= How to |> convert an object into smoke =

# Create an object on a grid. 

    In this example we will use teapot object from the [Icon:sop/platonic][Platonic Solid|/shelf/platonic] tool on the shelf. The grid is necessary so you have something to cast shadows on.
    
    [Image:/images/howto/convertobjecttosmoke1.png]

# [Set up a light and a camera.|/shelf/lightsandcameras]

# Dive into the teapot object and append an [Icon:SOP/isooffset][Iso Offset|Node:sop/isooffset] node.

# Change the __Output Type__ parameter to __Fog Volume__ and increase the __Uniform Sampling__.

    In this example we will increase the __Uniform Sampling__ to `50`. 
    
    [Image:/images/howto/convertobjecttosmoke2.png]
    
# Drag a volume material from the [Material Palette|/ref/panes/materialpalette] onto the teapot. In this example we will use [Billowy Smoke|/gallery/shop/material/billowy_smoke].

    NOTE:
        Volume primitives need to have volume materials applied to them before you render. There are several volume materials on the [Material Palette|/ref/panes/materialpalette] such as:[Basic Flame|/gallery/shop/material/basic_flame], [Basic Liquid|/gallery/shop/material/basic_liquid], [Basic Smoke|/gallery/shop/material/basic_smoke], [Billowy Smoke|/gallery/shop/material/billowy_smoke], [Constant Smoke|/gallery/shop/material/constant_smoke], [Fluid Fire|/gallery/shop/material/fluid_fire], [Volume Cloud|/gallery/shop/material/volume_cloud], and [Wispy Smoke|/gallery/shop/material/wispy_smoke].
        
# You can improve the quality by modifying the material's parameters. For example, you can lower the __Frequency__ to 1.

    [Image:/images/howto/convertobjecttosmoke_render.png]
    
# To create shadows, navigate to the __Shadows__ tab on your light object, and change the __Shadow Type__ to __Depth Map Shadows__.

    [Image:/images/howto/convertobjecttosmoke_render2.png]
    
== Improving the render ==

To improve the look of your render, try modifying the following parameters.

* Increase the __Pixel Samples__ on the __Shadows__ tab of your light object and the __Uniform Sampling Divs__ on the [Iso Offset|Node:sop/isooffset] node.

    In this example we increased the __Pixel Samples__ to 2 and the __Uniform Sampling Divs__ to 75.
    
    [Image:/images/howto/convertobjecttosmoke_render3.png]

* Click ((MMB)) the [Iso Offset|Node:sop/isooffset] node and divide the largest __Size__ by the largest __Volume Resolution__. This should give you the proper value to use for the __Volume Step Size__ parameter on the __Sampling__ tab of the [mantra output node|Node:out/ifd].

    [Image:/images/howto/convertobjecttosmoke_mmb.png]
    
    In this example the value for the __Volume Step Size__ should be `0.2797373`, which is the value you get when you divide `2.09803` by `75`.

* If you are using motion blur, you might see black artifacts are around the edge of your object. Make sure the __Depth Map Motion Blur__ checkbox is turned off on the __Shadows__ tab of your light.