<p>The File Properties provides a number options for the appearance of the scene including
background color, image and fog properties..</p>
<h4><strong>Scene</strong></h4>
<blockquote>
<p><strong>Background</strong></p>
<blockquote>
<p>An image may be selected that will be rendered as the background to your scene.</p>
<p>You may disable the background image from being rendered by de-selecting <img src="../images/Button-Image.gif" alt="Button-Image.gif (171 bytes)" WIDTH="24" HEIGHT="22"> on the <a href="misctoolbarmain.htm">Main Toolbar</a>.</p>
<p><strong>Color</strong></p>
<p>You may alternatively select a background color to be rendered as the background to
your scene.</p>
</blockquote>
<p><strong>Raytracing </strong>(Available with <a href="registration.htm#pro">3D Canvas
Pro</a>)</p>
<blockquote>
<p><strong>Radiosity Level</strong> (Available with <a href="registration.htm#pro">3D
Canvas Pro</a> when using raytraced rendering)<br>
<br>
Radiosity lighting produces much more life-like lighting than standard raytracing
provides.<br>
<br>
The quality of radiosity light can be adjusted. A value of zero means do not render
radiosity lighting. </p>
</blockquote>
<p><strong>Atmosphere</strong></p>
<blockquote>
<p>You may disable fog (atmosphere) from being rendered by de-selecting <img src="../images/Button-Fog.gif" alt="Button-Fog.gif (158 bytes)" WIDTH="24" HEIGHT="22"> on the <a href="misctoolbarmain.htm">Main Toolbar</a>.</p>
<p><strong>Mode</strong></p>
<p>You may select the mode in which fog will be rendered. The general options are Linear,
Exponential and Exponential Squared. If you are a <a href="registration.htm#pro">3D
Canvas Pro</a> user and are rendering with POVRay you can also choose to disable standard
fog and only render atmospheric effects created by particles (See below).</p>
<p><strong>Color</strong></p>
<p>The color of the fog may be selected by clicking on the current color.</p>
<p><a name="raytracingparticles"></a><strong>Raytracing Particles</strong> (Available with
<a href="registration.htm#pro">3D Canvas Pro</a> when using raytraced rendering)</p>
<blockquote>
<p>This simulates the effect of light reflecting off of particles in the air. It is useful
for producing "visible light" such as Spotlights in fog. </p>
<p>Note that there are a few tricks to getting a good effect with this in POVRay:</p>
<ol>
<li>To enable "visible light" it is necessary to enable <strong>Render Atmosphere</strong>
on the primary toolbar.</li>
<li>You will need at least one spotlight in your scene or you will not see any "visible
light".</li>
<li>"Visible light" is only visible if there is something behind the "visible
light". This is easy for any scene that takes place in the interior of a room. But if
you want to have "visible light" in "space" you will need to create a
giant sphere and place your spotlight and camera inside it. This appears to be a bug in
the current version of POVRay. It may be repaired in the future.</li>
<li>You may need to add additional lighting to your scene since "atmosphere" acts
like fog reducing the amount of light in a scene. </li>
<li>Making the Atmosphere's <strong>Linear: Max</strong>. (see below) large helps make the
scene brighter.</li>
<li>All point lights and parallel point lights in your scene must be set to <strong>NOT</strong>
cast a shadow. You can do this by right clicking on the lights and de-selecting <strong>Cast
Shadow.</strong> This appears to be a bug in the current version of POVRay. It may be
