Trying to create a nice underwater scene. 1. I have created a "Quadratic Spotlight" and have applied a "Caustics Gel" to it. I placed it directly above the water. Why are the caustics not showing up on the sphere? 2. Is is true that ecosystems cannot be created on a ground plane? I tried but it did not work. 3. I created a plane and gave it a sand texture. I the made it into an ecosystem and selected 3 underwater plants. I then selected "populate" and it said I had about 1400 instances, but the plants are not there when I render the scene. What am I missing? I will post my settings. 4. I am using the "tropical water" but the color is very green. If I want to select a new "ColorMap" why can't I just select a color from a color wheel etc. It seems that there ar onle the solid colors to choose from. How do I make a new one? 5. In the horizon where the floor meets the water there's a black line. How do I get rid of this? Sorry for all he questions.

Here's the settings for the quadratic light and the caustics gel.

Here's a side view showing you where I placed everything.

Ecosystem settings (General Tab)

Ecosystem settings (Density Tab)

Ecosystem settings (Scaling Tab)

1. Your light and/or your atmosphere has to be volumetric in order to show light gels 2. Ecosystems do work on planes. I'm not sure why the ecoobjects aren't appearing. It looks like 1453 instances were created. But i see that little exclamation point in your sand underlying material. I think this means the material has to be refreshed somehow but I don't remember how to do it.

1.A probability is that the sun light is too strong and drowns the spot effect.
In order to tune the caustics, you could make the sun color black, then tune the strength of the spot on the sphere.
Then, it is almost certain you'll want to resize the scale of the gel: the pattern could be much too big with the mapping/scale you have in the scene to be visible.

1. You cannot populate Infinite planes. (because an infinite number cannot be computed by definition.)

3.I believe it comes from the variable scaling being checked and the function is a constant -1 (it appears black on you screenshot) which means the instances are there, but microscopic/invisible.

4.Color. You can change any color you like. Loading or editing a color map. just add keypoint colors in the map where you need them.

1. The black line ? I don't understand. because usually (and in your scene too) it looks more like a white strip.
   Which comes from water 'murkyness'. the water plane being infinite, any amount of murkyness will end in opacity with the distance. You most certainly changed the default dark blue to white, hence the white strip in the distance.
   remedy: create some kind of terrain to use as background.

This is mostly guesswork, hope it can help anyway :)

Well thank you all for your help. This is looking a lot better to me. 1. Do the size of the caustics look real to you? Does the overall water, color, caustics look real? 2. There's one thing that puzzles me though. The Quadratic spot light has the caustics gel applied to it. The sunlight does not. The Quadratic Spot is volumetric and the sunlight is not. I wanted to lower the intensity of the sun, but I could not find a simple way to do this. I finally had to change the color of the sun to a darker color to lower it's intensity, but this seems odd. Is there no way to keep the sun white in color and lower it's intensity or brightness to 50% for example?

The only way to lower the brightness of Directional Lights (e.g. the sun) is to change the color. This is because directional lights are infinite. Changing the color to a greyscale value of 128 (in any color) will cut its power by half. Your caustics look great to me.

Changing the sun color is one way to change sunlight intensity. You can also change the "Light Intensity" slider in the "Light" tab of the "Atmosphere Editor". Be sure the checkbox is set to "Sun only", or it will affect all light sources.

When changing sunlight color, to stay "white", just keep sunlight colors pure neutral (i.e. equal values of Red, Green and Blue). Pure white = full intensity, gray = some intensity, pure black = sun off.

I think your caustics look good - could be a bit brighter (lower sun intensity, as you already said). Maybe the water looks too clear? Hard to say without background objects.

_ jc...'Art Head Start' e-book
.......'Art Head Start.com site Digital Art skills. Free lighting chapter, tutes, Vue models, tex pix.

In the atmosphere editor and in the light tab and in the global lighting adjustment section, the light intensity should help you adjust the suns brightness. If the settings below it is set to "only sunlight" it will just effect the sun. :)

As for the caustics, hard to judge them till the final picture is basically complete. What may look too big now, may not when the ground is loaded with items. Adjusts its size at the end of your project. Or atleast that is what I do. I always adjust the lighting last. :)

Thanks. I will try and post a more complete picture in a day or two.

Attached Link: http://www.lysator.liu.se/~kand/caustics/

I think your caustics don't lok so good, but it's the gel's fault, not yours. If you used the Caustics generator, which is so easy to learn, then they would look a lot more real, imho. Render your caustics in grey shades, apply the render as a light gel, reduce the size of the image map to about 0.4x0.4 and see for yourself. About the white line, it's the fog, try reducing it, or lower it, and if it doesn't work, you will have to place rocks or terrains to hide it. To change the water colour, you can eitheir use the overall colour correction, and you get the colour picker, or right click the gradient to edit it, and in the newly opened tab, click the key colour, and you get the colur picker.

Hi LMcLean

I used a velocity animated caustics .MAT applied to a plane between the water and sun in an animation I made with V5E for my first (underwater) animation.

A (highly compressed) version of the clip is on the C3D Animation Gallery so you can see if it's what you want to achieve, and i'm attaching the Caustic .MAT file should it help you.

Kind regards

P.S. Also thought to mention that EcoSystems will not populate below another object unless you click the tiny plant icon in the top right material preview that "Ignores object(s) when populating EcoSystems"

P.P.S. Rename the .TXT attachment to .MAT to work

(And here's a frame from the animation with showing the caustics and volumetric spotlight)