The amount of RAM needed depends on several factors: - Resolution: The bigger the render the more render calculations Maxwell has to keep in RAM.
- Multilight: Each separate light sliders needs to be stored in RAM so the more separate sliders you have, the more RAM is needed. To minimize the RAM usage you can apply the same emitter material to several geometry objects that are ment to be emitters in which case they will all use the same slider - saving RAM. Color ML will need more RAM than regular ML because each color channel per light also needs to be stored in RAM.
- Size of textures: Every texture used in the scene, including IBL maps, need to be stored in RAM.
- Geometry: Although the amount of triangles plays a smaller part in the RAM usage compared to the points above, it still affects the RAM needed but in most scenes this will be of minor importance.
- Pretesselated displacement: This type of displacement subdivides the geometry before rendering (unlike On-the-Fly displacement), which renders fast but needs to hold the extra geometry in RAM. The higher the subdivision setting in the displacement material, the more RAM is needed.
- Extensions: Hair and particles need more RAM - the more segments the hair has, or the more particles you have. Although these extensions are very efficient, they will use up RAM if used in the scene.
- Extra render channels: The extra channels you can specify in the render options (Alpha, MatID, ObjectID, Normals etc) will need extra RAM to render. The amount they need depends also on the resolution of the main render.
Taking into account all these factors it is impossible to say how much RAM you will need for a certain render. It is best to test a render on your machine and check the RAM usage during the render. On Windows 32 bit computers, each application can use a maximum of 1.6GB of RAM (or 3GB by changing the boot.ini file - see the next FAQ). This will be limiting if you want to do higher resolution renders. It is strongly suggested to use a 64 bit system which can use up to 128GB of RAM. |