Cineversity

Hello:

I’m doing an outdoor scene of a cabin with crops and trees behind it.  I want to add aerial perspective.  Both the native Environment object and CS Fog can create fog to mimic this effect.  The problem is, the effect starts right at the camera, so I’m seeing a shift in color on my cabin which is only 15 feet away.  I don’t want the fog to start until it’s 50 meters away or so.

In Lightwave you had the ability to have the fog start a specified difference away from the camera and have it be at 100% at a farther specified difference.

Do I have to use the camera’s depth-of-field settings to fake this?  That would be a bummer in case one wanted shallow depth of field on an object with aerial perspective stretching into the distance.

Thanks.

Shawn

Hi Shawn,

Have a look to the attached file. You can use the fog channel perhaps to get what you need. IF you need more adjustment, perhaps you place two objects on top of each other.

LightWave, nice that you can relate to it, but mentioning it won’t change the options here. I have stopped using it after v6.5, so I can’t even follow.  If you like to dive into an application, leave application specific options from another one behind you, it will limit yourself more than it helps you. I have explored/learned in the past decades quite some apps—I own over two hundred licenses (many EOLs though), and that is the base of my experience. Sticking in another app makes “you” blind for the individual and alternative options in the one you like to learn.

What I take from the LW “quotes”, that you are experienced and that you don’t need to know much details to keep going. Let me know if I’m wrong, I adjust my comments then in future :o)
Having said that, I hope the file will help more than words.

All the best

Sassi

P.S.: Perhaps this is even simpler. I used just a plane on the camera. There is a Compositing Tag on that plane, to prevent that it cast shadows etc. If you unfold the “scene” you see an object with a transparent object. If you un-check the “Seen by Transparency” in the Compositing Tag, and the sphere is active, the Fog is gone where the Sphere is in the camera view. (Just to illustrate some options and perhaps limitations.)
I never have used it in production, I just have put this idea together, please test it if it works inside of your scene.

I guess I never thought to use a fog material in an object.  I’ve seen it 100’s of times but never noticed it.

So this does work to make the fog start farther from my camera.  Unfortunately it’s also totally obscuring my Sky Object.  I haven’t found any combination of tags that will make the sky object visible.  I’m thinking I’m going to have to use some depth pass and add the fog in compositing.

Also, I’m not bringing up Lightwave just to gripe.  I’m just relating some functionality it has in the hopes that someone here with more expertise than I have in C4D knows of comparable functionality.  In my recent post about auto-keyframing I said up front that I’m really happy with many of the features C4d offers.  I’m able to do projects I couldn’t begin to tackle in LW.  But that doesn’t mean that Lightwave doesn’t do some things better.  Not just different, but better.  And as far as I can tell their implementation of fog offers the artist more control.

Cheers.

Shawn

Hi Shawn,

Fog (material channel) is very simple in its use. Especially since you have an object to deal with.

Depth path would require of course then to render out much higher resolution. A depth pass is not anti aliased, as it is an information pass pass. yes it is based here on gray values. Rendering it with AA might result in artifacts. many people do not realize that and end up with weird edge treatment. However, it is project and quality dependent—target wise of course. There is of course a lot possible with the depth pass, and if render out nicely, you might get a better result, as fog, environment or any of these options normally affect only the RGB values of each pixel. Areial perspective is certainly not that simple, if you go for something more adequate.

Going from one application to another had for me always a more or less claustrophobic feeling, as I always compared. In one app a pro and in the new one a starter. Nothing that I call fun. But having done it often enough, I know the reasons and worked myself to an position of accepting the limitation as a starter, it works much faster than. But you go your way of course. However:
I stick with it, LW and C4D are two different packages, and as long as you search for similar things—your questions will limit the answer! But go ahead if you like as before, it is your question.  Lightwave has certainly other options, but in the moment you have to explain first what it can do to anyone here, after that is communicated in detail (other wise it makes no sense) you finally start then to create your question. At a point where most people have perhaps already skipped your question. I leave it alone, do what makes you happy.

If you use the Environment (I thought you don’t) then check the “Affect Background”, then you can dial in the “Sfumato” or Arial Perspective to match the scene. You have (obviously?) a very small scene, so the Environment becomes affected based on a high setting, to affect the middle ground properly. Just an assumption. If i set the picture viewer to “A/B Difference” small values in my example scene here doesn’t show such effect.

A light source with no Diffuse/Specular, but set to Volumetric, could help here. Lights have the option to Clip their effect (Near/Far) in the Detail tab. Setting up a spot light and make it a child to the camera (same position) might produce what you like for the foreground. But yes it is between camera and sky object and will so affect of course the sky.

The simplest way, and again—only affecting the RGB values, not producing the real effect—is to place an gradient in each material to translate the saturation and “brightness” of the colors. In C4D you have the option to set a 3D gradient up, and set via XPresso the center of all Gradients to the center of e.g., the camera. Now you set up when and how (distance wise) each material is affected, or not at all. You avoid long calculation times, depth pass and rendering in passes to compose it later. See attached file. The XPResso is done with Set Driver/Set Driven Absolute. Gradient Space is set to “World”. The colors are set for illustration purposes.

All the best

Sassi