some reds.

Anyhow, that is it for this tutorial. I hope it helped you immensely and that with this and the previous post, that you're one step closer to that underwater look you may be after! :D

A little tech-ish info on the image:
- Render engine: Blender Render (does not affect compositing - same applies for Cycles)
- Size: 50% HD
- Landscape generated with Landscape generator (built-in)
- Water surface - procedural texture (Clouds)

Have a great one!!

Thank YOU!!!!!!!!!!

In : Quick Blog Tutorial 

Tags: jesus  god  holy spirit  underwater  compositing  blender  mist  cloudy  blender render  colorramp  normalize node 

"For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book:
And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and from the things which are written in this book.
He which testifieth these things saith, Surely I come quickly. Amen. Even so, come, Lord Jesus.
The grace of our Lord Jesus Christ be with you all. Amen."
Revelation 22:18-21

"Add thou not unto his words, lest he reprove thee, and thou be found a liar."
Proverbs 30:6

King James Version, Public Domain

Ultimate Glory

I give glory to, acknowledge and remember God for this website. He enabled me to do all this and this website belongs to Him. Thank You!


Make a free website with Yola